The patient is most likely suffering from obstructive jaundice. Ultrasound of the abdomen is the superior diagnostic tool in detecting and assessing biliary system obstruction, because it is easy, available, accurate and non-invasive.

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.

The initial symptoms of spasmodic abdominal pain, rectal bleeding and vomiting might point towards intussusception, but the peak incidence is in children aged 6–9 months. Considering that this child has additional symptoms of haematuria, proteinuria and a purpuric rash, it is more likely that the child has Henoch–Schönlein purpura (HSP). HSP is an identifiable cause of intussusception. It is an IgA-mediated, autoimmune hypersensitivity vasculitis that targets the small vessels of the skin, GI tract, kidneys, and joints. It is most commonly seen in children aged 3 – 6years and is twice as common in boys than girls. Preceding viral URTI with low-grade pyrexia is common. The most common organism associated with HSP is, however, Group A streptococcal infection. A purpuric rash is seen on the back of the legs and buttocks and can less frequently, affect the arms. Arthralgia is common (usually knees/ankles) in these patients. Abdominal pain and bloody diarrhoea may occur. And half of the children with HSP have renal involvement. Rarely, it can lead to end-stage renal failure. Treatment includes adequate hydration, occasionally steroids, and other immunosuppressants. The disease can recur in 1 in 3 children.

The clinical picture suggests that the child is severely dehydrated. IV fluid bolus then IV maintenance fluids is the correct option.

CUTANEOUS DISORDERS OR DERMATOSIS ASSOCIATED WITH IBD- Psoriasis- Secondary amyloidosis- Vitiligo- Acquired epidermolysis bullosaIn some cases, non-granulomatous skin disorders occur as a reaction to the intestinal disease. These include:- Pyoderma gangrenosum- Neutrophilic dermatosis / Sweet syndrome, typically with pustules- Pyodermatitis-pyostomatitis vegetans, a purulent erosive dermatosis characterised by snail-track ulcers- Erythema multiforme- Erythema nodosum- Acneiform eruptions including nodulocystic acne, hidradenitis suppurativa and folliculitis- Palisaded neutrophilic and granulomatous dermatitis- Necrotizing and granulomatous small vessel vasculitis.

Maternal smoking is one of the most significant risk factors for pyloric stenosis.Remember the three Ps for Pyloric Stenosis:P – palpable massP – peristalsisP – projectile vomiting

A minority of affected individuals may experience severe liver failure. This happens most frequently in people with Wilson’s disease during adolescence and more commonly in women. These individuals may rapidly develop signs and symptoms of liver disease, often associated with anaemia due to breakdown of red blood cells (haemolysis) and mental confusion. In some patients, liver disease does not reveal itself, and the patient develops neurologic (brain-related) symptoms. Common neurological symptoms of Wilson disease that may appear and progress with time include tremor, involuntary movements, difficulty swallowing (dysphagia), difficulty speaking and poor articulation (dysarthria), lack of coordination, spasticity, dystonic postures, and muscle rigidity. Almost all affected individuals with the neurological symptoms of Wilson’s disease have Kayser-Fleischer rings in their eyes that can be identified by a slit lamp examination.

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.

Colonic Polyposis and neoplasia are often seen in Cowden Syndrome which is a hamartomatous polyposis syndrome. Patients with Cowden syndrome have an increased risk for colorectal cancer.

Children are very prone to dehydration during an episode of gastroenteritis. Dehydration is detected early by increased capillary filling time.

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.

Based on the clinical scenario, the most probable diagnosis is Wilson’s disease. Elevated serum ceruloplasmin levels can confirm the diagnosis.Serum ceruloplasminWilson’s disease causes reduced binding of copper to ceruloplasmin, which is the body’s primary copper carrying protein. As a result, copper cannot be excreted into the bile. Copper, therefore, builds up in the liver, causing toxicity and is secreted into the bloodstream unbound to ceruloplasmin. This free copper is deposited around the body, especially the brain, eyes and kidneys. The genetic defect means that ceruloplasmin is not released into the bloodstream| therefore, ceruloplasmin is low in Wilson’s disease.Other options:- Microscopic evaluation of the hair is performed in Menke’s disease, which is a disease of copper absorption leading to copper deficiency. This causes kinky hair, failure to thrive and neurological symptoms (such as hypotonia).- Magnetic resonance imaging (MRI) scan of the brain: An MRI brain may show features of Wilson’s disease (especially in the basal ganglia), but it is not diagnostic.- Serum ferritin: Serum ferritin becomes high in haemochromatosis. This classically causes cirrhosis, bronzing of the skin, cardiomyopathy and diabetes.- Ultrasound scan of the abdomen: While it is useful in any case of hepatomegaly| it is not going to provide the diagnosis in this case.

European guidelines suggest that triple therapy for 1 week is acceptable and sufficient for H. pylori eradication. Although triple therapy for 2 weeks might have higher therapeutic rates, it also carries a higher risk of side effects. Triple therapy includes amoxicillin and clarithromycin and a proton-pump inhibitor, usually omeprazole.

Breast milk jaundice is thought to be associated with one or more abnormalities in the maternal milk itself. Breast milk jaundice syndrome generally needs no therapy if serum bilirubin concentrations remain below 270 mmol/l in healthy full-term infants. When the serum bilirubin concentration is above 270 mmol/l and rising, temporary interruption of breastfeeding may be indicated.

Hirschsprung’s disease is characterized by congenital absence of the autonomic plexus (Meissner’s and Auerbach’s plexus) in the intestinal wall. Usually limited to the distal colon, it can occasionally involve the entire colon or even the small bowel. There is abnormal or absent peristalsis in the affected segment, resulting in continuous spasm of smooth muscle and partial/complete obstruction. This causes accumulation of intestinal contents and dilatation of proximal segment. Skip lesions are highly uncommon. This disease is seen early in life with 15% patients presenting in first month, 60% by 1 year of age and 85% by the age of 4 years. Symptoms include severe and complete constipation, abdominal distension and vomiting. Patients with involvement of ultra-short segments might have mild constipation with intervening diarrhoea. In older children, symptoms include failure to thrive, anorexia, and lack of an urge to defecate. On examination, an empty rectum is revealed with stool palpable high up in the colon. If not diagnosed in time, it can lead to Hirschsprung’s enterocolitis (toxic megacolon), which can be fulminant and lead to death. Diagnosis involves a barium enema or a rectal suction biopsy. Barium enema shows a transition in diameter between the dilated, normal colon proximal to the narrowed, affected distal segment. It is to be noted that barium enema should be done without prior preparation, which can dilate the abnormal segment, leading to a false-negative result. A 24-hour post-evacuation film can be obtained in the neonatal period – if the colon is still filled with barium, there is a high likelihood of Hirschsprung’s disease. Full-thickness rectal biopsy is diagnostic by showing the absence of ganglion cells. Acetylcholinesterase staining can be done to highlight the enlarged nerve trunks. Abnormal innervation can also be demonstrated by rectal manometry.

One of the features of pyloric stenosis is hypochloraemic, hypokalaemic metabolic alkalosis. In emergency settings, capillary blood gas is the easiest and fastest way to establish a sustainable suspicion of pyloric stenosis. However, all tests are useful for the diagnosis of the condition.

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.

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.

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.

Based on the clinical scenario provided, the most probable diagnosis is Peutz-Jeghers syndrome.Peutz-Jeghers syndrome is an autosomal dominant condition characterised by numerous hamartomatous polyps in the gastrointestinal tract. It is also associated with pigmented freckles on the lips, face, palms and soles.Genetic basis: It follows an autosomal dominant inheritance, and the gene responsible encodes serine-threonine kinase LKB1 or STK11.Classical features of PJS include:- Hamartomatous polyps in the GI tract (mainly small bowel)- Pigmented lesions on lips, oral mucosa, face, palms and soles- Intestinal obstruction, e.g. intussusception- Gastrointestinal bleedingThe treatment is mainly conservative unless complications develop.Note:Hereditary haemorrhagic telangiectasia can also be associated with mucocutaneous lesions and iron-deficiency anaemia, but intestinal polyps are not a feature.