Projectile vomiting is the hallmark symptom of hypertrophic pyloric stenosis. It is the most common cause of intestinal obstruction in infancy, which has a male-to-female predominance of 4-5:1. Current management recommendations include ultrasonography for diagnosis, correction of electrolytes, and surgical intervention.

The risk of ischemic stroke in patients using combined oral contraceptives is increased in patients with additional stroke risk factors, including smoking, hypertension, and migraine with aura.

Wolff-Parkinson-White (WPW) syndrome is a pre-excitation syndrome characterised by re-entry tachycardia that most commonly presents as a recurrent supraventricular tachycardia. ECG will show a short PR interval and a prolonged QRS complex.

Developmental dysplasia (DDH) of the hip refers to patients who are born with a dislocated or unstable hip due to abnormal development of the hip. Female infants and first born infants are most likely to present with DDH. Other risk factors for DDH include, breech positioning, oligohydramnios, high birth weight or post date babies.

The chance of having appendicitis again after appendix mass is around 17% in children. While the traditional teachings by Hamilton Bailey recommend following the conservative Ochsner-Sherren regimen followed by an interval appendicectomy six weeks after the discharge of the patient, there remains a looming controversy whether to perform an interval appendicectomy or not.

Itchy skin conditions include:Allergy & anaphylaxisAthletes footAtopic dermatitisContact dermatitisDrug allergyErythema multiformeFolliculitisImpetigoInsect bites, stings, infestationsKawasaki diseaseLichen planusNummular eczemaPityriasis roseaPsoriasisScabiesTinea corporisToxic epidermal necrolysisUrticariaVaricellaViral exanthemNote: Miliaria rubra is itchy, miliaria profunda usually isn’t.

The most appropriate procedure in the surgical management of this child would be to perform an appendicostomy for anterior continence enemas (Malone procedure).Idiopathic constipation leading to faecal incontinence is managed in a stepwise progression, first with laxatives such as movicol, enemas and stronger laxatives and in younger children inter-sphincteric injection of botox may be performed. Following this either anal irrigation or antegrade continence enemas are performed. Appendicostomy for anterior continence enemas allow colonic washouts and thereby rapid achievement of continence.Other options:- Defunctioning Ileostomy: Although an option in extreme cases, an ACE stoma would be more appropriate in this child.- Laparotomy for resection of the megarectum is performed if ACE stoma fails due to megarectum.- Left hemicolectomy is a procedure reserved for slow-transit colons to increase transit time.- Bishop-Koop stoma: It is a procedure of historical significance. It is a way of washing out and managing meconium ileus.

Not uncommonly, children insert a foreign body in their ear canal and do not mention it to their parents. If any pain accompanies purulent drainage, the possibility of a foreign body in the ear canal should be considered. A patient with a foreign body in place will not improve until it is removedOrganic foreign bodies tend to elicit inflammatory reactions. In the ear, they predispose to otitis externa, suppurative otitis media and hearing loss

Congenital heart defects are common (40-50%)| they are frequently observed in patients with Down syndrome who are hospitalized (62%) and are a common cause of death in this aneuploidy in the first 2 years of life.The most common congenital heart defects are the following:- Endocardial cushion defect (43%), which results in atrioventricular septal defect (AVSD)/AV canal defect- Ventricular septal defect (32%)- Secundum atrial septal defect (10%)- Tetralogy of Fallot (6%)- Isolated patent ductus arteriosus (4%).About 30% of patients have more than one cardiac defect. The most common secondary lesions are patent ductus arteriosus (16%), atrial septal defect, and pulmonic stenosis (9%). About 70% of all endocardial cushion defects are associated with Down syndrome.Valve abnormalities, such as mitral valve prolapse or aortic regurgitation may develop in up to 40-50% of adolescents and adults who were born without structural heart disease.

Neonatal hypoglycaemia is a common yet serious condition characterized by blood sugar levels less than 2.2mmol/L during the first 3 days of life and less than 2.5mmol/L later on. There are multiple aetiologies and various risk factors that lead to hypoglycaemia in new-borns like prematurity, sepsis, inborn errors of metabolism, and maternal diabetes- induced hyperinsulinism in the new-born. Among the inborn errors of metabolism, fatty acid oxidation defects can lead to persistent hypoglycaemia in new-borns. One such defect is the medium- chain acyl CoA dehydrogenase deficiency, which is the enzyme needed for the breakdown of medium- chain fatty acids.

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

This is a case of nephrotic syndrome that can be confirmed by the presence of urinary albumin. It should be further investigated by a tissue sample to confirm the diagnosis.

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.

Patent ductus arteriosus is a heart defect that occurs in around 50% of the preterm or low birth weight infants. It is characterized by the failure of the fetal ductus arteriosus to close after birth. There are certain risk factors which predispose an infant to a patent ductus arteriosus. The most important risk factor is trisomy 21 or Down’s syndrome, which is associated with multiple cardiac defects. Other factors are congenital rubella syndrome, birth at high altitudes, and female gender.

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. 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), and drugs like penicillin and sulphonamides. Coeliac disease is not linked with the formation of erythema nodosum.

The presentation is suggestive of nephrotic syndrome. A trial of corticosteroids is the first step in treatment of idiopathic nephrotic syndrome. Diuretics are useful in managing symptomatic oedema. Cyclosporin and cyclophosphamide are indicated in frequently relapsing and steroid dependant disease.

Developmental dysplasia of the hip (DDH) is a spectrum of anatomical abnormalities of the hip joint in which the femoral head has an abnormal relationship with the acetabulum.Plain radiographs are of limited value for diagnosis in the new-born child because the femoral head and acetabulum are largely cartilaginous. Ultrasound scanning is the investigation of choice to evaluate DDH in infants younger than six months of age and is useful to diagnose more subtle forms of the disorder when a clinical exam is equivocal. It is also the only imaging modality that enables a three-dimensional real-time image of a neonate’s hip.

Human breast milk composition is best suited to meet all the growth and development requirements of a baby. It contains numerous biochemicals ranging from macronutrients, micronutrients, minerals, immunoglobulins, inflammatory markers, and growth factors. The major bioactive factors found in human breast milk are: immunoglobulins (IgA, IgG, and IgM), cells (macrophages and stem cells), growth factors (epidermal growth factor, tumour necrosis factor-alpha, transforming growth factor-beta, and vascular endothelial growth factor), cytokines, chemokines, hormones, metabolic hormones, glycans, and mucins.

Although some individuals with Anorexia Nervosa exhibit no laboratory abnormalities, the semistarvation characteristic of this disorder can affect most major organ systems and produce a variety of disturbances. The induced vomiting and abuse of laxatives, diuretics, and enemas can also cause a number of disturbances leading to abnormal laboratory findings.Haematology: Leukopenia and mild anaemia are common| thrombocytopenia occurs rarely.Chemistry: Dehydration may be reflected by an elevated blood urea nitrogen (BUN). Hypercholesterolemia is common. Liver function tests may be elevated.Hypomagnesemia, hypozincaemia, hypophosphatemia, and hyperamylasaemia are occasionally found. Induced vomiting may lead to metabolic alkalosis (elevated serum bicarbonate), hypochloraemia, and hypokalaemia, and laxative abuse may cause a metabolic acidosis. Serum thyroxine levels are usually in the low-normal range| triiodothyronine levels are decreased. Hyperadrenocorticism and abnormal responsiveness to a variety of neuroendocrine challenges are common.In females, low serum oestrogen levels are present, whereas males have low levels of serum testosterone. There is a regression of the hypothalamic-pituitary-gonadal axis in both sexes in that the 24-hour pattern of secretion of luteinizing hormone (LH) resembles that normally seen in prepubertal or pubertal individuals.

Observational studies fall under the category of analytic study designs and are further sub-classified as observational or experimental study designs. The goal of analytic studies is to identify and evaluate causes or risk factors of diseases or health-related events. The differentiating characteristic between observational and experimental study designs is that in the latter, the presence or absence of undergoing an intervention defines the groups. By contrast, in an observational study, the investigator does not intervene and rather simply “observes” and assesses the strength of the relationship between an exposure and disease variable.Three types of observational studies include cohort studies, case-control studies, and cross-sectional studies. Case-control and cohort studies offer specific advantages by measuring disease occurrence and its association with an exposure by offering a temporal dimension (i.e. prospective or retrospective study design). Cross-sectional studies, also known as prevalence studies, examine the data on disease and exposure at one particular time point. Because the temporal relationship between disease occurrence and exposure cannot be established, cross-sectional studies cannot assess the cause and effect relationshipDisadvantage of Cohort study is Susceptible to selection bias.

The sensitivity of a screening test can be described in a variety of ways, typically such as sensitivity being the ability of a screening test to detect a true positive, being based on the true positive rate, reflecting a test’s ability to correctly identify all people who have a condition, or, if 100%, identifying all people with a condition of interest by those people testing positive on the test.The specificity of a test is defined in a variety of ways, typically such as specificity is the ability of a screening test to detect a true negative, being based on the true negative rate, correctly identifying people who do not have a condition, or, if 100%, identifying all patients who do not have the condition of interest by those people testing negative on the test.Sensitivity=[a/(a+c)]×100Specificity=[d/(b+d)]×100a: True positiveb: False Positivec: False negatived: True negative

Henoch-Schönlein purpura (HSP) rashes are commonly found on the legs, feet, and buttocks while Immune thrombocytopenia (ITP) rashes manifest predominantly on the lower legs. HSP happens following a sore throat while ITP usually happens following an URTI or Flu. HSP is an inflammation of a blood vessel (vasculitis) while ITP is immune mediated insufficiency of platelets.

Pyloric stenosis affects infants, typically in the second to fourth weeks of life and is caused most commonly by hypertrophy and thickening of the pylorus. It usually presents with projectile vomiting and failure to thrive. The infant usually has a normal appetite. Features include: ‘projectile’ vomiting, typically 30 minutes after a feed, constipation and dehydration may also be present and a palpable mass may be present in the upper abdomen.

HLA-DR (3 and 4) have been associated with an increased risk for idiopathic diabetes mellitus.Type 1 diabetes has a high heritability compared to type 2Identical twins have a 30-50% risk if their twin has type 1 diabetes

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.

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.

Clotrimazole interferes with the ergosterol biosynthesis by decreasing ergosteron I biosynthesis, increasing membrane permeability, and disrupting membrane-bound enzyme systems.Vaginal candidiasis is an extremely common condition. Predisposing factors include:- diabetes mellitus- drugs: antibiotics, steroids- pregnancy- immunosuppression – iatrogenic

The patient has bloody diarrhoea that sounds like a food poisoning in the clinical scenario. Campylobacter is the most common cause of this in the United Kingdom. This is then followed by Salmonella and Shigella. The symptoms are usually self limiting. This is more likely to be bacterial from the food than a viral gastroenteritis.

Turner syndrome is a genetic disease that affects females. It presents with wide-spread nipples, low hairline, lymphoedema, short 4th metacarpals, high-arched palate, cardiac problems, and horseshoe kidneys.

The organisms most likely to cause post-splenectomy sepsis include:- Streptococcus pneumoniae- Haemophilus influenzae- MeningococciEncapsulated organisms carry the most significant pathogenic risk following splenectomy. Hyposplenism:It may complicate certain medical conditions where splenic atrophy occurs or maybe the result of medical intervention such as splenic artery embolization and splenectomy for trauma. The diagnosis of hyposplenism is difficult, and while there may be peripheral markers of the splenectomised state (e.g. Howell-Jolly bodies), these are neither 100% sensitive or specific. The most sensitive test is a radionucleotide labelled red cell scan.It dramatically increases the risk of post-splenectomy sepsis, particularly with encapsulated organisms. Since these organisms may be opsonized, but this then goes undetected at an immunological level due to loss of the spleen. For this reason, individuals are recommended to be vaccinated and have antibiotic prophylaxis.Key recommendations:- All those with hyposplenism or prior to an elective splenectomy should receive pneumococcal, Haemophilus type b and meningococcal type C vaccines. These should be administered two weeks before or two weeks following splenectomy. The vaccine schedule for meningococcal disease primarily consists of a dose of Men C and Hib at two weeks and then a dose of the MenACWY vaccine one month later. Those aged under two may require a booster at two years. A dose of pneumococcal polyvalent polysaccharide vaccine (PPV) is given at two weeks. A conjugate vaccine (PCV) is offered to young children. The PCV is more immunogenic but covers fewer serotypes. Boosting PPV is either guided by serological measurements (where available) or by routine boosting doses at five-yearly intervals.Annual influenza vaccination is recommended in all cases- Antibiotic prophylaxis is offered to all. The risk of post-splenectomy sepsis is highest immediately following splenectomy. Individuals with an inadequate response to pneumococcal vaccination are another high-risk group. High-risk individuals should be counselled to take penicillin or macrolide prophylaxis. Those at low risk may choose to discontinue therapy. All patients should be advised about taking antibiotics early in the case of intercurrent infections.- Asplenic individuals travelling to malaria-endemic areas are at high risk and should have both pharmacological and mechanical protection.