Because the medical history included tonsillitis followed by haematuria and hypertension, there is a strong suspicion of a case of post-streptococcal glomerulonephritis (PSGN). Patients with PSGN usually have serological findings showing depressed serum haemolytic component CH50 and serum concentrations of C3. Sometimes depressed C4 levels are also apparent, but not always, therefore, the answer to this question is: depressed CH50 level.

Alpha-fetoprotein (AFP) is a plasma protein produced by the embryonic yolk sac and the fetal liver. AFP levels in serum, amniotic fluid, and urine functions as a screening test for congenital disabilities, chromosomal abnormalities, as well as some other adult occurring tumours and pathologies.Pregnant maternal serum AFP levels are elevated in:- Neural tube defects (e.g., spina bifida, anencephaly)- Omphalocele- Gastroschisis- posterior urethral valves- nephrosis- GI obstruction- teratomas

The presenting features with the positive pregnancy test are highly suggestive of gestational diabetes mellitus.Diabetes Insipidus:It is much less common than gestational diabetes mellitus. It is characterised by the inability to concentrate urine, with marked thirst.Presenting symptoms include polydipsia (>3L daily), polyuria, nocturia, nocturnal enuresis.Physical examination may reveal features of dehydration and an enlarged bladder.Investigations include biochemical analysis for electrolytes, urine and plasma osmolality, fluid deprivation test, and cranial MRI.The main differential diagnosis is for diabetes insipidus is psychogenic polydipsia.There are three broad categories of diabetes insipidus (DI): – Central (cranial) DI: It is the most common form of diabetes insipidus.It occurs due to decreased secretion of ADH. It usually occurs due to hypothalamic disease and may show response to low-dose desmopressin.- Peripheral (nephrogenic) DI:It is characterised by the resistance of the kidney to ADH.It usually does not respond to low-dose desmopressin.- Gestational DI:It is rare and is mostly seen in teenage pregnancy.It usually presents in the third trimester and often resolves 4-6 weeks post-partum.

Alopecia areata is seen in 6-8.8% of patients with Down syndrome, but only 0.1% of patients with alopecia areata have Down syndrome. The high frequency of alopecia areata in patients with Down syndrome suggests that a genetic linkage for alopecia areata may exist on chromosome 21.

Craniopharyngiomas (also known as Rathke pouch tumours, adamantinomas or hypophyseal duct tumours) affect children mainly between the age of 5 and 10 years. It constitutes 9% of brain tumours affecting the paediatric population. These are slow-growing tumours which can also be cystic, and arise from the pituitary stalk, specifically the nests of epithelium derived from Rathke’s pouch. Histologically, this tumour shows nests of squamous epithelium which is lined on the outside by radially arranged cells. Calcium deposition is often seen with a papillary type of architecture.ACTH-secreting pituitary adenomas are rare and mostly microadenomas. Paediatric astrocytoma’s usually occur in the posterior fossa. Although null cell adenomas can cause mass effect and give rise to the described symptoms, they are not suprasellar. Prolactinomas can also show symptoms of headache and disturbances in the visual field, however they are known to be small and slow-growing.

The patient’s clinical presentation is highly suggestive of Charcot-Marie-Tooth syndrome.It is a hereditary sensory and motor neuropathy. It is also the commonest cause of inherited peripheral neuropathy. The lower motor neuron signs are usually mild in childhood, the age of onset is very variable, and the distal weakness can take years to progress. It is not fatal and does not affect the normal life expectancy.

Tuberous sclerosis presents with the growth of numerous noncancerous (benign) tumours in many parts of the body. They may appear in the brain, kidneys, skin or various other organs.

Certain lesions present on x-ray are suggestive of child abuse including rib, humerus and skull fractures. It is the doctors responsibility to follow up on these cases to determine whether domestic abuse has occurred.

Burkitt lymphoma is associated with the c-myc gene translocation, usually t(8;14). Burkitt lymphoma is a rare high-grade non-Hodgkin lymphoma endemic to west Africa and the mosquito belt. It has a close association with the contraction of Epstein-Barr virus (EBV). Burkitt lymphoma often presents with symmetrical painless lymphadenopathy, systemic B symptoms (fever, sweats, and weight loss), central nervous system involvement, and bone marrow infiltration. Classically in the textbooks, the patient also develops a large jaw tumour.Other aforementioned options are ruled out because:1. t(9;22)-Chronic myeloid leukaemia2. t(15;17)-Acute promyelocytic leukaemia3. t(14;18)-Follicular Lymphoma4. t(11;14)-Mantle Cell Lymphoma

Compared to the rest of the options, Meckel’s diverticulum with ectopic gastric mucosa seems to be the most probable diagnosis, as it can lead to fresh bleeding.Fresh red bleeding can be caused by haemorrhoids, polyps or a massive GI bleed.

Protein energy malnutrition often presents in two common forms, Kwashiorkor and Marasmus. Kwashiorkor is characterised by a protein deficiency with an additional inadequate calorie intake. As a result, affected children present with oedema, muscular atrophy, and their weight for age is 60-80% of the expected weight. Their cutaneous tissue is however preserved. Marasmus on the other hand is characterised by a severe calorie deficiency leading to atrophy of the muscles and adipose tissue, with weight loss being less than 60% of the normal. In both cases, if the child is not promptly rehabilitated, the malnutrition could cause irreversible damage, such as hepatic, cardiac and renal impairments.

Based on the clinical scenario, the most likely risk factor in this child to develop gallstones is sickle cell disease.Note:Haemolysis is the most frequent cause for gallstones in children and the likeliest cause because of his ethnicity would be sickle cell disease. The gallstones are pigmented which form from bilirubin. 70% of patients with sickle cell disease will develop gallstones; the prevalence of gallstones is related to the rate of haemolysis.Other options:- Gilbert’s syndrome: it is a common condition in which bilirubin glucuronidation (i.e. converting bilirubin into a water-soluble form) is affected. During times of stress (viral illness, fasting, etc.) there is an excess bilirubin production, and jaundice may develop. It is a benign condition but there is some evidence of an increased risk of developing gallstones. However, sickle cell disease is a more likely risk factor in this case.- Hereditary spherocytosis: Hereditary spherocytosis is a disease of the white population and is less likely to be the underlying cause in this case.- Male gender: After puberty, the incidence of gallstones is higher in women. Before puberty, the incidence is equal.- Obesity: Obesity is a risk factor for gallstones and is thought to be behind the rising incidence among young adults. Nevertheless, haemolytic states remain the most common reason for gallstones in children.

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 presentation, the patient is probably a case of Crohn’s disease. The first-line treatment of Crohn’s disease is exclusive enteral nutrition.Exclusive enteral nutrition (EEN)This involves drinking a protein-based formula exclusively for 6-8 weeks. It has been shown to have superior mucosal healing when compared with steroids. Furthermore, it is nutritionally advantageous when compared to steroids and does not have the side-effect profile of steroids.Other options:- Intravenous steroids: This is the first-line treatment for ulcerative colitis (UC) or Crohn’s disease if there is rectal disease (which is not the case here). Side-effects include adrenal suppression, behavioural effects, osteopenia and changes in adipose tissue distribution.- Oral steroids: This can be used if EEN is not possible. However, the side-effect profile is less favourable and is not as effective concerning mucosal healing.- Parental nutrition and surgery: They may be occasionally required in severe cases that have failed first-line therapy.

The drainage of cerebral spinal fluid from the third ventricle to the fourth ventricle is carried out by the cerebral aqueduct. The cerebral aqueduct is the narrowest passageway in the entire ventricular system and thus forms the most common site of blockage of flow of cerebrospinal fluid. The interventricular foramen allows passage of CSF to the third ventricle. The foramen of Luschka and Magendie are located on the fourth ventricle and allow passage of CSF to the subarachnoid space from the ventricular system. The pontine cistern is a space located on the ventral aspect of the pons. The cisterna magna is an opening on the subarachnoid space between the pia matter and the arachnoid.

Intussusception is one of the common causes of intestinal obstruction in children, resulting from the invagination or telescoping of one segment of the bowel into the other distal segment. It may induce bowel ischemia and necrosis, as well. It can occur as a complication of Meckel’s diverticulum. It usually occurs proximal to the ileocecal valve, and the most common presentation is ileocecal. Early signs and symptoms include cramping abdominal pain, nausea, vomiting, and pulling legs up to chest area. First line treatment includes resuscitation with IV fluids and nasogastric tube. It responds well to air-enema, which is also diagnostic.

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.

Complement activation plays a key role in the pathophysiology of SLE and it is recommended to continue monitoring serum levels of C3 and C4 to assess for disease activity. However, it is important to note that decreased serum complement is not consistently associated with disease flares.

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.

ASD is an acyanotic congenital heart disease, characterized by the failure of the interatrial septum to form completely, which results in the mixing of left and right-sided blood. There are various types of ASD, some of them are ostium primum septal defect and patent foramen ovale. Clinical findings associated with ASD are a systolic ejection murmur, fixed splitting of second heart sound, prolonged PR interval, both left and right axis deviation (primum and secundum ASD, respectively). The most common finding is an incomplete right bundle branch block.

The mnemonic STUMPED is helpful for remembering the differential diagnosis for congenital corneal opacities: – Sclerocornea- Tears in Descemet membrane (usually due to forceps trauma or congenital glaucoma)- Ulcers (e.g. infection – rubella)- Metabolic (e.g., mucopolysaccharidosis)- Peters anomaly- oEdema – Dermoids (e.g. Goldenhar’s syndrome)

The post-ingestion plasma level, which is required in order to guide the treatment, reaches a peak at 4 hours. Levels requiring antidote (N-acetyl cysteine) include: 100 mcg per ml at 4 hours, 35 mcg per ml at 10 hours and 25 mcg per ml at 12 hours. These levels are in conjunction with the levels recorded and they should all be put down on a treatment nomogram.

All of the presenting features of the child are suggestive raised intracranial pressure. Thus, urgent treatment with 20% Mannitol can improve the child’s condition. Mannitol is an osmotic diuretic that is used in the treatment of raised intracranial pressure. It should be avoided in hypovolaemia because of its diuretic effects. Other options:- Head up at 15°: Keeping the head up at 20° in the midline will aid venous drainage. – Maintain CO2 at 5 kPa: If there is an acute rise in intracranial pressure, then lowering the CO2 to 4-4.5 kPa as a temporary measure can be beneficial. However, this must be only short-lived since it causes vasoconstriction and can impair cerebral blood flow. – 10% glucose bolus: Maintaining normoglycemia in traumatic brain injury is important. – 0.9% saline infusion: Hypertonic saline infusion of 3% can reduce intracranial pressure. 0.9% saline as a bolus could be beneficial if there were hypotension.

Hypercalcemia refers to increased serum calcium levels and is characterized by a number of significant constellations, including polyuria, muscle weakness, abdominal pain, fatigue, and cardiac arrhythmias. The causes of hypercalcemia can be classified as PTH-dependant causes and PTH-independent causes. The causes can be both congenital and acquired. The most common cause of PTH-dependent hypercalcemia is the primary or tertiary hyperparathyroidism, resulting from parathyroid gland tumours. Hyperparathyroidism is also associated with chronic renal failure. PTH-independent hypercalcemia is caused by William’s syndrome, hypervitaminosis (vitamin A and D intoxication), endocrinopathies (hyperthyroidism), various drugs (thiazide diuretics), and some inborn errors of metabolism. One of the congenital causes of PTH-independent hypercalcemia is idiopathic infantile hypercalcemia.

Bone marrow failure syndromes are characterized by the bone marrow’s inability to produce cells of different lineage. They can be classified as those affecting one or two cell lineages or those affecting all three of them. Fanconi syndrome, along with dyskeratosis congenita, is one of the inherited bone marrow failure syndromes that causes pancytopenia. Other inherited disorders affecting hematopoietic lineage include Diamond-Blackfan anaemia, Schwachman-Diamond syndrome, congenital amegakaryocytic thrombocytopenia (CAMT) and Thrombocytopenia absent radii (TAR) syndrome. Acquired causes of bone marrow failure that lead to pancytopenia include aplastic anaemia, drugs, nutritional deficiencies, and viral infections. Kostmann syndrome is an autosomal recessive form of severe neutropenia, most likely due to excessive neutrophil apoptosis.

Possible complications include:- Hearing loss (which may be partial or total)- problems with memory and concentration- problems with coordination and balance- learning difficulties (which may be temporary or permanent)- epilepsy (Seizures)- cerebral palsy- speech problems- vision loss (which may be partial or total)As hearing loss is the most common complication of meningitis people recovering from the condition are usually given a hearing test to assess their hearing.

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.

Meconium ileus equivalent (MIE) can be defined as a clinical manifestation in cystic fibrosis (CF) patients caused by acute intestinal obstruction by putty-like faecal material in the cecum or terminal ileum. A broader definition includes a more chronic condition in CF patients with abdominal pain and a coecal mass which may eventually pass spontaneously. The condition occurs only in CF patients with exocrine pancreatic insufficiency (EPI). It has not been seen in other CF patients nor in non-CF patients with EPI. The frequency of these symptoms has been reported as 2.4%-25%. The treatment should primarily be non-operative. Specific treatment with N-acetylcysteine, administrated orally and/or as an enema is recommended. Enemas with the water soluble contrast medium, meglucamine diatrizoate (Gastrografin), provide an alternative form for treatment and can also serve diagnostic purposes. It is important that the physician is familiar with this disease entity and the appropriate treatment with the above mentioned drugs. Non-operative treatment is often effective, and dangerous complications following surgery can thus be avoided.

Erythema multiforme is a skin rash characterized by the eruption of macules, papules, and target-like lesions. The target or iris lesions appear rounded with a red centre surrounded by a pale ring, which in turn is surrounded by a dark red outer ring. These are acute and self-limiting, mostly appearing on the distal extremities along with palmoplantar involvement. The disease affects the mucous membrane and orbits as well. The most common infectious cause is herpes simplex virus 1 and 2 to a lesser extent. Inflammation of the adipocytes underlying the skin is referred to as erythema nodosum, and it is not a feature of EM.

Acute lymphoblastic leukaemia (ALL) is a cancer of the lymphoid line of blood cells characterized by the development of large numbers of immature lymphocytes. Symptoms may include feeling tired, frequent infections with fever as well as anaemia with thrombocytopenia. As an acute leukaemia, ALL progresses rapidly and is typically fatal within weeks or months if left untreated. The patient’s age also favours the diagnosis of ALL as it occurs most commonly in children, particularly those between the ages of two and five.