From the midgut derives most of the small intestine as well as some parts of the large intestine, including the appendix. The appendix is at the base of caecum, up to 10cm long and mainly comprised of lymphoid tissue (Hence mesenteric adenitis may mimic appendicitis).

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.

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.

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.

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.

The most common position of the appendix is the retrocecal position.Note: If a retrocecal appendix is difficult to remove, then mobilisation of the right colon significantly improves access.Other options:The various positions of the appendix are:- Retrocecal (74%)- Pelvic (21%)- Postileal- Subcaecal- Paracaecal- Preileal

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.

Based on the clinical scenario, the most probable diagnosis for this patient is pancreatitis.Although rare in childhood, the presence of abdominal pain radiating to the back with shock and tachycardia, and a raised amylase, should raise a suspicion of pancreatitis. Possible causes include trauma, drugs, viral illness, mumps, hyperparathyroidism, hyperlipidaemia and cystic fibrosis. Other options:- Normal LFTs in this patient make hepatitis unlikely. – Gastroenteritis with severe diarrhoea and vomiting may account for the shock and tachycardia, but guarding on abdominal examination and the raised amylase would not be explained by gastroenteritis. – Pregnancy is an important diagnosis to consider in an adolescent with abdominal pain, but the raised amylase and other features point to a diagnosis of pancreatitis.

Celiac disease is classified as a Type IV hypersensitivity mediated by T-cell response. Negatively charged gliadin has been shown to induce interleukin 15 in the enteric epithelial cells, stimulating the proliferation of the natural killer cells and intraepithelial lymphocytes to express NK-G2D, a marker for natural killer T lymphocytes.

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.

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.

This patient has Wilson’s disease. They Kayser-Fleischer ring (ring that encircles the iris) is diagnostic of this. Low serum copper is seen in Wilson’s disease. With the Kayser-Fleischer ring, this makes all of the other answer choices incorrect.

The coeliac axis supplies the liver and stomach and from the oesophagus to the first half of the duodenum. The second half of the duodenum to the first two thirds of the transverse colon is supplied by the superior mesenteric artery. The inferior mesenteric supplies the last third of the transverse colon (approximately from the splenic flexure) to the first third of the rectum. The last two thirds of the rectum are supplied by the middle rectal artery. The greater curvature of the stomach is supplied by branches of the splenic artery, which itself comes from the coeliac axis.

Answer: Surveillance annual flexible sigmoidoscopy from age 13 years until age 30 years. Familial adenomatous polyposis (FAP) is the most common adenomatous polyposis syndrome. It is an autosomal dominant inherited disorder characterized by the early onset of hundreds to thousands of adenomatous polyps throughout the colon. If left untreated, all patients with this syndrome will develop colon cancer by age 35-40 years. In addition, an increased risk exists for the development of other malignancies.Most patients with FAP are asymptomatic until they develop cancer. As a result, diagnosing presymptomatic patients is essential.Of patients with FAP, 75%-80% have a family history of polyps and/or colorectal cancer at age 40 years or younger.Nonspecific symptoms, such as unexplained rectal bleeding (haematochezia), diarrhoea, or abdominal pain, in young patients may be suggestive of FAP.In a minority of FAP families a mutation cannot be identified and so annual flexible sigmoidoscopy should be offered to at risk family members from age 13–15 years until age 30, and at three to five year intervals thereafter until age 60 years.

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’.

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.

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.

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.

Gastroesophageal reflux occurs in almost all infants, manifesting as wet burps after feeding. The spit-ups appear effortless and not particularly forceful.Infants in whom reflux has caused GERD have additional symptoms, such as irritability, feeding refusal, and/or respiratory symptoms such as chronic recurrent coughing or wheezing and sometimes stridor. Much less commonly, infants have intermittent apnoea or episodes of arching the back and turning the head to one side (Sandifer syndrome). Infants may fail to gain weight appropriately or, less often, lose weight.Incidence of gastroesophageal reflux increases between 2 months and 6 months of age (likely due to an increased volume of liquid at each feeding) and then starts to decrease after 7 months. Gastroesophageal reflux resolves in about 85% of infants by 12 months and in 95% by 18 months.

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.

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.

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.

Breast feeding should be continued for babies with breast milk jaundice as this is a benign condition.

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 prompt is suggestive of acute appendicitis. The Alvarado score is a clinical scoring system used to determine the likelihood of appendicitis, so this is the correct answer. A score greater than 6 is generally considered at risk for having acute appendicitis. It has 8 different criteria included (symptoms, signs, and lab results) and divides patients into appendicitis unlikely, possible, probable, and definite. The Center Score is a score to access the likelihood that pharyngitis is due to Strep. The Child-Pugh score predicts prognosis in liver cirrhosis. The Glasgow score is two different scores– the Glasgow coma score in trauma, which estimates level of consciousness, essentially, and The Glasgow Imrie Criteria which determines the severity of acute pancreatitis based on 8 lab values. The MELD score predicts the severity of end-stage liver disease.

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.

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.

Frequent regurgitation of milk and microcytic anaemia is suggestive of a hiatus hernia. The reflux causes regurgitation of milk and frequent ulceration of the lower oesophageal mucosa potentially resulting in blood loss and anaemia. Duodenal atresia usually presents with bilious vomiting and pyloric stenosis presents with projectile vomiting. Alpha 1 antitrypsin deficiency and cystic fibrosis usually do not present with vomiting.

The main problem with infants having gastroenteritis is dehydration. So they should be admitted to the hospital for IV fluids if they are not tolerating oral fluids.

The most likely causative organism for the symptoms of this child is Giardia lamblia.Giardiasis results in fat malabsorption thus giving rise to greasy stools. It is resistant to chlorination, hence has a risk of transfer in swimming pools.World Health Organisation definitions- Diarrhoea: > 3 loose or watery stool per day- Acute diarrhoea < 14 days- Chronic diarrhoea > 14 daysConditions that usually present as acute diarrhoea:- Gastroenteritis: It may be accompanied by abdominal pain or nausea/vomiting.- Antibiotic therapy: Can occur following antibiotic therapy, especially common with broad spectrum antibiotics.Conditions that usually present as chronic diarrhoea:- Irritable bowel syndrome: It is a very common disease.The most consistent features are abdominal pain, bloating and change in bowel habit. Patients may be divided into those with diarrhoea predominant IBS and those with constipation-predominant IBS.Features such as lethargy, nausea, backache and bladder symptoms may also be present in these patients.- Ulcerative colitis: It presents as bloody diarrhoea. Patients can also present with crampy abdominal pain and weight loss. Faecal urgency and tenesmus may be seen.- Crohn’s disease: It is also associated with crampy abdominal pains and diarrhoea. Bloody diarrhoea less common than in ulcerative colitis. Other features include malabsorption, mouth ulcers perianal disease and intestinal obstruction – Colorectal cancer: It is very rare in children. The symptoms depend on the site of the lesion but include diarrhoea, rectal bleeding, anaemia and constitutional symptoms like weight loss and anorexia.- Coeliac disease: In children, it may present with failure to thrive, diarrhoea and abdominal distension.Other conditions associated with diarrhoea include thyrotoxicosis, laxative abuse, appendicitis, and radiation enteritis.