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

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.

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.

Laxatives have been shown to be beneficial in the treatment of chronic childhood constipation. Studies have shown that polyethylene glycol, mineral oil, magnesium hydroxide, and lactulose are effective and can be used for a prolonged periods without risk.

Pale stools suggest obstructive jaundice. Initially, the symptoms of biliary atresia are indistinguishable from those of neonatal jaundice, a usually harmless condition commonly seen in infants. However, infants with biliary atresia develop progressive conjugated jaundice, pale white stools and dark urine.

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 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.

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

The structure in question is the rectus sheath. This sheath encloses the rectus abdominis muscle and thus, will be encountered by the surgeon.Note:- Midline incision: It is the most common approach to the abdomen. The structures divided during this incision are linea alba, transversalis fascia, extraperitoneal fat, and peritoneum ( with care taken to avoid the falciform ligament above the umbilicus).The bladder can be accessed via an extraperitoneal approach through the space of Retzius.- Paramedian incision: It is an incision that is made parallel to the midline. The structures divided or retracted are anterior rectus sheath, rectus (retracted), posterior rectus sheath, transversalis fascia, extraperitoneal fat, and peritoneum.- Battle incision: It is similar to a paramedian but the rectus is displaced medially (and thus denervated).- Kocher’s incision: It is an incision made under the right subcostal margin, e.g. cholecystectomy (open).- Lanz incision: It is an incision in the right iliac fossa, e.g. appendicectomy.Gridiron incision: It is an oblique incision centred over the McBurney’s point – usually used for appendicectomy (less cosmetically acceptable than LanzPfannenstiel’s incision: It is a transverse suprapubic incision, primarily used to access pelvic organs.McEvedy’s incision: It is a groin incision used for emergency repair strangulated femoral hernia.Rutherford Morrison incision: It provides an extraperitoneal approach to left or right lower quadrants. It provides excellent access to iliac vessels and is the approach of choice for first-time renal transplantation.

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

Intussusception is the most suggested case here based on the child’s symptoms. The urgent course of treatment is to bring the child to a paediatric surgical unit. If air reduction attempts fail, surgery will have to be done. Risk factors for intussusception include viral infection and intestinal lymphadenopathy.

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.

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.

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.

People with Gilbert syndrome have a build-up of unconjugated bilirubin in their blood (unconjugated hyperbilirubinemia). In affected individuals, bilirubin levels fluctuate and very rarely increase to levels that cause jaundice. Gilbert syndrome is usually recognized in adolescence. If people with this condition have episodes of hyperbilirubinemia, these episodes are generally mild and typically occur when the body is under stress, for instance because of dehydration, prolonged periods without food (fasting), illness, vigorous exercise, or menstruation. Some people with Gilbert syndrome also experience abdominal discomfort or tiredness. However, approximately 30 percent of people with Gilbert syndrome have no signs or symptoms of the condition and are discovered only when routine blood tests reveal elevated unconjugated bilirubin levels.

The most common cause for acute bloody diarrhoea in a 10-year-old child is Campylobacter.Note:Campylobacter is the most common bacterial cause of gastroenteritis in the UK. It typically presents with bloody diarrhoea, fever, abdominal pain and vomiting. The primary source of Campylobacter is uncooked poultry. Treatment is generally supportive unless the child is immunosuppressed or the symptoms are persistent.Other options:- E. coli 0157:H7: It causes acute haemorrhagic diarrhoea, usually afebrile. It can lead to haemolytic uremic syndrome (haemolytic anaemia, acute renal failure and thrombocytopenia), which is the commonest cause of acute renal failure in children.- Rotavirus: It rarely causes bloody diarrhoea.- Salmonella and Yersinia: While they can cause bloody diarrhoea, they are much less common compared to Campylobacter.

Based on the history and clinical presentation, she most likely has iron toxicity.Iron can cause scarring of the gut mucosa. This explains her pyloric stenosis. This typically occurs at the pylorus as this is where iron tablets tend to pool and cause maximal tissue damage.Other options:- Citalopram: Selective serotonin reuptake inhibitors (SSRIs) ingestion rarely causes serious consequences. It can rarely lead to serotonin syndrome (autonomic instability, mental status change, and increased neuromuscular tone).- Ibuprofen: While it may cause gastritis, ibuprofen does not cause pyloric/intestinal stenosis.- Thyroxine: An overdose of thyroxine will cause features of hyperthyroidism which are not present in the patient in question.- Zinc: High doses of zinc can cause abdominal cramps, nausea, vomiting and diarrhoea.

Total parenteral nutrition (TPN) frequently causes derangement of liver function in children. Other options:- While line sepsis and thromboembolism are recognised complications of TPN, they do not occur frequently. – A child who is on TPN will require regular blood tests because of the potential for the development of electrolyte abnormalities. Need to observe their liver function, in order to provide TPN more accurately.

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.

The signs and symptoms of vitamin D-dependent rickets begin within months after birth, and most are the same for all types of the condition. The weak bones often cause bone pain and delayed growth and have a tendency to fracture. When affected children begin to walk, they may develop abnormally curved (bowed) legs because the bones are too weak to bear weight. Impaired bone development also results in widening of the metaphysis, especially in the knees, wrists, and ribs. Some people with vitamin D-dependent rickets have dental abnormalities such as thin tooth enamel and frequent cavities. Poor muscle tone (hypotonia) and muscle weakness are also common in this condition, and some affected individuals develop seizures.