Haemophilia B (also known as Christmas disease) is due to a deficiency in factor IX. Haemophilia A is due to a deficiency in factor VIII.

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

Bulimia nervosa is an eating disorder that involves frequent episodes of binge eating followed by inappropriate purging behaviour. The underlying reason for this behaviour is distorted self-image. Bulimia leads to several medical issues, including various laboratory derangements. Among these deranged laboratory parameters are the hormone cholecystokinin, which is found to be decreased in women having bulimia. It is hypothesized that the bingeing episodes observed in patients with bulimia are due to lower levels of CCK since normal levels of CCK are involved in maintaining satiety and controlling the urge to binge eat.

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.

Trisomy 21 (Down’s syndrome)is a genetic disorder characterized by the presence of an extra copy of chromosome 21 in all the body cells, mostly due to non-disjunction during gametogenesis. Robertsonian translocation occurs only in about 2-4% of the cases. A variety of clinical features are found in trisomy 21 due to multi-system involvement but the hallmark is hypotonia, which is present in almost all the cases of trisomy 21. Different types of leukemias are also found in association with down’s syndrome, but they are not the hallmark. Atlantoaxial subluxation is secondary to hypotonia, which induces joint and ligament laxity. Other clinical findings are hypothyroidism, Alzheimer’s disease, Hirschsprung’s disease, and pulmonary hypertension.

Most experts suggest that parents reassurance in case of infantile gastro-oesophageal reflux (GOR) is a sufficient initial measure that involves education about regurgitation and lifestyle changes.

Addison disease is adrenocortical insufficiency due to the destruction or dysfunction of the entire adrenal cortex. It affects glucocorticoid and mineralocorticoid function. The onset of disease usually occurs when 90% or more of both adrenal cortices are dysfunctional. The most common symptoms are fatigue, muscle weakness, loss of appetite, weight loss, and abdominal pain. Adrenal insufficiency can be caused by autoimmune disease or suddenly stopping steroid medicines used to treat other conditions, among other causes.

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.

Benign intracranial hypertension is characterized by an elevation of the CSF pressure that is not caused by hydrocephalus or any space-occupying lesion. The cause is most likely the decreased absorption of CSF into the dural sinuses. The main symptoms are headache and visual abnormalities. It can lead to blindness if not managed on time. The most important risk factors for BIH are female gender and obesity. The causes of BIH include iron deficiency anaemia, sarcoidosis, Lyme disease, SLE, polycythaemia vera, chronic kidney disease, meningitis, and sleep apnoea.

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.

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.

The most appropriate action in this baby would be to perform HIV PCR and commence cART and PCP prophylaxis if HIV positive.Treatment guidelines for HIV-positive infants state that all should receive combination antiretroviral therapy (cART) and Pneumocystis jiroveci pneumonia (PJP) prophylaxis, irrespective of CD4 count or viral load.

The anti-B antibodies in a patient with blood group A belong to the IgM class of immunoglobulins.Note:IgM is the largest antibody formed of 5 antibodies attached together. This functions to agglutinate or clump antigens. The associated anti-A and anti-B antibodies are usually IgM produced in the first years of life by sensitisation to environmental substances such as food, bacteria, and viruses.Other options:- IgG is the most common antibody. It is a single antibody complex.- IgD is found on the surface of B-lymphocytes.- IgE is bound to tissue cells, especially mast cells and eosinophils.

Answer: Torsion of a testicular hydatidThe appendix testis (or hydatid of Morgagni) is a vestigial remnant of the Müllerian duct, present on the upper pole of the testis and attached to the tunica vaginalis. It is present about 90% of the time. The appendix of testis can, occasionally, undergo torsion (i.e. become twisted), causing acute one-sided testicular pain and may require surgical excision to achieve relief. One third of patients present with a palpable blue dot discoloration on the scrotum. This is nearly diagnostic of this condition. If clinical suspicion is high for the serious differential diagnosis of testicular torsion, a surgical exploration of the scrotum is warranted. Torsion of the appendix of testis occurs at ages 0-15 years, with a mean at 10 years, which is similar to that of testicular torsion.Occasionally a torsion of the hydatid of Morgagni can produce symptoms mimicking those created by a testicular torsion| a torsion of the hydatid, however, does not lead to any impairment of testicular function.Absence of the cremasteric reflex is a sign of testicular torsion. This therefore confirms that the diagnosis is Torsion of a testicular hydatid.

The history is suggestive of a post-traumatic seizure which frequently occurs after moderate or severe traumatic brain injury. Although upgoing plantars can be identified in a post-ictal status, an intracranial bleed has to be excluded. A single seizure cannot be considered epilepsy

Coarctation of the aorta is one of the serious forms of congenital heart diseases characterized by a congenitally narrowed down proximal thoracic aorta. This narrowing is usually located distal to the origin of the left subclavian artery. Coarctation can occur in isolation but can accompany other cardiac lesions, including a bicuspid aortic valve. When the coarctation is located just above the left subclavian artery, raised blood pressure can be noted in the right arm. The most common type of murmur found in coarctation of the aorta is a diastolic murmur of aortic regurgitation due to the presence of a bicuspid aortic valve. Exercise augmented cardiac output is only affected in cases where coarctation of the aorta leads to heart failure. Hypertension persists even after the surgical repair and needs to be closely monitored.

The trigeminal nerve is responsible for the sensory innervation of the head, and the muscles of mastication. The nerve is divided into three branches, the ophthalmic nerve (V1) the mandibular nerve (V2) and the maxillary nerve (V3) which all exit the skull through their respective foramina. An easy way to remember these foramina is with the following mnemonic:Standing Room Only, for V1-V3 respectivelyV1- Superior orbital FissureV2- foramen RotundumV3 foramen Ovale

In the case of anterior nasal bleeds, when the bleeding point is clearly visualised the best management step is cautery, either electrical or chemical.

Multiple endocrine neoplasia type 1 is a rare, autosomal dominant disorder characterized by a higher propensity to develop various endocrine and nonendocrine tumours. The primary endocrine tumours that are a part of this disorder include carcinoid tumours and tumours of parathyroid, enteropancreatic, and anterior pituitary origin. Carcinoid tumours encountered in MEN type 1 are mostly of the foregut region. Non-endocrine tumours found in MEN type 1 include meningiomas and ependymomas, lipomas, angiofibromas, collagenomas, and leiomyomas. The pathogenesis of MEN type 1 is the inactivating mutation of the tumour suppressor gene MEN 1, which encodes the protein menin.

The coeliac axis supplies the liver and stomach and from the oesophagus to the first half of the duodenum. The second half of the duodenum to the first two thirds of the transverse colon is supplied by the superior mesenteric artery. The inferior mesenteric supplies the last third of the transverse colon (approximately from the splenic flexure) to the first third of the rectum. The last two thirds of the rectum are supplied by the middle rectal artery. The greater curvature of the stomach is supplied by branches of the splenic artery, which itself comes from the coeliac axis.

Cranial nerves I, II, and VIII are considered purely afferent nerves since they conduct sensory information from the olfactory region, the retina of the eye, and the inner ear structures, respectively.Cranial nerves III, IV, VI, XI, and XII are considered purely efferent due to their motor output to the orbit, the neck, and the tongue.Cranial nerves V, VII, IX, and X are considered mixed cranial nerves due to the presence of afferent and efferent fibres with both sensory and motor components.

Blood tests do not help in the diagnosis of jaundice except of course by telling the level of jaundice (bilirubin) and providing some corroborative evidence such as autoantibodies, tumour markers or viral titres in the case of hepatitis. Classifying causes of jaundice on the basis of ultrasound provides a quick and easy schema for diagnosing jaundice which is applicable in primary care as well as hospital based practice.

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

History of fever is suggestive of an infective focus. A straight nasal bones excludes a nasal bone fracture. A nasal septal abscess is defined as a collection of pus between the cartilage or bony septum and it is an uncommon disease which should be suspected in a patient with acute onset of nasal obstruction and recent history of nasal trauma.

The red reflex examination is an important part of the paediatric ocular assessment. The red reflex is abnormal in conditions like retinoblastoma, retinopathy of prematurity, cataract, and retinal detachment. Amblyopia is a cortical developmental disorder that results in defective visual inputs to both the eyes. The disorder occurs during the cortical plasticity stage of embryonic development. The red reflex is normal in this case since there is no hindrance to the reflection of light from the ocular media and fundus.

Among the options provided, bradycardia is a feature of raised intracranial pressure.The features of raised intracranial pressure include relative bradycardia and hypertension, altered consciousness, focal neurology and seizures.All other options are signs of shock but not raised intracranial pressure.

Removal of foreign bodies from the ear is indicated whenever a well-visualized foreign body is identified in the external auditory canal. Insects are better extracted with suction than with forceps or hooks. From the given answers, irrigation with warm water is the most suitable answer.

Mild deficiencies of 21-hydroxylase or 3-beta-hydroxysteroid dehydrogenase activity may present in adolescence or adulthood with oligomenorrhea, hirsutism, and/or infertility. This is termed nonclassical adrenal hyperplasia.Late-onset or nonclassical congenital adrenal hyperplasia (NCAH) due to 21-hydroxylase deficiency is one of the most common autosomal recessive disorders. Reported prevalence ranges from 1 in 30 to 1 in 1000. Affected individuals typically present due to signs and symptoms of androgen excess. Treatment needs to be directed toward the symptoms. Goals of treatment include normal linear growth velocity, a normal rate of skeletal maturation, ‘on-time’ puberty, regular menstrual cycles, prevention of or limited progression of hirsutism and acne, and fertility. Treatment needs to be individualized and should not be initiated merely to decrease abnormally elevated hormone concentrations.Normal Ultrasound rules out Turner’s syndrome.

Answer: Oculogyric crisisOculogyric crisis is an acute dystonic reaction of the ocular muscles characterized by bilateral dystonic elevation of visual gaze lasting from seconds to hours. This reaction is most commonly explained as an adverse reaction to drugs such as antiemetics, antipsychotics, antidepressants, antiepileptics, and antimalarials. Metoclopramide is a benzamide selective dopamine D2 receptor antagonist that is used as an antiemetic, with side effects that are seen frequently in children.1 The most common and most important side effects of metoclopramide are acute extrapyramidal symptoms, which require immediate treatment. Acute dystonic reactions occur as contractions of the muscles, opisthotonos, torticollis, dysarthria, trismus, and oculogyric crisis.

Cystic fibrosis is an autosomal recessive inherited disorder that affects the lungs or the pancreas. In the case of an affected child whose parents do not have the disorder but carry one copy of the mutated gene, each sibling has a 50% chance of being a carrier of the disease. They can inherit one copy of the gene from each parent. There is a 25 % chance that the child may inherit both mutated genes and be homozygous for the trait.