In the Hirschberg test, the corneal reflex should fall in the same place in both eyes. If there is a malalignment then the reflection of the light will appear in different places in the two eyes. The cover test is then used to differentiate between a latent deviation, or a manifest deviation.In the Bruckner test, the direct ophthalmoscope is used to obtain a red reflex simultaneously in both eyes. If strabismus is present, the deviated eye will have a lighter and brighter reflex than the fixating eye.The swinging flashlight test is a test of the pupils response to light, and to check for a relative afferent pupillary defect (RAPD).The Angle Kappa test measures the angle between the line of sight and the corneal-pupillary axis. It is a monocular measurement.

Aplastic anaemia causes a deficiency of all blood cell types: red blood cells, white blood cells, and platelets. It is more frequent in people in their teens and twenties, but is also common among the elderly. It can be caused by heredity, immune disease, or exposure to chemicals, drugs, or radiation. However, in about one-half of cases, the cause is unknown.The definitive diagnosis is by bone marrow biopsy| normal bone marrow has 30–70% blood stem cells, but in aplastic anaemia, these cells are mostly gone and replaced by fat.First-line treatment for aplastic anaemia consists of immunosuppressive drugs, typically either anti-lymphocyte globulin or anti-thymocyte globulin, combined with corticosteroids, chemotherapy and ciclosporin. Hematopoietic stem cell transplantation is also used, especially for patients under 30 years of age with a related matched marrow donor.

Penetrance is defined as the percentage of individuals having a particular mutation or genotype who exhibit clinical signs or phenotype of the associated disorder or genotype.Gaucher disease is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have mutations. The parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but they typically do not show signs and symptoms of the condition.

Due to breakdown of the red blood cell membrane in haemophilic patients, cholesterol crystals are formed by the lipids. On the other hand lipofuscin deposition does not occur in haemolysis or haemorrhage. Neutrophil accumulation suggests acute inflammation. Anthracotic pigment is an exogenous carbon pigment that deposits in the lung from dust. Russell bodies are intracellular accumulations of immunoglobins in plasma cells. Curschmann’s spirals and Charcot Leyden crystals are pathognomonic of asthma.

Rota virus is the leading cause of vital gastroenteritis among children from 6 months to 6 years of age. It is transferred by feco-oral route and it damages the transport mechanism in the intestinal mucosal cells which leads to electrolyte imbalance that’s why the child suffers from dehydration. Treatment of choice is rehydration and correction of electrolyte imbalance.

Androgen excess is one of the most common causes of advanced bone age. It usually occurs in precocious puberty or congenital adrenal hyperplasia.

The given presentation is highly suggestive of withdrawal effect of ketamine.Ketamine is known for its unique property of inducing dissociative anaesthesia. Emergence phenomenon (as seen in the child in question) is an adverse effect that occurs during recovery from dissociative anaesthesia. The components of emergence phenomenon include a euphoric state associated with hallucinations.

Ventilatory rates of 40-60 breaths/min should be provided initially, with proportionally fewer assisted breaths provided if the infant’s spontaneous respiratory efforts increase. Although this practice has not been extensively studied, initial inflation of the new-born’s lungs with either slow-rise or square-wave inflation to a pressure of 30-40 cm H2 O for approximately 5 seconds has been reported to result in more rapid formation of Functional Residual Capacity (FRC).At the moment of delivery and first breath, the neonatal lung is converting from a fetal non-aerated status to a neonatal status. The neonatal lung requires gas exchange, and this necessitates the development of FRC with the resorption of lung fluid and the resolution of most of the atelectasis. Therefore, initial slow ventilation with more prolonged inspiratory times may be useful to assist in this task, balanced against the need to avoid inappropriate inspiratory pressures.Flow-controlled, pressure-limited mechanical devices are acceptable for delivering PPV. These mechanical devices control flow and limit pressure and be more consistent than bags. Self-inflating and flow-inflating bags remain a standard of care. Laryngeal mask airways are effective for assisted ventilation when bag-mask ventilation and intubation are unsuccessful.

Relative risk = (Incidence in exposed group)/incidence in unexposed group). So in this case RR = (50/100)/(50/200) = 2.

The clinical features and the presentation of this child and the MRI findings are highly suggestive of acute lymphoblastic leukaemia.Anaemia and neutropenia, with a borderline platelet count as well as the tumour infiltration on both femurs on the MRI scan, are suggestive of a widespread Marrow disorder. Based on the age of the patient, acute lymphoblastic leukaemia is more appropriate as it is more common than acute myeloid leukaemia in children and can present with bony pain in this age group.Other options:- Acute myeloid leukaemia: Although this is the most common leukaemia that is seen in adults, it rarely presents in children. – Ewing’s sarcoma: This would usually present in a more unilateral manner, and would only be associated with cytopenia if there was direct bone marrow involvement.- HIV infection: It would be very rare in this group. HIV infection can cause a wide array of signs and symptoms, but we are told that the MRI scan is highly suggestive of tumour infiltration, which would be uncommon in this condition. – Juvenile arthritis: It is much less common. There is also nothing to find on examination, such as swollen or painful joints, which would usually be seen in this condition.

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

Nonspecific triggers of inflammation in patients with atopic dermatitis may include physical or chemical irritants. The following simple measures should be followed in daily life to reduce the frequency and severity of irritant-induced atopic dermatitis flares :Skin care products that contain alcohol and astringents should be avoided.New clothes should be laundered before use to remove formaldehyde and other chemicals.Liquid detergents are preferred over powder detergents for laundering clothes, as liquids are easier to rinse out. A second rinse cycle may also improve removal of residual detergent.Patients should shower immediately after swimming in chlorinated pools and should subsequently apply moisturizer.Fragrance-free skin products that are hypoallergenic or made for sensitive skin may be less irritating than other kinds of skin products.Prenatal and postnatal probiotic supplementation may be helpful in preventing the development of atopic dermatitis in young children. In a 2008 meta-analysis, the most commonly studied probiotic was Lactobacillus rhamnoses GG. Larger, randomized controlled studies are needed to confirm these initial findings.Breastfeeding during the first 4 months of life may reduce the incidence and severity of childhood atopic disease but only modestly and only in those at high risk.

Clinical signs of early pregnancy-Amenorrhoea-Nausea and vomiting -Breast enlargement and tenderness -Hyperpigmentation of the areola and formation of linea nigra: Most likely due to increased levels of melanocyte-stimulating hormone produced by the placenta -Increased urinary frequency-Fatigue-Cravings for or aversions to certain foods-Abdominal bloating and constipation

In secretory OM, effusion in the middle ear is present which does not produce any pain to the patient in comparison to acute OM which produces otalgia. The family members are the ones to notice hearing loss as the patient usually is not aware of it. On otoscopy, the features described in the question are prominent. Otitis externa is usually painful and it also produces an itching sensation. Chronic otitis media is painful and may interfere with balance problems. Cholesteatoma is an abnormal cystic growth in the middle ear that usually discharges foul-smelling fluids and as it grows, otalgia can appear.

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.

Cranial nerve II (CN II or optic nerve) runs along the midline of the ventral surface of the brain and conveys visual information from the retina of each eye to the corresponding region of the primary visual cortex. The right half of the visual field of both eyes is processed by the left half of the retina, while the right half of the retina processes the left half of the visual field. These retinal ganglion cells project myelinated axons, carrying CN II sensory afferent fibres, through the optic chiasm, where optic nerve fibres from the nasal half of each retina decussate to the contralateral side of the brain for processing. After passing through the optic chiasm, the optic nerve becomes the optic tract that synapses to the lateral geniculate nucleus (LGN) of the thalamus and subsequently projects optic radiations to the primary visual cortex (V1) of the occipital lobe. The optic tract also projects to the superior colliculus, pretectal nuclei, and suprachiasmatic nuclei. This part of the optic pathway serves the important light reflex.Due to the anatomical location of the optic chiasm superior to the pituitary gland, a suprasellar extension of a pituitary macroadenoma will lead to compression of the optic nerve fibres decussating at the optic chiasm. Impingement of these nerves prevents visual information from the temporal visual fields of each eye from reaching the processing centres in the brain, leading to peripheral vision loss

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.

The most probable diagnosis based on the clinical presentation is myocarditis secondary to Coxsackie virus infection.Myocarditis is an important cause of acquired heart failure. The other infective causes of myocarditis are influenza and adenoviruses, and bacterial causes as seen with Borrelia burgdorferi (Lyme disease). Rheumatic fever is unlikely if the ASO titres are within normal limits. While pancarditis may occur as part of Kawasaki disease| the patient is unlikely to present in failure.

Coeliac disease is associated with the following conditions:- Dermatitis herpetiformis- Autoimmune disorders (e.g. thyroid disease, pernicious anaemia, diabetes)- IgA deficiency- Small-bowel malignancy, particularly lymphoma, if the gluten-free diet is not followed.Serology testing: The IgA tissue transglutaminase antibody is the most sensitive and specific, compared with the anti-endomysial antibody. However, false negatives will occur in children who are IgA-deficient, and IgA levels should be taken at the same time. Other options:Distal obstruction syndrome, meconium ileus, pancreatitis and rectal prolapse are all gastrointestinal manifestations of cystic fibrosis.

The Chi squared test is used to find the relationship between two variables, determining whether they are not independent of each other. This test of statistical significance allows you to determine the degree of confidence with which you can accept or reject the null hypothesis. The student t test compares the significant differences in data means, while rank correlation, linear regression and the correlation coefficient all help to measure the linear relationship between variables.

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

Absence epilepsy is the most common type of generalized childhood epilepsies. It is mainly idiopathic, but 10-40% of the cases have a positive family history. It is characterized by frequent absence seizures and periods of unconsciousness. The hallmark of absence epilepsy on EEG is the bilaterally synchronous 2–4 Hz spike and wave discharges (SWDs). The average age of onset is around 4-8 years, being more prevalent among girls. Treatment resistance is not common.

The most serious side effects of IV Lorazepam include hallucinations, agitation, confusion, amnesia and muscle weakness.

Guidelines suggest that when hypothermia manifests in the context of a shockable rhythm, it might get harder to defibrillate. Therefore, defibrillation is recommended to occur at temperatures below 30°C, and to be limited in three shocks.

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.

Infective endocarditis (IE) is caused by a bacterial, or fungal infection which damages the heart’s endothelium and can thus lead to changes in heart function, valve incompetencies, possible cardiac failure, as well other associated skin and organ changes. Organisms common in IE include Staphylococcus aureus and Streptococcus viridians. The HACEK organisms (Haemophilus, Actinobacillus, Cardiobacterium, Eikenella, and Kingella species) are common in neonates. The Duke criteria uses 2 major, or 1 major and 3 minor criteria, or 5 minor criteria to diagnose infective endocarditis. Major criteria include:- a positive blood culture and evidence of endocardial involvement. Minor criteria include: – evidence of predisposition (a heart condition of injection drug use)- a fever- vascular phenomena such as Janeway lesions- immunologic phenomena such as Osler’s nodes and Roth’s spots| and- microbiological or serological evidence of active infection.

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

The most common manifestation of Wilms tumour is an asymptomatic abdominal mass| an abdominal mass occurs in 80% of children at presentation. Abdominal pain or haematuria occurs in 25%. Urinary tract infection and varicocele are less common findings than these. Hypertension, gross haematuria, and fever are observed in 5-30% of patients. A few patients with haemorrhage into their tumour may present with hypotension, anaemia, and fever. Rarely, patients with advanced disease may present with respiratory symptoms related to lung metastases.

Based on the clinical scenario, the most probable diagnosis for this patient is maxillary sinusitis.The maxillary sinus drains from its superior aspect, leaving it prone to infections. It is the most commonly affected sinus in sinusitis.Common symptoms of maxillary sinusitis include postnasal discharge, pain, headache and toothache.Radiological imaging may show a fluid level in the antrum.Common organisms causing maxillary sinusitis include Haemophilus influenzae or Streptococcus pneumoniae.Treatment with antral lavage may facilitate diagnosis and relieve symptoms. Antimicrobial therapy has to be continued for long periods. Antrostomy may be needed.Other options:- Frontal sinusitis more commonly causes intracranial complications, but it is still less frequent than maxillary sinusitis.- The petrosal sinus is not a cavity within bone| rather, it is a venous structure located beneath the brain.- Frontoethmoidal sinusitis: It usually presents with frontal headache, nasal obstruction and altered sense of smell. Inflammation may progress to involve periorbital tissues. Ocular symptoms may occur, and secondary CNS involvement brought about by infection entering via emissary veins. CT scanning is the imaging modality of choice. Early cases may be managed with antibiotics. More severe cases usually require surgical drainage.

Lichen sclerosus is a common chronic skin disorder that most often affects genital and perianal areas. LS typically presents with vulval itching and clinical findings of pallor, epidermal atrophy (cigarette paper wrinkling), purpura, and/or erosions.Lichen sclerosus (LS) and lichen planus (LP) are both immunologically mediated diseases with a preference for the genitalia. The main difference between the two conditions is that LP has a propensity to involve the mucous membranes including the mouth and vagina which are rarely affected in LS.