Amoxicillin has high efficacy against haemophilus influenza and streptococcus pneumonia, the most common organisms of otitis media. It is an oral drug with high bioavailability.

The type of significance test used depends on whether the data is parametric (can be measured, usually normally distributed) or non-parametric.
Parametric tests:
Student’s t-test – paired or unpaired*
Pearson’s product-moment coefficient – correlation

Non-parametric tests:
Mann-Whitney U test – unpaired data
Wilcoxon signed-rank test – compares two sets of observations on a single sample
chi-squared test – used to compare proportions or percentages
Spearman, Kendall rank – correlation.

The outcome measured is not normally distributed, i.e. it is non-parametric. This excludes the Student’s t-tests. We are not comparing percentages/proportions so the chi-squared test is excluded. The Mann–Whitney U test is a nonparametric test of the null hypothesis that it is equally likely that a randomly selected value from one sample will be less than or greater than a randomly selected value from a second sample.
This test can be used to investigate whether two independent samples were selected from populations having the same distribution.

One of the options of Psoriasis treatment is vitamin D analogues i.e. calcipotriol. Acne is exacerbated by steroids. Erythema nodosum can be caused by various diseases and the treatment of the primary condition resolves the symptoms. Lipomas requires surgery, whereas Steven-Johnson syndrome requires use of steroids and eliminating the culprit drug, which is one of the most common causes.

Case control studies are observational studies which retrospectively determine whether a patient might have been exposed to a risk factor for a certain disease, as compared to a control group from the general population. They can be used for a range of outcomes as well as rare diseases. One of the biggest problems with this type of study is recall bias. Research subjects may selectively remember factors that are more predictive of the disease outcome when compared to the control group. All studies should have prior power calculations before the study commences.

Pulmonary surfactant is a lipoprotein complex that is responsible for preventing the collapse of alveoli and increasing lung compliance.It is produced in the endoplasmic reticulum and secreted from the lamellar bodies of type 2 pneumocytes.Surfactant is essential for reducing surface tension at the air-water interface in the alveoli, thus preventing the collapse of alveoli during expiration. It is composed of dipalmitoyl phosphatidylcholine (DPPC), which is a phospholipid.In fetal development, production of surfactant begins around 26 weeks of gestation and reaches mature levels by 35 weeks.The deficiency of surfactant can result in neonatal respiratory distress syndrome or hyaline membrane disease, particularly in premature new-born babies.

NICE guidelines suggest that at the premonitory stage (pre-hospital) the patient should receive Diazepam 10−20 mg given rectally, or midazolam 10 mg given buccally. If seizures continue, the patient should receive lorazepam IV.

Unless given IV, a drug must cross several semipermeable cell membranes before it reaches the systemic circulation. Drugs may cross cell membranes by diffusion, amongst other mechanisms. The rate of diffusion of a substance is proportional to the difference in the concentration of the diffusing substance between the two sides of the membrane, the temperature of the solution, the permeability of the membrane and, in the case of ions, the electrical potential difference between the two sides of the membrane.

The Chi-squared test evaluates if two variables are related. The other statistical tests mentioned do not perform this function.

The thyroglossal duct cyst is the most common congenital anomaly of the central portion of the neck. The thyroglossal duct cyst is intimately related to the central portion of the hyoid bone and usually elevates along with the larynx during swallowing. Thyroglossal cysts can be defined as an irregular neck mass or a lump which develops from cells and tissues left over after the formation of the thyroid gland during the developmental stages.

The most common organism responsible for tinea capitis is Trichophyton tonsurans.Tinea is a term given to dermatophyte fungal infections. There are three types of tinea, depending on what part of the body is infected:- Tinea capitis – scalp- Tinea corporis – trunk, legs or arms- Tinea pedis – feetTinea capitis (scalp ringworm):It is a cause for scarring alopecia mainly seen in children.If untreated, it can form a raised pustular, spongy/boggy mass called a kerion.The most common cause of tinea capitis in the UK and the USA is Trichophyton tonsurans.Tinea can also be caused by Microsporum canis acquired from cats or dogs.The diagnosis of tinea capitis and identification of the organism is possible from the skin lesions:- Scalp scrapings and Potassium hydroxide (KOH) mounts.- Wood’s lamp: Microsporum canis produces a green fluorescence under Wood’s lamp examination.Treatment: – Oral antifungals: terbinafine for Trichophyton tonsurans infections.- Griseofulvin for Microsporum infections. – Topical ketoconazole shampoo is recommended for the first two weeks to limit the transmission of the infection.

People with Systemic Juvenile Idiopathic Arthritis (also known as Stills disease) can have recurrent fevers, a macular rash, joint pain, joint deformities, an enlarged liver and/or spleen, and can occasionally have polyserositis, lung involvement or pericardial effusions. Rheumatoid factor and antinuclear antibodies are usually negative. Treatment is with non-steroidal anti-inflammatory drugs (NSAIDs) and the prognosis is better than for adult rheumatoid arthritis.In pauciarticular Still’s disease, antinuclear antibodies are present. Large joints are affected and most patients develop classic features of seronegative spondylarthritis.

Atopic dermatitis (AD), also called atopic eczema, is a common chronic or recurrent inflammatory skin disease and affects 15-20% of children and 1-3% of adults worldwide. It is characterized by acute flare-ups of eczematous pruritic lesions over dry skin.The incidence has increased by 2- to 3-fold during the past decades in industrialized countries.Some of the most valuable AD prevalence and trend data have come from the International Study of Asthma and Allergies in Childhood (ISAAC). This is the biggest (close to 2 million children in 100 countries) and only allergy study that has taken a truly global approach. The strength of the study is the use of a uniformly validated methodology allowing a direct comparison of results between paediatric populations all over the world (http://isaac.auckland.ac.nz/index.html).

People with Gilbert syndrome have a build-up of unconjugated bilirubin in their blood (unconjugated hyperbilirubinemia). In affected individuals, bilirubin levels fluctuate and very rarely increase to levels that cause jaundice. Gilbert syndrome is usually recognized in adolescence. If people with this condition have episodes of hyperbilirubinemia, these episodes are generally mild and typically occur when the body is under stress, for instance because of dehydration, prolonged periods without food (fasting), illness, vigorous exercise, or menstruation. Some people with Gilbert syndrome also experience abdominal discomfort or tiredness. However, approximately 30 percent of people with Gilbert syndrome have no signs or symptoms of the condition and are discovered only when routine blood tests reveal elevated unconjugated bilirubin levels.

Idiopathic hypercalciuria (IH) is the commonest metabolic abnormality in patients with calcium kidney stones. It is characterized by normocalcemia, absence of diseases that cause increased urine calcium, and calcium excretion that is above 250 mg/day in women and 300 mg/day in men. Subjects with IH have a generalized increase in calcium turnover, which includes increased gut calcium absorption, decreased renal calcium reabsorption, and a tendency to lose calcium from bone. Despite the increase in intestinal calcium absorption, negative calcium balance is commonly seen in balance studies, especially on a low calcium diet. The mediator of decreased renal calcium reabsorption is not clear| it is not associated with either an increase in filtered load of calcium or altered PTH levels. There is an increased incidence of hypercalciuria in first-degree relatives of those with IH, but IH appears to be a complex polygenic trait with a large contribution from diet to expression of increased calcium excretion. Increased tissue vitamin D response may be responsible for the manifestations of IH in at least some patients.

The boy is most probably a type 1 diabetic patient. Such a condition can affect the behaviour and psychological state of a young child reflected in their behaviour. The parents should seek the help of a clinical psychologist.

Puberty is when a child’s body begins to develop and change as they become an adult.The average age for girls to begin puberty is 11, while for boys the average age is 12.It’s completely normal for puberty to begin at any point from the ages of 8 to 14. The process can take up to 4 years.

This patient has Wilson’s disease. They Kayser-Fleischer ring (ring that encircles the iris) is diagnostic of this. Low serum copper is seen in Wilson’s disease. With the Kayser-Fleischer ring, this makes all of the other answer choices incorrect.

Non Epileptic attack disorder, also known as psychogenic non epileptic seizures, is a condition characterised by episodes of abnormal movement and behaviours that resemble seizures , but are not caused by electrical activity changes in the brain. It is believed that the disorder is caused by the brain’s response to overwhelming or stressful situations. In Jamila’s case, triggering conditions for her episodes may have been the absence of her mother, and the stress of her upcoming examinations. A diagnosis of generalised epilepsy is unlikely because this would require abnormal movement in all 4 limbs during an episode and a longer period of semi consciousness after. Cataplexy can also be ruled out as it does not involve a loss of consciousness which we see in Jamila’s case. Vasovagal syncope does not correspond with the history as there was no evidence of simultaneous collapse and responsiveness coupled with colour change and near spontaneous recovery when supine. A complex partial seizure may be possible in Jamila’s case, however the history of long duration, her eyes being tightly shut and the differences in presentation between the two episodes makes it less likely.

The clinical presentation and leucocytes on the urine dipstick is suggestive of a urinary tract infection. To confirm the diagnosis, urine should be sent for culture and sensitivity.

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.

The patient is most likely to have Bulimia nervosa. A young girl with a low body mass contributes to the low urea. Hypokalaemia and hyponatraemia are due to vomiting. Her urine sodium is also low.- In Addison’s diseases, there are low levels of sodium and high levels of potassium in the blood. In acute adrenal crisis: The most consistent finding is elevated blood urea nitrogen (BUN) and creatinine. Urinary and sweat sodium also may be elevated. – In Syndrome of Inappropriate Antidiuretic Hormone Secretion (SIADH) there is hyponatremia with corresponding hypo-osmolality, continued renal excretion of sodium, urine less than maximally dilute and absence of clinical evidence of volume depletion.

Based on the clinical scenario, the most likely underlying pathogen is the Epstein Barr virus (EBV).An Epstein Barr virus (EBV) infection most commonly results in upper respiratory tract symptoms with fever and sore throat. Lymphadenopathy is frequently palpable on examination. Splenomegaly may also occur, and for this reason, patients diagnosed with glandular fever should be advised to avoid contact sports for one month following diagnosis. The presence of petechiae on the soft palate is also associated with EBV infection. The vast majority of patients with active EBV infection will develop a widespread rash if given amoxicillin, therefore, phenoxymethylpenicillin (Penicillin V) is recommended for the treatment of a suspected bacterial throat infection to prevent this complication occurring for individuals who have EBV infection.Other options:- Coronavirus: This is one of the causes of the common cold and is frequently responsible for sore throats| however, in this case, the presenting features are more suggestive of an EBV infection.- Group A Streptococcus: Streptococci are classified into two main groups| alpha-haemolytic and beta-haemolytic. Group A Streptococcus belongs to the beta-haemolytic group. Group A streptococcal infection is a common cause of bacterial tonsillitis. It is possible that the child, in this case, had streptococcal tonsillitis and has had a drug reaction to the amoxicillin. However her age, flu-like symptoms and petechiae on her palate all point to an EBV infection and amoxicillin resulting in a rash.- Parainfluenza: Parainfluenza viruses are one of many causes of the common cold and can cause pharyngitis. They are the leading cause of viral croup.- Rhinovirus: Rhinoviruses are one of many causes of the common cold and are frequently responsible for sore throats| however, in this case, are other factors suggesting EBV infection.

Angio-oedema, is the rapid swelling of the skin, mucosa and submucosal tissues. The underlying mechanism typically involves histamine or bradykinin. The version related to histamine is to due an allergic reaction to agents such as insect bites, food, or medications. The version related to bradykinin may occur due to an inherited C1 esterase inhibitor deficiency, medications e.g. angiotensin converting enzyme inhibitors, or a lymphoproliferative disorder.

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.

Coverings of the spermatic cord:Spermatic cord is covered by three concentric layers of fasciae, derived from the layers the of anterior abdominal wall. Developmentally, each covering is acquired as the processus vaginalis descends into the scrotum through the layers of the abdominal wall. The layers are:External spermatic fascia: It is derived from the external oblique muscle. It attaches to the margins of superficial inguinal ring.Cremasteric fascia: It is derived from the internal oblique muscle. It covers the cremaster muscle.Internal spermatic fascia: It is derived from the fascia transversalis (fascia covering the transversus abdominis muscle). It is attached to the margins of the deep inguinal ring.

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

Pityriasis rosea is a common, acute exanthem of uncertain aetiology. Viral and bacterial causes have been sought, but convincing answers have not yet been found. Pityriasis rosea typically affects children and young adults. It is characterized by an initial herald patch, followed by the development of a diffuse papulosquamous rash. The herald patch often is misdiagnosed as eczema. Pityriasis rosea is difficult to identify until the appearance of characteristic smaller secondary lesions that follow Langer’s lines (cleavage lines). Several medications can cause a rash similar to pityriasis rosea, and several diseases, including secondary syphilis, are included in the differential diagnosis. Typically, only symptomatic treatment of pruritus with lotions, oral antihistamines, and/or a short course of topical steroids is necessary.

The main aim of randomisation in a clinical trial is to remove the bias and avoid any potential confounding variables. While in double blind studies both the investigators and the patients are not aware of which group they belong in, being blind is not essential in carrying out a randomized study, nor is it essential that the randomisation be done away from the study centre. A placebo also does not facilitate randomisation, which can be done in single centre and multi-centre trials.

Among the given options, lipoatrophy takes time to develop as it is a long-term complication of insulin therapy. Since it has only been two weeks since the initiation of insulin therapy, it is unlikely to occur so early.The risk of lipoatrophy is reduced with newer insulins and also can be avoided by site rotation.However, anaphylaxis, allergic reactions, infection and abscesses at the site of an insulin pump can occur in this patient as a complication of insulin therapy.

The mesonephric duct is one of the paired embryogenic tubules that drain the primitive kidney (mesonephros) to the cloaca. It also gives off a lateral branch forming the ureteric bud. In both the male and the female the Wolffian duct develops into the trigone of the urinary bladder. When the ducts are exposed to testosterone during embryogenesis, male sexual differentiation occurs: the mesonephric duct develops into the rete testis, the ejaculatory ducts, the epididymis, the ductus deferens and the seminal vesicles.

The likely diagnosis in this case is Haemolytic Uremic Syndrome (HUS), which is generally seen in young children presenting with a triad of symptoms, namely: acute renal failure, microangiopathic haemolytic anaemia, and thrombocytopenia. The typical cause of HUS is ingestion of a strain of Escherichia coli. The laboratory results will usually include fragmented RBCs, decreased serum haptoglobin, reduced platelet count, nonspecific WBC changes, and normal coagulation tests (PTT included).

A surgeon will observe the patient and will decide which procedure he needs.

Osteoid osteoma is a bone forming tumour which affects individuals in the second decade of life. The patient presents with a history of pain in the lower limbs which is mostly at night and responds to NSAIDS. If the pain doesn’t respond to NSAIDS, then other differentials should be considered.

This clinical presentation is highly suggestive of choking. According to the BLS algorithm, the next step in managing a case of choking in a conscious child with an ineffective cough is five back blows.Other options:- Adrenaline intramuscularly: The history is similar to anaphylaxis, but the absence of a rash or oedema and the acute onset make choking more likely in this situation. Thus, adrenaline will not be of use in this patient.- CPR at a ratio of 15:2: Since the child is conscious, it is not advised. If the child were unconscious, you would commence basic life support.- Five abdominal thrusts: In the given scenario, the child is an infant. Abdominal thrusts are avoided in infants due to the risk of intra-abdominal injury.

Doctors must perform an infection screen and treat with intravenous antibiotics for at least 48 hours pending results to prevent neonatal sepsis. Risk factors for neonatal sepsis include rupture of the membranes. Risk factors for neonatal sepsis include rupture of membranes greater than 12–24 hours, intrapartum maternal pyrexia (> 38°C), fetal tachycardia, chorioamnionitis, pre-term birth and maternal colonisation with group B Streptococcus. In this case there are two risk factors: prolonged rupture of membranes, and pre-term birth.

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.

Primitive reflexes are central nervous system responses, many of which disappear as a child matures. Retention of these reflexes may point to atypical neurology such as in cerebral palsy or stroke. However, some persist into adulthood. The stepping reflex is present from birth and normally disappears by 6 weeks, while the moro reflex is present from birth to about 4 months. The asymmetrical tonic neck reflex disappears by about 6 months. Reflexes that persist include the head righting reflex which develops at 6 months, and the parachute reflex which develops at 9 months.

Intrauterine growth restriction refers to the failure of the fetus to grow in accordance with the weeks of gestation. There are two types of growth restriction, symmetrical and asymmetrical. Causes include various genetic abnormalities, fetal infections, maternal health conditions, etc. Risk factors for the development of IUGR include fetal echogenic bowel, maternal age above 40 years, low PAPP-A levels, maternal smoking or cocaine use, etc. Fetal echogenic bowel implies a brighter than usual fetal intestines on ultrasonography. It is a marker associated with trisomy 21, which is a cause of IUGR.

Due to its cholestatic properties, Flucloxacillin can block bile flow through the liver, leading to the accumulation of bilirubin in the blood, giving rise to jaundice. Dark urine is the result of excessive bilirubin in the blood being filtered by the kidney. As the bile doesn’t move into the small intestine, stools are pale.

A teratoma is a tumour containing tissue elements that are similar to normal derivatives of more than one germ layer. They usually contain skin, hair, teeth and bone tissue and are more common in children, behaving as a benign tumour. After puberty, they are regarded as malignant and can metastasise.