Relative risk is the probability of an outcome occurring in an exposed group as compared to the probability of that outcome in an unexposed group. In the scenario given, 50% of the children exposed developed the disease while only 10% of the children who were unexposed developed the disease. The relative risk was therefore 50/10=5. There is no further information about whether the study was controlled, the confidence interval, or the type of study. It therefore cannot be confirmed whether the chemical is causative and if it should be avoided.

Gait variations in children are usually physiologically normal and only become a cause of concern when they persist or are associated with pain or other medical symptoms. Genu varus, also known as knock knees causes an outward rotation of the leg, leading the toes pointing outwards. The condition usually resolves by the age of 18 months. In comparison, in- toeing occurs with genu varus. Metatarsus adductus is also associated with an inward pointing of the toes.

Beckwith-Wiedemann Syndrome (BWS) was first characterized by Patients having abdominal wall defects, macrosomia, macroglossia, and enlarged adrenal glands. Since then, the clinical presentation has expanded to recognize hemihypertrophy/lateralized overgrowth, hyperinsulinism, omphalocele, and organomegaly as classic features of BWS.About 50% of children with BWS have hypoglycaemia and therefore patients with diagnosed BWS should be evaluated for hypoglycaemia. Hypoglycaemia in most BWS new-borns generally resolves within the first few days of life. However, in about 5% of patients that have hyperinsulinism, the severe prolonged hypoglycaemia requires escalated therapy ranging for medication (diazoxide) to partial pancreatectomy.

The progesterone is primarily responsible for preventing pregnancy. The main mechanism of action is the prevention of ovulation| they inhibit follicular development and prevent ovulation. Progestogen negative feedback works at the hypothalamus to decreases the pulse frequency of gonadotropin-releasing hormone. This, in turn, will decrease the secretion of follicle-stimulating hormone (FSH) and decreases the secretion of luteinizing hormone (LH). If the follicle isn’t developing, then there is no increase in the oestradiol levels (the follicle makes oestradiol). The progestogen negative feedback and lack of oestrogen positive feedback on LH secretion stop the mid-cycle LH surge. With no follicle developed and no LH surge to release the follicle, there is the prevention of ovulation. Oestrogen has some effect with inhibiting follicular development because of its negative feedback on the anterior pituitary with slows FSH secretion| it’s just not as prominent as the progesterone’s effect. Another primary mechanism of action is progesterone’s ability to inhibit sperm from penetrating through the cervix and upper genital tract by making the cervical mucous unfriendly. Progesterone induced endometrial atrophy should deter implantation, but there is no proof that this occurs.

Bacterial meningitis (including meningococcal meningitis, Haemophilus influenzae meningitis, and staphylococcal meningitis) is a neurologic emergency that is associated with significant morbidity and mortality. Initiation of empiric antibacterial therapy is therefore essential for better outcomes. The patient appears to be suffering from meningitis caused by Staphylococcus aureus. Methicillin would be the drug of choice . It is bactericidal and unlike streptomycin and chloramphenicol it is not associated with toxicity

Hyposplenism usually occurs after the surgical removal of the spleen or in pathological processes where the splenic tissue is replaced with abnormal tissue. It is often associated with diseases such as sickle cell disease, Coeliac disease, SLE and Dermatitis Herpetiformis. Myxoedema however bears no known association with hyposplenism. Patients with hyposplenism are at risk of fulminant bacterial infection.

Still’s disease is a rare systemic disorder that accounts for 10% of cases of juvenile idiopathic arthritis (JIA). The aetiology is unknown. It affects boys and girls equally up to the age of five years of age, following which, girls are more commonly affected. Clinical features of this disease include:- Fever- Maculopapular rash- Myalgia- Generalised lymphadenopathy- Hepatosplenomegaly- Pericarditis and pleuritis Laboratory investigations reveal raised ESR and CRP. There can also be coexisting neutrophilia and thrombocytosis. Anti-nuclear autoantibodies and rheumatoid factor are usually negative in patients with Still’s disease.On the rare case that they are present, their titres are generally low.

Homonymous hemianopia (HH) is a visual field defect involving either two right or the two left halves of the visual field of both eye. It results from the damage of the visual pathway in its suprachiasmatic part. The causes of HH include stroke, brain tumours, head injuries, neurosurgical procedures, multiple sclerosis and miscellaneous conditions. HH result in a severe visual impairment and affect a variety of cognitive visual functions. Patients with HH frequently have difficulties with reading and scanning scenes in sufficiently rapid fashion to make sense of things as a whole. They stumble, fall or knock objects in their surroundings, since they cannot see them and they are frequent surprised that somebody or something suddenly appeared in their visual field. The prognosis of visual field deficit recovery is highly variable and depends on the cause and severity of brain nd optic pathway injury.

Damage to the left parietal lobe can result in what is called Gerstmann’s Syndrome. It includes right-left confusion, difficulty with writing (agraphia) and difficulty with mathematics (acalculia). It can also produce disorders of language (aphasia) and the inability to perceive objects normally (agnosia).Damage to the right parietal lobe can result in neglecting part of the body or space (contralateral neglect), which can impair many self-care skills such as dressing and washing. Right side damage can also cause difficulty in making things (constructional apraxia), denial of deficits (anosognosia) and drawing ability.Bi-lateral damage (large lesions to both sides) can cause Balint’s Syndrome, a visual attention and motor syndrome. This is characterized by the inability to voluntarily control the gaze (ocular apraxia), inability to integrate components of a visual scene (simultanagnosia), and the inability to accurately reach for an object with visual guidance (optic ataxia)Special deficits (primarily to memory and personality) can occur if there is damage to the area between the parietal and temporal lobes.Left parietal-temporal lesions can affect verbal memory and the ability to recall strings of digits. The right parietal-temporal lobe is concerned with non-verbal memory.Right parietal-temporal lesions can produce significant changes in personality.

Myelomeningocele is the most common type of open neural tube defect and a serious central nervous system disorder associated with significant morbidity. It is also called open spina bifida since the dura, and arachnoid matter herniates through the defect in the vertebral column. The commonest association is the decreased folate levels during early pregnancy. The alpha-fetoprotein levels are raised in the amniotic fluid. CSF leak is a common presentation with associated macrocephaly and hydrocephaly. Prenatal surgical repair is linked to a better prognosis.

While the clinical scenario and the anosmic presentation of the child are highly suggestive of Kallmann’s syndrome, reduced testosterone, FSH and LH levels can confirm the diagnosis.Kallman’s syndrome is a recognised cause of delayed puberty secondary to hypogonadotropic hypogonadism. It is usually inherited as an X-linked recessive trait. Kallman’s syndrome is thought to be caused by a failure of GnRH-secreting neurons to migrate to the hypothalamus.Clinical features of Kallmann’s syndrome include:- Delayed puberty- Hypogonadism, cryptorchidism- Anosmia- Low sex hormone levels – Inappropriately low/normal LH and FSH levels- Some patients can present with associated cleft lip/palate and visual/hearing defects.

Live attenuated vaccines such as the MMR, should be avoided in HIV+ patients.

The most common cause for acute bloody diarrhoea in a 10-year-old child is Campylobacter.Note:Campylobacter is the most common bacterial cause of gastroenteritis in the UK. It typically presents with bloody diarrhoea, fever, abdominal pain and vomiting. The primary source of Campylobacter is uncooked poultry. Treatment is generally supportive unless the child is immunosuppressed or the symptoms are persistent.Other options:- E. coli 0157:H7: It causes acute haemorrhagic diarrhoea, usually afebrile. It can lead to haemolytic uremic syndrome (haemolytic anaemia, acute renal failure and thrombocytopenia), which is the commonest cause of acute renal failure in children.- Rotavirus: It rarely causes bloody diarrhoea.- Salmonella and Yersinia: While they can cause bloody diarrhoea, they are much less common compared to Campylobacter.

Nissl body is a neuron-specific cellular structure. It is composed of rough endoplasmic reticulum and fine granules. The rough endoplasmic reticulum contains free ribosomes, and are the hub of protein synthesis. When these substances are exposed to a cresyl violet solution, they show selective-staining by turning purple-blue. In pathologic processes, they may undergo chromatolysis.

The most probable diagnosis in this patient is Noonan syndrome.Noonan syndrome is an autosomal dominant condition characterised by short stature, heart defects (mainly pulmonary stenosis) and learning difficulties. An affected foetus can present with a significant increase in the nuchal thickness or a cystic hygroma of the neck. The condition is variable, and an affected parent is often only diagnosed after the diagnosis in the child.

CSF is produced mainly by a structure called the choroid plexus in the lateral, third and fourth ventricles. CSF flows from the lateral ventricle to the third ventricle through the interventricular foramen (also called the foramen of Monro). The third ventricle and fourth ventricle are connected to each other by the cerebral aqueduct (also called the Aqueduct of Sylvius). CSF then flows into the subarachnoid space through the foramina of Luschka (there are two of these) and the foramen of Magendie (only one of these).Absorption of the CSF into the blood stream takes place in the superior sagittal sinus through structures called arachnoid villi . When the CSF pressure is greater than the venous pressure, CSF will flow into the blood stream.

Liddle’s syndrome,  is an autosomal dominant disorder, that is characterized by early, and frequently severe, high blood pressure associated with low plasma renin activity, metabolic alkalosis, low blood potassium, and normal to low levels of aldosterone. Liddle syndrome involves abnormal kidney function, with excess reabsorption of sodium and loss of potassium from the renal tubule. Bartter Syndrome also presents with hypokalaemia, however blood pressure of these patients is usually low or normal.

Intussusception is the invagination of one segment of the intestine within a more distal segment. It presents with vomiting, abdominal pain, and a palpable abdominal mass.Intussusception usually affects infants between 6-18 months old. Boys are affected twice as often as girls

In the prenatal heart, right-to-left atrial shunting of blood through the foramen ovale is essential for proper circulation. After birth, as the pulmonary circulation is established, the foramen ovale functionally closes as a result of changes in the relative pressure of the two atrial chambers, ensuring the separation of oxygen-depleted venous blood in the right atrium from the oxygenated blood entering the left atrium.

A preterm with respiratory distress syndrome presents with the condition as a result of immature lungs and inadequate surfactant production. Management of RDS therefore includes surfactant therapy, oxygen administration and mechanical ventilation, as well as measures such maintaining acid base levels and blood haemoglobin in an intensive care unit. Dexamethasone is not shown to be particularly effective when given to a preterm, but can however be used to prevent or decrease RDS severity when given to the mother before delivery.

History of recurrent infections and failure to thrive (probably due to pancreatic enzyme insufficiency) is highly suggestive of cystic fibrosis. Pseudomonas has been identified as an important respiratory pathogen in patients with cystic fibrosis.

Intussusception is the most suggested case here based on the child’s symptoms. The urgent course of treatment is to bring the child to a paediatric surgical unit. If air reduction attempts fail, surgery will have to be done. Risk factors for intussusception include viral infection and intestinal lymphadenopathy.

Progressive vomiting due to pyloric stenosis leads to hypochloraemic, hypokalaemic, metabolic alkalosis.

Infants may require tracheal intubation if:- direct tracheal suctioning is required- effective bag-mask ventilation cannot be provided- chest compressions are performed- endotracheal (ET) administration of medications is desired- congenital diaphragmatic hernia is suspected, or – a prolonged need for assisted ventilation exists.

When a child with joint problems presents with red-eye, the likelihood of anterior uveitis must be excluded by involving an ophthalmologist in the assessment. This is because uveitis is the most common extra-articular manifestation of juvenile idiopathic arthritis.Other options:- Cataract: It does not give rise to a red-eye, but leukocoria. Often this would have been picked up at an earlier age. – A patient with a corneal foreign body almost would almost invariably give a suspicious history (onset while playing outdoors etc.), as well as have marked symptoms of ocular discomfort (red, watery and painful eyes). – A child with periorbital cellulitis often presents acutely unwell and distressed. – A child with an uncorrected refractive error often complains of being unable to see in class and does not normally present with ocular redness.

Eight percentage of infantile haemangiomas are focal and solitary. Sixty percent of cutaneous haemangiomas occur on the head and neck, 25% on the trunk, and 15% on the extremities. Haemangiomas also can occur in extracutaneous sites, including the liver, gastrointestinal tract, larynx, CNS, pancreas, gall bladder, thymus, spleen, lymph nodes, lung, urinary bladder, and adrenal glands.Guidelines on the management of infantile haemangioma were released in December 2018 by the American Academy of Paediatrics stating that:Imaging is not necessary unless the diagnosis is uncertain, there are five or more cutaneous infantile haemangiomas present, or there is suspicion of anatomic abnormalities.

Projectile vomiting is the hallmark symptom of hypertrophic pyloric stenosis. It is the most common cause of intestinal obstruction in infancy, which has a male-to-female predominance of 4-5:1. Current management recommendations include ultrasonography for diagnosis, correction of electrolytes, and surgical intervention.

Observational studies fall under the category of analytic study designs and are further sub-classified as observational or experimental study designs. The goal of analytic studies is to identify and evaluate causes or risk factors of diseases or health-related events. The differentiating characteristic between observational and experimental study designs is that in the latter, the presence or absence of undergoing an intervention defines the groups. By contrast, in an observational study, the investigator does not intervene and rather simply “observes” and assesses the strength of the relationship between an exposure and disease variable.Three types of observational studies include cohort studies, case-control studies, and cross-sectional studies. Case-control and cohort studies offer specific advantages by measuring disease occurrence and its association with an exposure by offering a temporal dimension (i.e. prospective or retrospective study design). Cross-sectional studies, also known as prevalence studies, examine the data on disease and exposure at one particular time point. Because the temporal relationship between disease occurrence and exposure cannot be established, cross-sectional studies cannot assess the cause and effect relationshipDisadvantage of Cohort study is Susceptible to selection bias.

Jacob is likely to be four years old as demonstrated by his activities throughout the day. Most 4 year olds are able to run well, jump and hop, but find skipping a little more difficult. They are able to brush their teeth and dress themselves with supervision, and go to the toilet alone.

The most probable diagnosis in this patient is lead poisoning.Lead poisoning: While it is not common, it can be potentially fatal. One of the key presenting features here is pica, the ingestion of non-nutritive substances such as soil, soap, paper or wood. Pica can also be observed in children in iron-deficiency anaemia, developmental delay and pregnancy. However, in a child who is exposed to lead in their environment (e.g. from lead paint or pipes), lead poisoning is most likely. It is commonly associated with iron deficiency which in turn increases the lead absorption. Treatment is either with oral D-penicillamine or intravenous sodium calcium edetate.

European guidelines suggest that triple therapy for 1 week is acceptable and sufficient for H. pylori eradication. Although triple therapy for 2 weeks might have higher therapeutic rates, it also carries a higher risk of side effects. Triple therapy includes amoxicillin and clarithromycin and a proton-pump inhibitor, usually omeprazole.

Prader-Willi Syndrome is a genetic disorder that occurs when a chromosome from paternal chromosome 15q is deleted or unexpressed during the formation of the egg or sperm, or in embryonic development. Individuals usually inherit one copy of this gene from each parent, and in this case on the paternal gene remains active in parts of the brain and other organs. This phenomenon is known as genetic imprinting, and is also seen in Angelman’s syndrome. Symptoms seen in Prader-Willi range from poor muscle tone during infancy to developmental and cognitive delays. Many individuals suffer from hypogonadism that affects fertility in both males and females. In Angelman’s syndrome the maternal chromosome 15q is unexpressed. The condition is also called happy puppet syndrome as affected children present with a happy demeanour, ataxic gait, and flapping movements of the limbs.

Distal renal tubular acidosis (dRTA) is characterised by a decreased hydrogen ion excretion from the alpha intercalated cells of the collecting duct of the distal nephron. The resultant acidosis causes Ca and phosphates to be released from bones to buffer the acidosis causing hypercalciuria, thus precipitating calcium compounds in the kidney. Other consequences of the dRTA in children include rickets, hypokalaemia, and polyuria. While dRTA can occur as a result of various pathologies including autoimmune disease, proximal renal tubular acidosis often presents as part of Fanconi’s syndrome. One way to differentiate between the two conditions is with an acid challenge test. In proximal RTA offering the child an acid load will decrease the urinary ph whereas in distal disease the pH will be unaffected due to impairment in hydrogen ion secretion.

Carbon monoxide is a colourless gas, which is toxic to animals. It has a high affinity for haemoglobin (around 250 times greater than oxygen). It combines with haemoglobin forming carboxyhaemoglobin, which decreases the oxygen-carrying capacity of the blood, leading to a left-shift in the oxygen-dissociation curve. CO is produced endogenously in limited amounts (0.4ml per hour), but the toxic levels are higher.

The most likely organism is enterohemorrhagic verotoxin-producing E.coli. It usually causes haemolytic uremic syndrome.

Crohn’s disease rarely manifests in an acute manner.

Polio and giardiasis usually manifest with non-bloody diarrhoea.

Thread worms don’t always cause symptoms, but people often experience itchiness around their bottom or vagina. It can be worse at night and disturb sleep.

Linear regression is a basic and commonly used type of predictive analysis. The overall idea of regression is to examine two things: (1) do a set of predictor variables do a good job in predicting an outcome (dependent) variable? (2) Which variables, in particular, are significant predictors of the outcome variable, and in what way do they–indicated by the magnitude and sign of the beta estimates–impact the outcome variable.These regression estimates are used to explain the relationship between one dependent variable and one or more independent variables. Three major uses for regression analysis are (1) determining the strength of predictors, (2) forecasting an effect, and (3) trend forecasting

The child has experienced the Somogyi phenomenon. It is a phenomenon where there’s a morning rise in blood sugar. Often it occurs as posthypoglycemic hyperglycaemia and follows nocturnal hypoglycaemia. The mechanism is the production of counter-regulatory hormones like glucagon, cortisol and adrenaline, which increase glucose. She can be managed by reducing her evening insulin dosage and increasing complex carbohydrates for supper (evening meal).Type I diabetes mellitus:It is a chronic illness that is characterised by the inability to produce insulin. It is caused by autoimmune destruction of the beta cells in the pancreas and often presents with ketoacidosis.The patient can present with symptoms suggestive of polyuria, polydipsia, and weight loss. There can be periods of islet cell regeneration in these patients, which leads to a ‘honeymoon period’ of remission.Symptoms occur when there is < 20% of islet cell activity left.Insulin therapy is required in almost all children with type 1 diabetes.Most children require multiple insulin injections throughout the day via subcutaneous insulin pumps.Target HbA1c in these patients is 48 mmol/mol according to the updated NICE guidelines.

Key observations in the results:

1. Oxygen Saturation Step-Up:
   • There is a significant step-up in oxygen saturation from the right ventricle (72%) to the pulmonary artery (86%). This suggests the presence of left-to-right shunting of blood.
2. Pressure Differences:
   • The pressure in the pulmonary artery is elevated (53/13 mmHg), indicating pulmonary hypertension.

Differential Diagnosis:

1. Patent Ductus Arteriosus (PDA):
   • PDA can cause increased pulmonary blood flow, leading to a step-up in oxygen saturation in the pulmonary artery. The pulmonary artery pressures can also be elevated due to increased blood flow.
2. Primary Pulmonary Hypertension:
   • Typically presents with elevated pulmonary pressures but does not usually show a step-up in oxygen saturation.
3. Pulmonary Stenosis:
   • Would result in elevated right ventricular pressure but would not explain the step-up in oxygen saturation.
4. Septum Primum Atrial Septal Defect (ASD):
   • Would result in a step-up in oxygen saturation from the right atrium to the right ventricle, not between the right ventricle and pulmonary artery.
5. Tetralogy of Fallot:
   • Characterized by right ventricular outflow tract obstruction, VSD, right ventricular hypertrophy, and an overriding aorta. Oxygen saturation levels would typically be lower in the systemic circulation.

The elemental diet is a medically supervised, sole nutrition dietary management given to individuals with moderate to severe impaired gastrointestinal function for 14-21 days.The diet consists of macronutrients broken down into their elemental form requiring little to no digestive functionality allowing time for the gut to rest. Elemental formulations are believed to be entirely absorbed within the first few feet of small intestine.

External oblique forms the outermost muscle of the three muscles comprising the anterolateral aspect of the abdominal wall. Its aponeurosis comprises the anterior wall of the inguinal canal.

The most common cause of homonymous hemianopia (HH) is a stroke. In this condition there is bitemporal field loss. Lesions posterior to the optic chiasm, in the brain parenchyma are most likely to be the cause of the HH. In this case the retention of central vision indicates that the area of injury may be in the occipital cortex, sparing the occipital pole. The occipital pole receives sensory fibres from the macular, and has a dual blood supply protecting it from total infarction. Lesions of the optic tract can be ruled out as these cause total vision loss in the affected eye. Parietal or temporal nerve lesions cause affect the inferior and superior parts of the visual field respectively causing homonymous quadrantinopias.

Meckel’s diverticulum is a true diverticulum and is the most common congenital anomaly of the GI tract, occurring in about 2% of people. It is caused by incomplete obliteration of the vitelline duct and consists of a congenital sacculation of the antimesenteric border of the ileum. Symptoms are uncommon but include lower GI bleeding, bowel obstruction, and inflammation (diverticulitis). Causes of upper GI bleeding in neonates:Swallowed maternal bloodCoagulopathies including haemorrhagic disease of the new-bornStress gastritis & stress ulcersDrugs (NSAIDs, heparin, indomethacin used for patent duct closure, dexamethasone)Causes of upper GI bleeding in children 1 month to 1 year:GORDGastritis (with or without Helicobacter pylori infection)Crohn diseaseDrugs (NSAIDs)Zollinger-Ellison syndromeCauses of upper GI bleeding in children 1 -2 years:Peptic ulcer diseaseZollinger-Ellison syndromeBurns (Curling ulcer)Head trauma (Cushing ulcer)SepsisCauses of upper GI bleeding in older than 2 years:Oesophageal varices secondary to portal hypertension (most commonly portal vein thrombosis and biliary atresia)Duodenal ulcersOesophagitisGastritisMallory-Weiss tears

Management of acute otitis media should begin with adequate analgesia. Antibiotic therapy can be deferred in children two years or older with mild symptoms. Antibiotics should be prescribed immediately if:- Symptoms lasting more than 4 days or not improving- Systemically unwell but not requiring admission- Immunocompromise or high risk of complications secondary to significant heart, lung, kidney, liver, or neuromuscular disease- Younger than 2 years with bilateral otitis media- Otitis media with perforation and/or discharge in the canaHigh-dose amoxicillin (80 to 90 mg per kg per day) is the antibiotic of choice for treating acute otitis media in patients who are not allergic to penicillin, otherwise erythromycin or clarithromycin should be given.

Shoulder dystocia occurs when the fetal anterior shoulder impacts against the maternal symphysis following delivery of the vertex. Less commonly, shoulder dystocia results from impaction of the posterior shoulder on the sacral promontory. Risk Factors for Shoulder DystociaMaternalAbnormal pelvic anatomyGestational diabetesPost-dates pregnancyPrevious shoulder dystociaShort statureFetalSuspected macrosomiaLabour relatedAssisted vaginal delivery (forceps or vacuum)Protracted active phase of first-stage labourProtracted second-stage labour

Hyperkalaemia is not to evaluate or detect AKI but rather the result of it. If one of the rest of the options is present, then AKI would be suspected.

This is a case of nephrotic syndrome that can be confirmed by the presence of urinary albumin. It should be further investigated by a tissue sample to confirm the diagnosis.

Based on the clinical scenario provided, the most probable diagnosis is Peutz-Jeghers syndrome.Peutz-Jeghers syndrome is an autosomal dominant condition characterised by numerous hamartomatous polyps in the gastrointestinal tract. It is also associated with pigmented freckles on the lips, face, palms and soles.Genetic basis: It follows an autosomal dominant inheritance, and the gene responsible encodes serine-threonine kinase LKB1 or STK11.Classical features of PJS include:- Hamartomatous polyps in the GI tract (mainly small bowel)- Pigmented lesions on lips, oral mucosa, face, palms and soles- Intestinal obstruction, e.g. intussusception- Gastrointestinal bleedingThe treatment is mainly conservative unless complications develop.Note:Hereditary haemorrhagic telangiectasia can also be associated with mucocutaneous lesions and iron-deficiency anaemia, but intestinal polyps are not a feature.

Vagus nerve lesions will affect the gag reflex since the pharyngeal muscles are innervated by it.The vagal nerve (10th cranial nerve ) is a mixed nerve carrying motor efferents and sensory afferents. The nerve conducts five distinct qualities, which are carried along general visceral efferent fibres (parasympathetic innervation of pharyngeal, laryngeal, bronchial, and gastrointestinal mucosa), general visceral afferent fibres (sensory information from the thoracic and abdominal viscera, the aortic body, aortic arch), special visceral afferent fibres (carry the taste of the epiglottal region), general somatic afferent fibres (carry sensation from the external auditory meatus, outer tympanic membrane, back of the ear, part of meninges, pharynx), and along special visceral efferent fibres, which innervate skeletal muscles of the pharynx and larynx. Skeletal muscles innervated by the vagal nerve include the cricothyroid, levator veli palatini, salpingopharyngeus, palatoglossal, palatopharyngeus pharyngeal constrictor, and the laryngeal muscles (except cricothyroid). Innervation of these muscles is involved during speech or opening of the larynx during breathing. Efferent parasympathetic fibres control heart rate, peristalsis, and sweating. Stimulation of the efferent parasympathetic fibres lowers heart rate or blood pressure. 80–90% of the vagal fibres are afferent, only 10–20% are efferent fibresPhysical exam of the 10th cranial nerve includes eliciting the gag reflex (The gag reflex involves a brisk and brief elevation of the soft palate and bilateral contraction of pharyngeal muscles evoked by touching the posterior pharyngeal wall.), to look if the uvula is deviated from the side of the lesion, if there is failure of palate elevation upon phonation, and evaluation of speech impairment.In case of bilateral vagal nerve lesions, heart rate and breath rate may be increased. The somatic sensory function can be assessed by testing the sensibility of the external auditory meatus.

Diagnostic criteria of PCOsAccording to the American Association of Clinical Endocrinologists, at least two of three of the criteria below are required for diagnosis of PCOS after excluding other causes of irregular bleeding and elevated androgen levels.Hyperandrogenism (clinical or laboratory)Oligo- and/or anovulationPolycystic ovaries on ultrasoundDiagnosis of PCOS is possible without the presence of ovarian cysts.Rule out any other causes of hyperandrogenism and anovulation.Blood hormone levels↑ Testosterone (both total and free) or free androgen index↑ LH (LH:FSH ratio > 2:1)Oestrogen is normal or slightly elevated A clinical picture of hyperandrogenism overrules any normal hormone levels and can fulfil a diagnostic criterium of PCOS.

Erythema nodosum is the most common type of inflammation of the subcutaneous fat tissue, referred to as panniculitis. Erythema nodosum appears as painful, erythematous round lumps, usually symmetrically on the anterior aspect of lower extremities. These lesions are self-limiting and tend to resolve within 2-8 weeks without undergoing necrosis. There are various causes of erythema nodosum, but the most important among children is the streptococcal throat infection. Other causes include autoimmune conditions like sarcoidosis, inflammatory bowel disease, mycobacterial infection (TB), and drugs like penicillin and sulphonamides. Coeliac disease is not linked with the formation of erythema nodosum.

Sturge-Weber syndrome (SWS), also called encephalotrigeminal angiomatosis, is a neurocutaneous disorder with angiomas that involve the leptomeninges (leptomeningeal angiomas [LAs]) and the skin of the face, typically in the ophthalmic (V1) and maxillary (V2) distributions of the trigeminal nerve. The hallmark of SWS is a facial cutaneous venous dilation, also referred to as a nevus flammeus or port-wine stain (PWS).Signs and symptoms:SWS is generally diagnosed clinically, based on the typical cutaneous, central nervous system (CNS), and ocular abnormalities associated with it.Neurological signs include the following:Developmental delay/intellectual disabilityLearning problemsAttention deficit-hyperactivity disorderInitial focal seizures progressing to frequent, secondarily generalized seizuresIncreasing seizure frequency and duration despite the use of antiepileptic drugs (AEDs)Increasing duration of a transient postictal deficitIncrease in focal or diffuse atrophy – Determined by serial neuroimagingProgressive increase in calcificationsDevelopment of hemiparesisDeterioration in cognitive functioningPhysical signs of SWS are as follows:Port-wine stainMacrocephalyOcular manifestationsSoft-tissue hypertrophyHemiparesisVisual lossHemianopsiaOcular involvement in SWS may include the following signs:BuphthalmosGlaucomaTomato-catsup colour of the fundus (ipsilateral to the nevus flammeus) with glaucomaConjunctival and episcleral haemangiomasDiffuse choroidal haemangiomasHeterochromia of the iridesTortuous retinal vessels with occasional arteriovenous communications

The Chi-squared test would have been a useful test to compare the proportions in the scenario. However, due to the small sample size, Fisher’s exact test can be applied to analyse the significance of the difference. Adequate information is not given to determine what sample sizes were used to test the efficacy of the treatment, and to tell whether the treatment should be discontinued without further analysis on the data.

The most common etiological agent for retinitis in HIV infected patients is cytomegalovirus (88.63% of retinitis in HIV/AIDS patients). Most patients have a CD4 lymphocyte count less than 50/μL, which can represent the susceptibility to this type of retinitis when lymphocyte count falls below this threshold. The treatment consists of systemic intravenous administration of Ganciclovir or Foscarnet at a first stage of induction, followed by the maintenance treatment with oral administration of Ganciclovir.

Answer: Inflammatory bowel diseaseThe inflammatory bowel diseases (IBDs), including ulcerative colitis and Crohn disease, are chronic inflammatory disorders of the gastrointestinal tract most often diagnosed in adolescence and young adulthood, with a rising incidence in paediatric populations. Inflammatory bowel disease is caused by a dysregulated mucosal immune response to the intestinal microflora in genetically predisposed hosts. Although children can present with the classic symptoms of weight loss, abdominal pain, and bloody diarrhoea, many present with nonclassical symptoms of isolated poor growth, anaemia, or other extraintestinal manifestations.Colorectal Carcinoma (CRC) is rare in patients less than 20 years of age.

The boy presented with mild hypoglycaemia and should be managed at home with fast-acting carbs. He should not sleep immediately. His parents should monitor his blood glucose every hour without letting him sleep in between.

The patient’s symptoms are most likely due to phenytoin intake.Note:Hypertrichosis occurs in 5–12% of patients on phenytoin and is most prominent on the extremities. Other options:- Hypertrichosis is the excess hair growth, whereas hirsutism is the development of male-pattern-dependent hair growth, as seen in polycystic ovarian syndrome. – A Becker’s naevus is associated with localised hypertrichosis in the naevus. – Cyclosporine intake can typically lead to diffuse hair growth that begins within 2–4 weeks of starting the drug. – Hereditary gingival fibromatosis is associated with variable hypertrichosis occurring on the eyebrows, face, limbs and mid-back.

Non-Hodgkin Lymphoma: The history is of enlarged reticuloendothelial system with abnormalities in all 3 cell lines of the bone marrow (pallor, fever and petechiae). The most likely diagnosis is therefore acute (lymphoblastic) leukaemia. Lymphadenopathy may be prominent: mediastinal nodes are characteristic of T-cell leukaemia. In lymphoma the marrow involvement tends to be much less.

The central nervous system comprises of two types of cells| neurons and neuroglial cells. Glial cells are the support cells that serve a number of important functions. Three types of neuroglia comprise the mature nervous system, which are ependymal cells, microglia, and macroglia. The macroglia are of two types oligodendrocytes and astrocytes. Microglia are the neuroglial cells that serve the function of phagocytosis since they are derived from the hematopoietic stem cells and share properties with tissue macrophages. They remove the cellular debris from the site of injury or normal cellular turnover by performing scavenger function.

Bacterial meningitis (including meningococcal meningitis, Haemophilus influenzae meningitis, and staphylococcal meningitis) is a neurologic emergency that is associated with significant morbidity and mortality. Initiation of empiric antibacterial therapy is therefore essential for better outcomes. The patient appears to be suffering from meningitis caused by Staphylococcus aureus. Methicillin would be the drug of choice . It is bactericidal and unlike streptomycin and chloramphenicol it is not associated with toxicity

In the first few years of life the developing sensory inputs are important. Hearing is essential for speech and language development and may be delayed when a child cannot hear. Therefore any child with a family history of hereditary deafness should be screened. From about 4-6months babies are able to laugh and babble when excited or unhappy. By the age of 9 months the child should be able to bring together groups of same sound syllables and be able to say one or two words by the 1st birthday. If a child is unable to babble by 10-12 years, it may indicate hearing impairment. By the age of 2 a child should be able to speak in 1 or 2 word phrases and often repeats phrases used by others, known as Echolalia.

Scaphoid fractures are regarded as fractures that are difficult to heal, so a classification system is needed taking different factors into account that should lead towards proper guidance to the healing time and management of these fractures. Popular classification criteria are Herbert, Russe, and Mayo classification systems. Herbert’s classification system is based on the fracture’s stability and proposes that all complete bicortical fractures (except for tubercle fractures) are unstable. Salter-Harris classification is used for categorizing epiphyseal fractures, while Delbert classification system is reserved for fractures of the proximal femur in children. Fractures of the ankles are classified using Ottawa rules, and Garland classification is used for supracondylar fractures in children.

Biliary atresia is a rare condition that usually becomes symptomatic 2 to 8 weeks after birth. It can be congenital or acquired. Typical symptoms include jaundice, weight loss, dark urine and pale stools.

Transfusion with blood products carries a risk of acute and more chronic adverse reactions. These reactions can either be immune mediated due to a component mismatch, or non immune, underpinned by bacterial or viral contamination. Reactions range from very mild such as urticaria, to life threatening in the case of transfusion-related acute lung injury. In transfusion with packed red blood cells, the most common adverse event is pyrexia, while urticaria is the most common adverse event that follows infusion with FFP.

Most infants have a good heart rate after birth and establish breathing by about 90 s. If the infant is not breathing adequately aerate the lungs by giving 5 inflation breaths, preferably using air. Until now the infant’s lungs will have been filled with fluid.

Acute epiglottitis is a life-threatening disorder with serious implications to the anaesthesiologist because of the potential for laryngospasm and irrevocable loss of the airway. There is inflammatory oedema of the arytenoids, aryepiglottic folds and the epiglottis| therefore, supraglottitis may be used instead or preferred to the term acute epiglottitis.Acute epiglottitis can occur at any age. The responsible organism used to be Hemophilus influenzae type B (Hib), but infection with group A b-haemolytic Streptococci has become more frequent after the widespread use of Hemophilus influenzae vaccination. The typical presentation in epiglottitis includes acute occurrence of high fever, severe sore throat and difficulty in swallowing with the sitting up and leaning forward position in order to enhance airflow. There is usually drooling because of difficulty and pain on swallowing. Acute epiglottitis usually leads to generalized toxaemia. The most common differential diagnosis is croup and a foreign body in the airway. A late referral to an acute care setting with its serious consequences may result from difficulty in differentiation between acute epiglottitis and less urgent causes of a sore throat, shortness of breath and dysphagia.

Minimal change nephrotic syndrome leads to the loss of anti-thrombin III which protects the body from forming venous emboli. It may be triggered by virus, immunisations, medication, non-Hodgkin lymphoma, or leukaemiaCharacterised by oedema, proteinuria, hypoalbuminemia, and hypercholesterolemia.

Hirschsprung’s disease is characterized by congenital absence of the autonomic plexus (Meissner’s and Auerbach’s plexus) in the intestinal wall. Usually limited to the distal colon, it can occasionally involve the entire colon or even the small bowel. There is abnormal or absent peristalsis in the affected segment, resulting in continuous spasm of smooth muscle and partial/complete obstruction. This causes accumulation of intestinal contents and dilatation of proximal segment. Skip lesions are highly uncommon. This disease is seen early in life with 15% patients presenting in first month, 60% by 1 year of age and 85% by the age of 4 years. Symptoms include severe and complete constipation, abdominal distension and vomiting. Patients with involvement of ultra-short segments might have mild constipation with intervening diarrhoea. In older children, symptoms include failure to thrive, anorexia, and lack of an urge to defecate. On examination, an empty rectum is revealed with stool palpable high up in the colon. If not diagnosed in time, it can lead to Hirschsprung’s enterocolitis (toxic megacolon), which can be fulminant and lead to death. Diagnosis involves a barium enema or a rectal suction biopsy. Barium enema shows a transition in diameter between the dilated, normal colon proximal to the narrowed, affected distal segment. It is to be noted that barium enema should be done without prior preparation, which can dilate the abnormal segment, leading to a false-negative result. A 24-hour post-evacuation film can be obtained in the neonatal period – if the colon is still filled with barium, there is a high likelihood of Hirschsprung’s disease. Full-thickness rectal biopsy is diagnostic by showing the absence of ganglion cells. Acetylcholinesterase staining can be done to highlight the enlarged nerve trunks. Abnormal innervation can also be demonstrated by rectal manometry.

In children, food-induced anaphylaxis is the most common trigger and accounts for 37 %–85 % of cases, whereas insect bites/stings account for 5 %–13 % and medications account for 5 %–12 % Despite differences between studies, food allergy is clearly the most common cause of anaphylaxis in children

The most common position of the appendix is the retrocecal position.Note: If a retrocecal appendix is difficult to remove, then mobilisation of the right colon significantly improves access.Other options:The various positions of the appendix are:- Retrocecal (74%)- Pelvic (21%)- Postileal- Subcaecal- Paracaecal- Preileal

Arnold-Chiari malformation type II is one of the congenital hindbrain abnormalities that leads to a disruption of the relationship between different hindbrain structures. It is characterized by congenital hydrocephalus, herniation of cerebellar tonsils into the pinal canal with an enlarged 4th ventricle, spina bifida associated with myelomeningocele, and various levels of denervation atrophy of the muscles of the lower limb. The association of type II Arnold-Chiari with myelomeningocele carries importance from an etiological perspective, forming the basis of CSF escape theory.

The signs and symptoms of vitamin D-dependent rickets begin within months after birth, and most are the same for all types of the condition. The weak bones often cause bone pain and delayed growth and have a tendency to fracture. When affected children begin to walk, they may develop abnormally curved (bowed) legs because the bones are too weak to bear weight. Impaired bone development also results in widening of the metaphysis, especially in the knees, wrists, and ribs. Some people with vitamin D-dependent rickets have dental abnormalities such as thin tooth enamel and frequent cavities. Poor muscle tone (hypotonia) and muscle weakness are also common in this condition, and some affected individuals develop seizures.

Clotrimazole interferes with the ergosterol biosynthesis by decreasing ergosteron I biosynthesis, increasing membrane permeability, and disrupting membrane-bound enzyme systems.Vaginal candidiasis is an extremely common condition. Predisposing factors include:- diabetes mellitus- drugs: antibiotics, steroids- pregnancy- immunosuppression – iatrogenic

The clinical picture suggests that the child is severely dehydrated. IV fluid bolus then IV maintenance fluids is the correct option.

Cricothyroidectomy is done in life threatening condition, where an incision is made in cricothyroid membrane to establish a patent airway.

Broca’s area is usually supplied by branches from the middle cerebral artery and thus will be spared when the anterior cerebral artery is occluded.Note:The two internal carotid arteries and two vertebral arteries form an anastomosis known as the Circle of Willis on the inferior surface of the brain. Each half of the circle is formed by:1. Anterior communicating artery2. Anterior cerebral artery3. Internal carotid artery4. Posterior communicating artery5. Posterior cerebral arteries and the termination of the basilar arteryThe circle and its branches supply the corpus striatum, internal capsule, diencephalon and midbrain.

A cohort study is a particular form of longitudinal study that samples a cohort (a group of people who share a defining characteristic, typically those who experienced a common event in a selected period, such as birth or graduation), performing a cross-section at intervals through time.
The relative risk (RR) or risk ratio is the ratio of the probability of an outcome in an exposed group to the probability of an outcome in an unexposed group. Relative risk is used in the statistical analysis of the data of experimental, cohort and cross-sectional studies, to estimate the strength of the association between treatments or risk factors, and outcomes.

Anorexia nervosa is associated with a decrease in muscle mass, which is one of the primary locations of creatinine metabolism. Due to this, plasma creatinine levels are found to be decreased in patients with anorexia. Other blood chemistry derangements in patients of anorexia nervosa include hypercortisolism, hypoglycaemia, low free T3 levels, and hypercholesterolemia.

The normal human pancreas contains about 1,000,000 islets. The islets consist of four distinct cell types, of which three (alpha, beta, and delta cells) produce important hormones| the fourth component (C cells) has no known function.The most common islet cell, the beta cell, produces insulin.The alpha cells of the islets of Langerhans produce an opposing hormone, glucagon.The delta cells produce somatostatin, a strong inhibitor of somatotropin, insulin, and glucagon.

This is probably a case of protein-induced allergic proctitis, due to dietary protein transmitted through the mother to the breast-fed child. The mother should go on a milk-free and soya-free diet but continue to breast-feed.

The clinical picture suggests that the baby has Beckwith-Wiedemann Syndrome, which predisposes the individual to cancer. The most common childhood tumour that a person with Beckwith-Wiedemann Syndrome may develop is Wilms’ tumour. Typical features include: macrosomia, asymmetric limb growth, macroglossia, neonatal hypoglycaemia, umbilical hernias or other abdominal wall deformities.

The clinical presentation of the boy suggests the involvement of the right frontal lobe.Psychiatric or behavioural disturbances secondary to frontal lobe lesions exhibit lateralisation. The lesions of the left hemisphere are associated with depression, especially if the lesion involves the dorsolateral portion of the prefrontal cortex. Whereas, lesions of the right hemisphere are associated with impulsivity, disinhibition, and aggression, as it is the case with the child in question.Presenting symptoms of lobar dysfunctions:- Frontal lobe: Contralateral hemiplegia, impaired problem solving, disinhibition, and lack of initiative. Broca’s aphasia and agraphia suggest the involvement of the dominant hemisphere.- Temporal lobe: Wernicke’s aphasia (dominant hemisphere involvement), homonymous upper quadrantanopia and auditory agnosia (non-dominant hemisphere involvement).- Parietal lobe: Anosognosia, dressing apraxia, spatial neglect and constructional apraxia are observed when the non-dominant hemisphere is involved. Gerstmann’s syndrome is observed when the dominant hemisphere is involved.- Occipital lobe: Visual agnosia, visual illusions and contralateral homonymous hemianopia.

Ewing’s sarcoma is formed by small, round, blue cells, and is common in children. The usually develop in limbs, and clinical findings include pain and inflammation, with lytic destruction showing up on X-rays.

Precocious puberty is the attainment of normal pubertal biochemical and physical features at an abnormally early age. The age cut-offs commonly used to define precocious puberty are 8 years for females and 9 years for males. Precocious puberty may be central (true) or peripheral (false) based on the aetiology. Central precocious puberty is due to the premature activation of the hypothalamic-pituitary-gonadal axis, which in turn leads to the development of secondary sexual characteristics at an earlier than usual age. The best laboratory investigation to diagnose central precocious puberty is a gonadotropin-releasing hormone stimulation test, which is regarded as the gold standard. It requires the collection of multiple blood samples at different time points to measure FSH and LH levels. If the LH levels increase to >8IU/L after stimulation with GnRH, then the diagnosis of central precocious puberty is confirmed.

The baby is not clearing CO2 normally despite normal oxygenation so we should increase the delta P. Higher delta P will increase tidal volume and hence CO2 removal.After initial resuscitation and stabilization, the following should be the ventilator settings used:Rate: 30-40/minutePeak inspiratory pressure (PIP) – determined by adequate chest wall movement.An infant weighing less than 1500 grams: 16-28 cm H2O.An infant weighing greater than 1500 grams: 20-30 cm H2O. Positive end expiratory pressure (PEEP): 4 cm of H2O OR 5-6 cm if FiO2 > 0.90.FiO2: 0.4 to 1.0, depending on the clinical situation.Inspiratory time: 0.3-0.5 sec.After 15 to 30 minutes, check arterial blood gases and pH.If the PaO2 or the O2 saturation is below accepted standards, the FiO2 can be raised to a maximum of 1.0. If the PaO2 or O2 saturation is still inadequate, the mean airway pressure can be raised by increasing either the PIP, PEEP, inspiratory time or the rate, leaving inspiratory time constant.If the PaCO2 is elevated, the rate or peak inspiratory pressure can be raised.

Ebstein’s anomaly is characterised by apical displacement and adherence of the septal and posterior leaflets of the tricuspid valve to the underlying myocardium, thereby displacing the functional tricuspid orifice apically and dividing the right ventricle into two portions. The main haemodynamic abnormality leading to symptoms is tricuspid valve incompetence. The clinical spectrum is broad| patients may be asymptomatic or experience right-sided heart failure, cyanosis, arrhythmias and sudden cardiac death (SCD). Many Ebstein’s anomaly patients have an interatrial communication (secundum atrial septal defect (ASD II) or patent foramen ovale). Other structural anomalies may also be present, including a bicuspid aortic valve (BAV), ventricular septal defect (VSD), and pulmonary stenosis. The morphology of the tricuspid valve in Ebstein anomaly, and consequently the clinical presentation, is highly variable. The tricuspid valve leaflets demonstrate variable degrees of failed delamination (separation of the valve tissue from the myocardium) with fibrous attachments to the right ventricular endocardium.The displacement of annular attachments of septal and posterior (inferior) leaflets into the right ventricle toward the apex and right ventricular outflow tract is the hallmark finding of Ebstein anomaly.

The trend in the management of splenic injury continues to favour nonoperative or conservative management. In Paediatrics, Blunt splenic injuries with hemodynamic stability and absence of other internal injuries requiring surgery should undergo an initial attempt of Non-operative Management (NOM) irrespective of injury grade.In hemodynamically stable children with isolated splenic injury, splenectomy should be avoided.NOM is contraindicated in the presence of peritonitis, bowel evisceration, impalement or other indications to laparotomy.The vast majority of paediatric patients do not require angiography/angioembolization (AG/AE) for CT blush or moderate to severe injuries.AG/AE may be considered in patients undergone to NOM, hemodynamically stable with sings of persistent haemorrhage not amenable of NOM, regardless with the presence of CT blush once excluded extra-splenic source of bleeding.

Although all of the options may lead to an acute red scrotum, torsion of the hydatid of Morgagni is the most common cause at this age (age 12-16 years).

The patient is suffering from an anaphylactic reaction to the cashew nut he consumed.Anaphylaxis:Anaphylaxis is an acute, rapidly progressing, potentially life-threatening IgE mediated Type I hypersensitivity reaction.It involves the release of mediators from mast cells, basophils and inflammatory cells. It is characterised by oedematous swelling of the airway mucosa giving rise to dyspnoea and respiratory distress.The most common cause of anaphylaxis in children is a food allergy.Risk factors for death in patients with anaphylaxis include asthma, age 11+, peanut allergy, and delay in adrenaline administration.Management of anaphylaxis includes:- Resuscitation – ABCD- Remove the allergen- IM adrenaline is given at ten microgram/kg or Nebulised adrenaline 5ml 1:1,000- IV Hydrocortisone is given at 4mg/kg- pro re nata IV fluid support. – Followed by observation.

Among the options provided, a 1-year-old child will be able to understand object permanence e.g. understands that objects continue to exist even when they can’t be seen, e.g. looking for a fallen toy.At the age of 1 year, children should have developed an accurate pincer grip and be able to see and co-ordinate and manipulate fairly small objects such as a raisin.Gross motor development varies, but the average 1-year-old should be able to stand and cruise around furniture or walk with their hands held but not necessarily walk unaided.Drinking from a cup will become established at around 15 months and scribbling at 18 months.

Fabry disease (Angiokeratoma corporis diffusum) is an X-linked lysosomal disorder which occurs due to deficiency or absence of alpha-galactosidase A (α-GAL A) activity as a result of a genetic mutation in the GLA gene. As Fabry’s disease follows X-linked genetics it manifestis predominantly in men. Ongoing burning, tingling pain and discomfort, known as acroparesthesia, mainly affecting the hands and feet is the most debilitating symptom in childhood.

The median nerve is a peripheral nerve originating in the cervical roots C5–T1 of the brachial plexus. It supplies motor innervation to the anterior forearm flexors, the thenar muscles, and the two lateral lumbricals as well as sensory innervation to the lateral palm and anterior, lateral three and a half fingers. Motor and sensory deficits depend on whether the lesion is proximal (above the elbow) or distal (below the elbow). While proximal lesions present with the “hand of benediction,” distal lesions present with either the “pinch sign” (anterior interosseous nerve syndrome) or, in the case of carpal tunnel syndrome, with mildly impaired thumb and index finger motion. Both proximal lesions and carpal tunnel syndrome result in reduced sensation in the area of the thumb, index and middle finger. Anterior interosseus nerve syndrome does not cause any sensory deficits. Chronic injuries to the nerve result in atrophy of median nerve innervated muscles while acute injuries do not have this feature. Treatment is mostly conservative and focuses on rest and immobilization.

Red blood cells (RBC) have a life span of 120 days in humans.Aging of RBC includes changes in many properties: decreased metabolic activity, morphological alterations, including decreased cell volume and changes in cell shape, and quantitative and qualitative modulations of the surface.

Gastrointestinal polyps are common in children and may result in intussusception due to polyp traction. Treatment is usually surgical with enterotomy and removal of the polyp or of a segment of the bowel.

A 3 year old should be able to match two colours, copy a circle, walk up and down the stairs, and jump up and down. By the time they are 4 they can copy a cross, draw a person with three parts, count to 10, stand on one foot.

Congenital cytomegalovirus infection causes: jaundice, hepatosplenomegaly, petechia, microcephaly, hearing loss and seizures.

ADH primarily acts on the collecting ducts.Other options:- The juxtaglomerular apparatus is the site of renin production.- The proximal tubule conducts isosmotic reabsorption of about 60% of sodium chloride and volume. Most of the glucose, amino acids, potassium and phosphate are absorbed here.- The loop of Henle is the site of 25% of sodium reabsorption. Active Chloride transport provides the basis for the counter current multiplier aiding urinary concentration.- The distal convoluted tubule is impermeable to water and acts via active sodium chloride absorption to dilute urine.

The most probable cause for the patient’s presenting symptoms is Sarcoptes scabeii.Scabies:The boy in the scenario presents with a pruritic rash affecting the palms of the hands, especially in the web spaces between the fingers. Additionally, the fact that his sister is showing similar symptoms is an indication of its infectivity. The female Sarcoptes scabiei var hominis mite burrows into the webs of fingers and the sides of digits as seen in the child.This parasitic skin infestation presents typically with nocturnal itching. Other options:- Herpes simplex virus type 1 (HSV-1): This can affect this age group but would usually present with a vesicular perioral rash with associated erythema. – Human papillomavirus (HPV): Cutaneous human papillomavirus infection causes warts, which can form a dome and fleshy shaped lesions on the palms of the hands, but these are not usually itchy. Similar to the causative agent in the boy, they are contagious.- Poxvirus: These viruses cause molluscum contagiosum which presents as dome-shaped lesions anywhere on the body, rather than specifically in palms of hands or finger webs as seen in the boy. Poxviruses are also very infectious.- Staphylococcal infection: This causes impetigo, which presents with yellow discharge and underlying erythema. Impetigo is not usually itchy and can present on any part of the body, rather than the specific areas seen in the boy.

The embryonic period comprises of the first 8 weeks of pregnancy. It is divided into a preembryonic phase (from the 1st to the 3rd week), in which the three germinal layers arise, and into the embryonic phase proper (from the 4th to 8th week), in which the embryonic organ anlagen arise.

The clinical presentation is suggestive of congenital rubella syndrome. The classic triad of presenting symptoms includes sensorineural hearing loss, ocular abnormalities (cataract, infantile glaucoma, and pigmentary retinopathy) and congenital heart disease (patent ductus arteriosus and pulmonary artery stenosis). Other findings in congenital rubella syndrome include CNS abnormalities (mental retardation, behavioural disorders, encephalographic abnormalities, hypotonia, meningoencephalitis, and microcephaly), hepatosplenomegaly, and jaundice.

Neurogenic shock is a devastating consequence of spinal cord injury (SCI), also known as vasogenic shock. Injury to the spinal cord results in sudden loss of sympathetic tone, which leads to the autonomic instability that is manifested in hypotension, bradyarrhythmia, and temperature dysregulation. Spinal cord injury is not to be confused with spinal shock, which is a reversible reduction in sensory and motor function following spinal cord injury. Neurogenic shock is associated with cervical and high thoracic spine injury. Early identification and aggressive management are vital in neurogenic shock to prevent secondary spinal injury.