Breast milk jaundice is associated with breast-feeding. It typically occurs one week after birth and can sometimes last up to 12 weeks, but it rarely causes complications in healthy, breast-fed infants. The exact cause of breast milk jaundice isn’t known. However, it may be linked to a substance in the breast milk that prevents certain proteins in the infant’s liver from breaking down bilirubin. The condition may also run in families. Breast milk jaundice is rare, affecting less than 3 percent of infants. When it does occur, it usually doesn’t cause any problems and eventually goes away on its own. It is safe to continue breast-feeding.

The baby has duodenal atresia.Presenting symptoms and signs are results of high intestinal obstruction. Duodenal atresia is typically characterized by the onset of vomiting within hours of birth. While vomitus is most often bilious, it may be nonbilious because 15% of defects occur proximal to the ampulla of Vater. Occasionally, infants with duodenal stenosis escape detection of an abnormality and proceed into childhood or, rarely, into adulthood before a partial obstruction is noted. Nevertheless, one should assume any child with bilious vomiting has a proximal GI obstruction until proven otherwise, and further workup should be begun expeditiously.congenital duodenal atresia is one of the more common intestinal anomalies treated by paediatric surgeons, occurring 1 in 2500-5000 live births. In 25-40% of cases, the anomaly is encountered in an infant with trisomy 21 (Down syndrome).

Gastrointestinal polyps are common in children and may result in intussusception due to polyp traction. Treatment is usually surgical with enterotomy and removal of the polyp or of a segment of the bowel.

H. pylori release the enzyme urease that has the ability to split urea releasing nitrogen. This process increases the pH in the gastric antrum making the gastric pH less acidic.Helicobacter pylori:It is a spiral, microaerophilic, gram-negative bacterium. It is one of the most common causes of antral gastritis in children. Ulcers are less common in children compared with adults| however, when they occur, they are more common in the duodenum.The presence of H.pylori can be confirmed by:- Stool antigen test (preferred)- Serology- Endoscopy with biopsy and culture- Rapid urease testsH.pylori gastritis may be associated with:- Iron deficiency anaemia- Gastric malignancy Management:The treatment is with triple therapy- two antibiotics, and an antacid.Treatment failure is often attributed to a possible worldwide increase in macrolide resistance. Interestingly, children have higher antibiotic resistance compared with adults.Note:Zollinger-Ellison syndrome (ZES) causes gastrin-secreting tumours and can present as a part of multiple endocrine neoplasia type 1 (MEN1)- an autosomal dominant disorder.

Primary sclerosing cholangitis (PSC) is a long-term progressive disease of the liver and gallbladder characterized by inflammation and scarring of the bile ducts which normally allow bile to drain from the gallbladder. Early cholangiographic changes can include fine or deep ulcerations of the common bile duct. As PSC progresses, segmental fibrosis develops within the bile ducts, with saccular dilatation of the normal areas between them, leading to the typical beads-on-a-string appearance seen on cholangiography. Although these strictures can be found anywhere on the biliary tree, the intrahepatic and extrahepatic bile ducts are simultaneously involved in the vast majority of cases.

Peutz-Jeghers syndrome (PJS) is an autosomal dominant inherited disorder characterized by intestinal hamartomatous polyps in association with a distinct pattern of skin and mucosal macular melanin deposition (freckles on the lips, face, palms and soles). Patients with Peutz-Jeghers syndrome have an estimated 15-fold increased risk of developing intestinal cancer compared to the general population.Management: conservative unless complications develop.

Based on the given scenario, the most probable diagnosis for this patient is acquired immune deficiency syndrome (AIDS) caused by human immunodeficiency virus (HIV). Thus, the most appropriate investigation to confirm the underlying pathology in this patient would be viral serology. Rationale:The presence of oesophageal candidiasis is highly suggestive of severe immunosuppression. The causes of immunosuppression can be chemotherapy, with haematological malignancy, HIV or inhaled steroids. In patients with HIV, oesophageal candidiasis is part of the spectrum of AIDS-defining illnesses and usually occurs when the CD4 count is < 200 cells/microL. Other AIDS-defining illnesses include PCP pneumonia and CMV infections.Oesophageal Candidiasis:It is characterised by white spots in the oropharynx with extension into the oesophagus. It seldom occurs without an associated underlying risk factor like broad-spectrum antibiotic usage, immunosuppression and immunological disorders.Patients may present with oropharyngeal symptoms, odynophagia and dysphagia.Treatment is directed both at the underlying cause (which should be investigated for) and with oral antifungal agents.

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.

According to the NICE guidelines, the frequency of stool passage is considered constipation when two or more of the following findings are present: Fewer than 3 stools a week, large hard stools, stools that resemble rabbit droppings| symptoms associated with defecation including distress, bleeding or straining| a history of previous episodes of a precious/current anal fissure. The child in the scenario fails to meet the criteria, and has no evidence of impacted faeces on examination. The best course of action is to encourage the parents to give the child more water to prevent dehydration, and feed the child a fibre rich diet including fruits, vegetables and high fibre bread.

The most probable diagnosis for this patient would be Crohn’s disease.Crohn’s disease:An inflammatory bowel disease which can affect any part of the bowel from the mouth to the anus. Symptoms include abdominal pain, diarrhoea, pyrexia and weight loss. Extra-intestinal manifestations include arthritis, uveitis, fatigue, anaemia and rashes including pyoderma gangrenosum and erythema nodosum.Other options:- Anorexia nervosa is an important diagnosis to consider. There are no indicators in the description that she has a fear of gaining weight or a strong desire to be thin.- Diabetic ketoacidosis is incorrect because there is no polydipsia or polyuria. A patient in DKA is more likely to present with vomiting and not diarrhoea.- Recurrent aphthous stomatitis is not a correct answer because it does not explain all of the symptoms described, only the mouth ulcers.- Ulcerative colitis (UC) is also incorrect. UC is a form of inflammatory bowel disease that causes inflammation in the colon. The main symptom is bloody stools, which is not mentioned as a feature in history.

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.

The boy needs re-hydration and hydro-electrolytic re-balancing due to fluid losses from the gastroenteritis and subsequent dehydration.

The most probable diagnosis for this patient would be congenital hypertrophic pyloric stenosis.Congenital Hypertrophic Pyloric Stenosis (CHPS):Pyloric stenosis should be ruled out in any baby who presents with a long-term history of vomiting and failure to thrive. Infants typically present with projectile, non-bilious vomiting and are said to be hungry and wanting to feed despite poor weight gain. A blood gas would be helpful in this instance, although the diagnosis can be made more accurately by observing the stenosis during ultrasound. Many infants have symptoms of gastroesophageal reflux disease, although only a small minority are unable to gain weight adequately. A UTI in infants can present with non-specific symptoms, but they might have a fever and can show poor feeding. Malrotation will present with bilious vomiting.The definitive surgical management is the Ramsteadt’s pyloromyotomy.

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.

Celiac disease has characteristic shortened intestinal villi. When patients with celiac disease eat products containing gluten, they are unable to absorb the nutrients due to flattened or shortened intestinal villi. The blistering rash present on the patient’s elbows strongly suggests celiac disease. This rash is a sign of the condition Dermatitis Herpetiformis which is associate with celiac disease. Therefore, it is also often called ‘gluten rash’.

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.

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.

Peutz-Jeghers syndrome is an autosomal dominant genetic disease. It presents with hyperpigmentation patches on the oral mucosa, lips, palm and soles, and nasal alae. It also presents with hamartomatous polyps in the gut, hence the fresh blood in this particular case.

Anorexia nervosa is a serious, psychiatric eating disorder characterized by distorted self-image due to which abnormal eating behaviours are adopted. This disorder affects multiple bodily systems, including the gastrointestinal system. The GI manifestations of anorexia are enlarged salivary glands due to purging behaviour, gastritis, gastroparesis, acute gastric dilatation, superior mesenteric artery syndrome, elevated liver transaminases, which cause hepatocyte apoptosis leading to cirrhosis, and steatosis leading to fatty liver. Hepatosplenomegaly is not a recognized complication of anorexia nervosa.

Intussusception is an urgent condition that must be excluded first as it may lead to life-threatening complications.

The gastrocolic reflex is a physiological reflex that involves increase in colonic motility in response to stretch in the stomach and by-products of digestion in the small intestine. It is shown to be uneven in its distribution throughout the colon, with the sigmoid colon affected more than the right side of the colon in terms of a phasic response. Various neuropeptides have been proposed as mediators of this reflex, such as serotonin, neurotensin, cholecystokinin and gastrin.

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.

Jaundice in a new-born on the day of delivery is most likely due to Rh incompatibility. This occurs when the mother is Rh-negative and the baby is Rh-positive. Antibodies in the mother against the Rh factor in the baby will destroy the red blood cells in the baby, increasing the bilirubin in the blood. Breast milk jaundice and Galactosemia do not occur immediately after birth, and congenital rubella syndrome and formula feeding does not cause jaundice in babies.

Crigler-Najjar syndrome is a rare genetic disorder characterized by an inability to properly convert and clear bilirubin from the body.The hallmark finding of Crigler-Najjar syndrome is a persistent yellowing of the skin, mucous membranes and whites of the eyes (jaundice).There are two forms of this disorder: Crigler-Najjar syndrome type I, characterized by a nearly complete lack of enzyme activity and severe, even life-threatening symptoms| and Crigler-Najjar syndrome type II, characterized by partial enzyme activity and milder symptoms. Both forms are inherited as autosomal recessive traits and are caused by errors or disruptions (mutations) of the UGT1A1 gene.The symptoms of Crigler-Najjar syndrome type I become apparent shortly after birth. Affected infants develop severe, persistent yellowing of the skin, mucous membranes and whites of the eyes (jaundice). These symptoms persist after the first three weeks of life.Infants are at risk for developing kernicterus, also known as bilirubin encephalopathy, within the first month of life.Crigler-Najjar syndrome type II is a milder disorder than type I. Affected infants develop jaundice, which increases during times when an infant is sick (concurrent illness), has not eaten for an extended period (prolonged fasting) or is under general anaesthesia. Some people have not been diagnosed until they are adults. Kernicterus is rare in Crigler-Najjar syndrome type II, but can occur especially when an affected individual is sick, not eating or under anaesthesia

Bulimia nervosa is a condition in which a person is involved in binge eating and then purging. This patient has swollen parotid glands. The glands swell in order to increase saliva production so that the saliva lost in the vomiting is compensated. This patient also has thickened calluses on the back of her hand. This is known as Russell’s sign. This occurs because of putting fingers in the mouth again and again to induce the gag reflex and vomit. The knuckles get inflamed in the process after coming in contact with the teeth multiple times.

The Green Book guidelines report in an active infection (HBeAg+ and HBsAg+) to give the vaccine as well as immunoglobulin. If antibodies are present it is not active infection (anti-Hbe) and then in that case only the vaccine, and no immunoglobulin, would be given. The presence of HBeAg means a person is infectious and can transmit to other people.

Polycythaemia is a condition in which there is an increased red cell mass and increasing blood viscosity, which decreases its ability to flow. It is not associated with food allergies, but is fundamentally caused by either an overproduction of red blood cells, or a reduction in the volume of plasma. Abdominal pain, constipation, loose and frequent stools, and pallor are all non IGE mediated symptoms of food allergy according to NICE guidelines in the UK.

Biliary atresia is a rare condition that usually becomes symptomatic 2 to 8 weeks after birth. It can be congenital or acquired. Typical symptoms include jaundice, weight loss, dark urine and pale stools.

Food poisoning is defined as an illness caused by the consumption of food or water contaminated with bacteria and/or their toxins, or with parasites, viruses, or chemicals. The most common pathogens are Norovirus, Escherichia coli, Salmonella, Clostridium perfringens, Campylobacter, and Staphylococcus aureus.The following are some of the salient features of food poisoning:Acute diarrhoea in food poisoning usually lasts less than 2 weeks. Diarrhoea lasting 2-4 weeks is classified as persistent. Chronic diarrhoea is defined by duration of more than 4 weeks.The presence of fever suggests an invasive disease. However, sometimes fever and diarrhoea may result from infection outside the GI tract, as in malaria.A stool with blood or mucus indicates invasion of the intestinal or colonic mucosa.Reactive arthritis can be seen with Salmonella, Shigella, Campylobacter, and Yersinia infections.A profuse rice-water stool suggests cholera or a similar process.Abdominal pain is most severe in inflammatory processes. Painful abdominal cramps suggest underlying electrolyte loss, as in severe cholera.A history of bloating should raise the suspicion of giardiasis.Yersinia enterocolitis may mimic the symptoms of appendicitis.Proctitis syndrome, seen with shigellosis, is characterized by frequent painful bowel movements containing blood, pus, and mucus. Tenesmus and rectal discomfort are prominent features.Consumption of undercooked meat/poultry is suspicious for Salmonella, Campylobacter, Shiga toxin E coli, and C perfringens.Consumption of raw seafood is suspicious for Norwalk-like virus, Vibrioorganism, or hepatitis A.Consumption of homemade canned foods is associated with C botulinum.Consumption of unpasteurized soft cheeses is associated with Listeria, Salmonella, Campylobacter, Shiga toxin E coli, and Yersinia.Consumption of deli meats notoriously is responsible for listeriosis.Consumption of unpasteurized milk or juice is suspicious for Campylobacter, Salmonella, Shiga toxin E coli, and Yersinia.Salmonella has been associated with consumption of raw eggs.

Pellagra occurs as a result of niacin (vitamin B-3) deficiency. Niacin is required for most cellular processes. Since tryptophan in the diet can be converted to niacin in the body, both of these need to be deficient for pellagra to develop.The classical triad of symptoms is diarrhoea, dermatitis and dementia.The first sign is reddened skin with superficial scaling in areas exposed to sunlight, heat and friction. This may resemble severe sunburn then gradually subsides leaving a dusky brown-red colouration. The rash is usually symmetrical with a clear edge between affected and unaffected skin.