Perthes’ disease is a disease of the hip in children. It presents with pain that is typically located in the groin area. The pain is often present only during physical activity. Most children seek medical attention because of limping.

Osgood–Schlatter disease is pain caused by inflammation of the patella tendon at the tibial insertion.

Slipped upper femoral epiphysis occurs classically in adolescence (M:F = 3:2)

Key Observations:

1. Cyanosis and Low Oxygen Saturation:
   • Central cyanosis indicates mixing of oxygenated and deoxygenated blood.
   • The aortic oxygen saturation is low (76%), indicating a significant amount of deoxygenated blood entering systemic circulation.
2. Pressure Analysis:
   • The right ventricle pressure is significantly elevated (110/6 mmHg), suggesting an obstructive lesion like pulmonary stenosis or an increased volume load due to a shunt.
   • The pulmonary artery pressure is low (20/5 mmHg) despite the high right ventricular pressure, suggesting an obstruction to flow from the right ventricle to the pulmonary artery, consistent with pulmonary stenosis.
3. Oxygen Saturation Analysis:
   • There is a notable drop in oxygen saturation from the left ventricle (87%) to the aorta (76%), indicating a mixture of oxygenated and deoxygenated blood in the systemic circulation, suggestive of a right-to-left shunt.

Differential Diagnosis:

1. Pulmonary Stenosis:
   • Supported by elevated right ventricular pressure and low pulmonary artery pressure.
2. Ventricular Septal Defect (VSD):
   • Would typically cause left-to-right shunting, leading to increased pulmonary blood flow and higher oxygen saturation in the right ventricle and pulmonary artery, which is not observed here.
3. Over-riding Aorta:
   • Seen in conditions like Tetralogy of Fallot where the aorta receives blood from both the right and left ventricles, leading to mixed oxygen saturation.
4. Right-to-Left Shunt:
   • The data indicates a right-to-left shunt, with low oxygen saturation in the aorta, suggesting that deoxygenated blood is bypassing the lungs and entering systemic circulation.
5. Aortic Stenosis:
   • Typically presents with high left ventricular pressure and a pressure gradient between the left ventricle and the aorta, which is not observed here.

Conclusion:

Given the data, the most likely abnormalities present in this patient are Pulmonary Stenosis, Right-to-Left Shunt, and Over-riding Aorta. These findings are consistent with a condition like Tetralogy of Fallot, where all these features are present.

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 or ulceration. 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), drugs like penicillin and sulphonamides, and malignancies like some leukemias and lymphomas.

Marfan syndrome is a disorder that affects the connective tissue found throughout the body, Marfan syndrome can affect many systems, often causing abnormalities in the heart, blood vessels, eyes, bones, and joints. The two primary features of Marfan syndrome are vision problems caused by a dislocated lens (ectopia lentis) in one or both eyes and aortic root disease, leading to aneurysmal dilatation, aortic regurgitation and dissection is the main cause of morbidity and mortality in Marfan syndrome.

Retinopathy of prematurity (ROP) affects premature infants. It is a retinal vasoproliferative disease for which current screening guidelines are primarily based on birth weight and gestational age. The disease is first detected by screening at 32-38 weeks of gestation or in infants that are about 6-7 weeks old. Screening consists of dilation of the pupils and observing for dilated vessel.

The most probable diagnosis based on the scenario provided above is hereditary spherocytosis.While jaundice and abdominal pain might make you think of hepatitis or cholecystitis in the first instance, the lack of fever suggests otherwise. The apyrexial presentation is against acute cholecystitis, and the past medical history reveals a chronic type of fatigue and two previous episodes of hepatitis. Furthermore, it is unlikely that the child has contracted infective hepatitis twice and now a third time! The most common cause of hepatitis in childhood is hepatitis A, however the lack of travel history to endemic areas makes this less likely. Hepatitis A is usually a mild, self-limiting disease that never presents with chronic symptoms. The chronicity of his fatigue and the blood results lead towards a haematological diagnosis. This is further substantiated by his low haemoglobin levels, high MCV and high reticulocyte count. Chronic haemolytic anaemia is the most likely cause, and the negative Coombs excludes autoimmune haemolytic anaemia (AIHA). Thus, leaving us with the answer as hereditary spherocytosis.Hereditary spherocytosis is a disorder that makes the cytoskeleton of red cells more fragile and therefore leads to red cell death and splenomegaly. Gallstones are a result of this red cell destruction and increased haem metabolism.

Macrosomia can be defined as either a birth weight greater than 4kg or birth weight greater than 90% for the gestational age. Risk factors for macrosomia include maternal diabetes, excessive gestational weight gain, pre-pregnancy obesity, male gender, ethnicity, and advanced gestational age. Genetic conditions associated with macrosomia are Bardet-Biedl syndrome, Perlman syndrome, Beckwith-Wiedemann syndrome, and Prader-Willi syndrome. Silver-Russell syndrome is associated with intrauterine growth retardation and post-natal failure to thrive.

Pale, bulky, malodorous stools are evidence of fat malabsorption syndrome. The diagnostic test is jejunal biopsy to rule out other differential diagnoses such as celiac disease, giardiasis or Crohn’s disease etc.

The boy is most likely to have sustained an injury to his brachial plexus as a result of upward traction of his arm for an extended period of time. We can rule out the topmost nerve roots of the brachial plexus, C6 and C7 as these supply the larger muscles of the arm responsible for moving the shoulder, the elbow and the wrist. The anatomical structure affected is therefore the T1 nerve root which is responsible for movement of the muscles in the hand. This type of injury is called a Klumpke’s Palsy, which is the result of a hyper-abducted trauma to the arm, damaging the C8 and T1 nerve roots. While the radial and ulnar nerve also innervate the hand, the history given points to Klumpke’s palsy as the best explanation for this mechanism of injury.

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. Central precocious puberty is mostly idiopathic, but other causes include congenital or prolonged, untreated hypothyroidism, congenital or acquired central nervous system pathologies, and several genetic syndromes like Silver-Russell syndrome. The other mentioned choices cause peripheral or false precocious puberty.

A peripheral blood film in iron deficiency anaemia can reveal the following morphologically variant RBCs:- Microcytic cells- Hypochromic cells- Pencil cells- Target cellsOther options:- Schistocytes can be caused by mechanical heart valves. – Rouleaux can be seen in chronic liver disease and malignant lymphoma. – Tear-drop poikilocytes can be seen in myelofibrosis. – Acanthocytes can be seen in liver disease and McLeod blood group phenotype.Pathological red cell forms include:- Target cells: Sickle-cell/thalassaemia, iron-deficiency anaemia, hyposplenism, and liver disease.- Tear-drop poikilocytes: Myelofibrosis- Spherocytes: Hereditary spherocytosis and autoimmune haemolytic anaemia- Basophilic stippling: Lead poisoning, thalassaemia, sideroblastic anaemia, and myelodysplasia- Howell-Jolly bodies: Hyposplenism- Heinz bodies: G6PD deficiency and alpha-thalassaemiaSchistocytes (‘helmet cells’): Intravascular haemolysis, mechanical heart valve, and disseminated intravascular coagulation- Pencil poikilocytes: Iron deficiency anaemia- Burr cells (echinocytes): Uraemia and pyruvate kinase deficiency – Acanthocytes: Abetalipoproteinemia

Marfan syndrome is a disorder that affects the connective tissue found throughout the body, Marfan syndrome can affect many systems, often causing abnormalities in the heart, blood vessels, eyes, bones, and joints. The two primary features of Marfan syndrome are vision problems caused by a dislocated lens (ectopia lentis) in one or both eyes and aortic root disease, leading to aneurysmal dilatation, aortic regurgitation and dissection is the main cause of morbidity and mortality in Marfan syndrome.

Meckel’s diverticulum is a congenital diverticulum of the small intestine. It is a remnant of the omphalomesenteric duct (also called the vitellointestinal duct) and contains ectopic ileal, gastric or pancreatic mucosa.Rule of 2’s- occurs in 2% of the population- it is located 2 feet proximal to the ileocaecal valve- it is 2 inches long- it is 2 times more common in men- there are 2 tissue types involvedIt is typically asymptomatic. Symptomatic presentation indicates inflammation of the diverticulum. The symptoms include:- Abdominal pain mimicking appendicitis- Rectal bleeding- Intestinal obstruction: secondary to an omphalomesenteric band (most commonly), volvulus and intussusceptionManagement:Surgical removal if the neck of the diverticulum is narrow or symptomatic. Surgical options are excision or formal small bowel resection and anastomosis.

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.

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.

Boys and men with Klinefelter syndrome typically have small testes that produce a reduced amount of testosterone (primary testicular insufficiency). Testosterone is the hormone that directs male sexual development before birth and during puberty. Without treatment, the shortage of testosterone can lead to delayed or incomplete puberty, breast enlargement (gynecomastia), decreased muscle mass, decreased bone density, and a reduced amount of facial and body hair. As a result of the small testes and decreased hormone production, affected males are not generally infertile but may benefit from assisted reproductive technologies. Some affected individuals also have differences in their genitalia, including undescended testes (cryptorchidism), the opening of the urethra on the underside of the penis (hypospadias), or an unusually small penis (micropenis).

Bilious (green) gastric aspirate or emesis indicates that the intestines are obstructed below the ampulla of Vater.Gastrointestinal (GI) endoscopy is actually considered an essential diagnostic and therapeutic technique. Upper GI endoscopy in neonatal age allows for exploration of the oesophagus, stomach and duodenum| instead lower GI endoscopy easily reaches the sigmoid-colon junction.

A lumbosacral lipoma is a form of congenital spinal lipoma and can be regarded as a cutaneous marker of dysraphism. It is not a skin condition but rather represents a defect in the process of neurulation and leads to a constellation of other abnormalities. The most common other systemic abnormalities associated with midline lumbosacral lipoma include complex anorectal and urological malformations. Other mentioned conditions are benign rashes or birthmarks.

Recurrent bacterial infections may be due to lack of B-cell function, consequently resulting in a lack of gamma globulins production. Once the maternal antibodies have depleted, the disease manifests with greater severity and is called x-linked agammaglobulinemia also known as ‘X-linked hypogammaglobulinemia’, ‘XLA’ or ‘Bruton-type agammaglobulinemia. it is a rare x linked genetic disorder that compromises the bodies ability to fight infections.
Acute leukaemia causes immunodeficiency but not so specific.
DiGeorge syndrome is due to lack of T cell function.
Aplastic anaemia and EBV infection does not cause immunodeficiency.

Based on the clinical scenario provided, this patient most probably has impacted gall stones. Gall stones in children can be caused by haematological diseases such as sickle cell anaemia and thalassemia. Cholesterol stones are also becoming more prevalent. A dilated common bile duct (> 10mm in adults) suggests gall stone impaction. The presence of pyrexia indicates cholecystitis.

Fluid replacement therapy should be initiated immediately because the patient is suffering from severe dehydration as shown by the low urine output, the dry mucous membranes and the low skin turgor.

Infants exposed to maternal HIV and with positive results require immediate management with co-trimoxazole prophylaxis, regardless of their CD4 levels. Antiretroviral treatment is necessary as well but it could wait until further work-up is complete.

Topical benzoyl peroxide is used for the treatment of mild to moderate acne vulgaris. It is actually a peeling agent and it clears the pores and reduces the bacterial cell count.

Congenital LQTS arises from mutations in genes that code for ion channels within myocytes.These mutations all cause ventricular action potentials to be prolonged, resulting in a lengthened QT interval on ECG. The congenital long-QT syndrome (LQTS) is a life-threatening cardiac arrhythmia syndrome that represents a leading cause of sudden death in the young. LQTS is typically characterized by a prolongation of the QT interval on the ECG and by the occurrence of syncope or cardiac arrest, mainly precipitated by emotional or physical stress.LQTS type 1Most common type of congenital LQTSDefect: loss of function mutation on the KCNQ1 gene located on chromosome 11p → defective slow delayed rectifier voltage-gated potassium channelSubtypesJervell and Lange-Nielsen syndrome Associated with congenital deafnessAutosomal recessiveAssociated with ventricular tachyarrhythmiasRomano-Ward syndrome No associated deafnessAutosomal dominantAssociated with ventricular tachyarrhythmias

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.

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.

This child has pseudo hypoparathyroidism. It is a heterogeneous group of rare endocrine disorders characterized by normal renal function and resistance to the action of parathyroid hormone (PTH), manifesting with hypocalcaemia, hyperphosphatemia, and increased serum concentration of PTH.Patients with pseudo hypoparathyroidism type 1a present with a characteristic phenotype collectively called Albright hereditary osteodystrophy (AHO). The constellation of findings includes the following:Short statureStocky habitusObesityDevelopmental delayRound faceDental hypoplasiaBrachymetacarpalsBrachymetatarsalsSoft tissue calcification/ossificationThe goals of therapy are to maintain serum total and ionized calcium levels within the reference range to avoid hypercalcaemia and to suppress PTH levels to normal. This is important because elevated PTH levels in patients with PHP can cause increased bone remodelling and lead to hyper-parathyroid bone disease.The goals of pharmacotherapy are to correct calcium deficiency, to prevent complications, and to reduce morbidity. Intravenous calcium is the initial treatment for all patients with severe symptomatic hypocalcaemia. Administration of oral calcium and 1alpha-hydroxylated vitamin D metabolites, such as calcitriol, remains the mainstay of treatment and should be initiated in every patient with a diagnosis of pseudo hypoparathyroidism.

Administration of IV prostaglandin/PGE1 (e.g., alprostadil) is indicated in ductal-dependent CHDs until surgery can be performedMechanism: prostaglandin prevents the ductus arteriosus from closing → creates intentional shunt to allow mixing of deoxygenated with oxygenated blood.

Unconjugated bilirubin is conjugated to glucuronic acid in the hepatocyte. Conjugated bilirubin passes into the enterohepatic circulation and the bilirubin which evades this system is metabolised by bacteria, primarily in the large intestine, to urobilinogen, then stercobilinogen and eventually oxidised to stercobilin. Stercobilin gives faeces its brown colour.

Haemolytic Uremic Syndrome affects children and is characterised by abdominal pain, a purpuric rash over the body, generalized pallor, haematuria and bloody diarrhoea. There is always a history of preceding diarrhoea caused usually by E.coli and it affects the renal system causing haematuria and deranged renal function tests.