Question 1: Hypertrophic Pyloric Stenosis (HPS)
Stem: A 4-week-old boy presents with a 1-week history of non-bilious, projectile vomiting immediately after feeds. He is clinically dehydrated. An abdominal ultrasound is performed.
Question: Which of the following measurements is the most widely accepted primary diagnostic criterion for HPS?
(A) Pyloric muscle thickness > 3 mm (B) Pyloric channel length < 10 mm (C) Pyloric muscle thickness < 2 mm (D) Total pyloric diameter > 20 mm (E) Gastric peristaltic waves > 10 per minute
Correct Answer: (A) Pyloric muscle thickness > 3 mm.
Explanation:
- Why (A) is correct: The single most specific and widely used measurement for diagnosing HPS is the pyloric muscle thickness, which is abnormal if it is greater than 3 mm. A pyloric channel length > 16 mm is also used, but muscle thickness is the primary criterion.
- Why (B) is wrong: The pyloric channel is elongated in HPS, so a measurement would be > 16 mm. A length < 10 mm would be normal.
- Why (C) is wrong: A muscle thickness < 2 mm is normal.
- Why (D) is wrong: Total pyloric diameter is a less reliable sign and can be affected by the degree of gastric distension.
- Why (E) is wrong: Hyper-peristalsis (“caterpillar sign”) is a finding in HPS, but it is not a diagnostic measurement.
Key Points: Hypertrophic Pyloric Stenosis (HPS) 🍼
- Clinical: Projectile, non-bilious vomiting in a neonate (2-8 weeks). Palpable “olive” mass in the epigastrium.
- Imaging: Ultrasound is the modality of choice.
- Diagnostic Criteria:
- Pyloric muscle thickness > 3 mm (most specific).
- Pyloric channel length > 16 mm.
- Other Signs: “Antral nipple sign” (prolapsing mucosa), “caterpillar sign” (hyper-peristalsis).
Question 2: Malrotation with Midgut Volvulus
Stem: A 3-day-old neonate presents with sudden-onset, bilious vomiting and abdominal distension. An urgent upper GI contrast study is performed. It demonstrates that the duodeno-jejunal (DJ) flexure is low-lying and to the right of the midline, and the duodenum and proximal jejunum have a “corkscrew” appearance.
Question: What is the most likely diagnosis?
(A) Duodenal Atresia (B) Malrotation with Midgut Volvulus (C) Jejunal Atresia (D) Hypertrophic Pyloric Stenosis (E) Hirschsprung’s Disease
Correct Answer: (B) Malrotation with Midgut Volvulus.
Explanation:
- Why (B) is correct: Bilious vomiting in a neonate is a surgical emergency until proven otherwise. The “corkscrew” appearance of the duodenum/jejunum on an upper GI study is the pathognomonic sign of a midgut volvulus, which is a life-threatening complication of underlying malrotation. The abnormal (low and right) position of the DJ flexure confirms the malrotation.
- Why (A) is wrong: Duodenal atresia presents with bilious vomiting but shows a “double bubble” sign with no contrast passing the proximal duodenum.
- Why (C) is wrong: Jejunal atresia presents as a “triple bubble” sign or multiple dilated loops proximal to the atresia.
- Why (D) is wrong: HPS causes non-bilious vomiting.
- Why (E) is wrong: Hirschsprung’s is a distal large bowel obstruction.
Key Points: Malrotation with Volvulus 🌀
- Clinical: Bilious vomiting in a neonate. A true surgical emergency.
- Imaging:
- Ultrasound: “Whirlpool sign” (SMV and SMA twisted in the mesentery). In malrotation, the SMV is abnormally located to the left of the SMA (it should be on the right).
- Upper GI Contrast: “Corkscrew” sign (pathognomonic for volvulus). Abnormal DJ flexure (not at the level of L1, to the left of the pedicle).
Question 3: Duodenal Atresia
Stem: A 1-day-old infant with Down Syndrome (Trisomy 21) presents with bilious vomiting. An abdominal radiograph is performed, which shows a large, gas-filled stomach and a second, smaller, gas-filled proximal duodenum. There is no gas in the bowel distal to this.
Question: This radiographic finding is known as the:
(A) “Single bubble” sign (B) “Double bubble” sign (C) “Triple bubble” sign (D) “Coffee bean” sign (E) “Sentinel loop” sign
Correct Answer: (B) “Double bubble” sign.
Explanation:
- Why (B) is correct: The “double bubble” sign (gas in the stomach + gas in the proximal duodenum) combined with no distal gas is the classic plain film finding for duodenal atresia.
- Why (A) is wrong: The “single bubble” sign is seen in pyloric stenosis (a distended stomach with no distal gas).
- Why (C) is wrong: The “triple bubble” sign (stomach + duodenum + jejunum) is seen in jejunal atresia.
- Why (D) is wrong: The “coffee bean” sign is a finding of sigmoid volvulus in an adult.
- Why (E) is wrong: A “sentinel loop” is a non-specific sign of focal ileus.
Key Points: Duodenal Atresia
- Pathology: Congenital failure of recanalization of the duodenal lumen.
- Clinical: Bilious vomiting.
- Association: Strongly associated with Down Syndrome (Trisomy 21) (approx. 30% of cases).
- X-ray: “Double bubble” sign. The absence of distal gas confirms complete atresia. (If gas is present distally, it implies an incomplete duodenal web or stenosis).
Question 4: Necrotizing Enterocolitis (NEC)
Stem: A 3-week-old premature neonate (born at 28 weeks) develops a distended, tender abdomen and bloody stools. A supine abdominal X-ray is performed.
Question: Which of the following findings is the most specific pathognomonic sign for necrotizing enterocolitis (NEC)?
(A) Portal venous gas (B) Pneumatosis intestinalis (C) Pneumoperitoneum (D) Diffuse, dilated bowel loops (E) Rigler’s sign
Correct Answer: (B) Pneumatosis intestinalis.
Explanation:
- Why (B) is correct: Pneumatosis intestinalis (gas within the bowel wall) is the pathognomonic sign of NEC. It appears as linear or bubbly lucencies within the wall of the affected bowel.
- Why (A) is wrong: Portal venous gas (air in the portal system) is a complication of NEC. It is a grave prognostic sign but is not the primary diagnostic finding (it can also be caused by other things, like bowel ischaemia).
- Why (C) is wrong: Pneumoperitoneum (free air) indicates perforation, which is the most severe complication of NEC (Bell’s Stage III), but it is not the diagnostic sign of NEC itself.
- Why (D) is wrong: Dilated loops are a non-specific sign of ileus.
- Why (E) is wrong: Rigler’s sign (air on both sides of the bowel wall) is a sign of pneumoperitoneum, not pneumatosis.
Key Points: Necrotizing Enterocolitis (NEC)
- Definition: Ischaemic necrosis of the bowel in a neonate.
- Risk Factors: Prematurity is the single biggest risk factor.
- Pathognomonic Sign (X-ray): Pneumatosis intestinalis (intramural gas).
- Signs of Complication:
- Portal venous gas (indicates severe disease/necrosis).
- Pneumoperitoneum (indicates perforation = surgical emergency).
Question 5: Intussusception
Stem: A 2-year-old boy presents with a 1-day history of intermittent, severe, colicky abdominal pain and vomiting. His mother reports a “redcurrant jelly” stool. An ultrasound of the right lower quadrant is performed.
Question: What is the classic diagnostic finding on this ultrasound?
(A) An enlarged, hyperaemic appendix (> 6 mm) (B) A “target” or “doughnut” sign (C) A “corkscrew” sign of the duodenum (D) A “double bubble” sign (E) A “whirlpool” sign of the SMA/SMV
Correct Answer: (B) A “target” or “doughnut” sign.
Explanation:
- Why (B) is correct: This is the classic ultrasound appearance of an intussusception (telescoping of bowel into itself). On a transverse view, the layers of bowel-in-bowel create a “target” or “doughnut” sign. On a longitudinal view, it is called the “pseudokidney” sign.
- Why (A) is wrong: This describes appendicitis.
- Why (C) is wrong: This is the sign of midgut volvulus on a contrast study.
- Why (D) is wrong: This is the sign of duodenal atresia on an X-ray.
- Why (E) is wrong: This is the sign of midgut volvulus on ultrasound.
Key Points: Intussusception
- Definition: Telescoping of one bowel segment (intussusceptum) into another (intussuscipiens).
- Classic Age: 6 months to 3 years.
- Clinical Triad: Colicky pain, “redcurrant jelly” stool (late sign), palpable “sausage-shaped” mass.
- Imaging:Ultrasound is the modality of choice.
- “Target” / “Doughnut” sign (transverse).
- “Pseudokidney” sign (longitudinal).
- Treatment: Air or contrast enema is both diagnostic and therapeutic (hydrostatic reduction).
Question 6: Wilms’ Tumour (Nephroblastoma)
Stem: A 3-year-old child presents with a large, palpable, non-tender abdominal mass. A contrast-enhanced CT scan reveals a large, heterogeneous, solid-and-cystic mass arising from the right kidney. The mass distorts the collecting system, and a rim of normal, stretched renal parenchyma is seen around it.
Question: The presence of a rim of normal renal tissue (“claw sign”) confirms an intra-renal origin and is most characteristic of:
(A) Wilms’ Tumour (B) Neuroblastoma (C) Hepatoblastoma (D) Multicystic Dysplastic Kidney (MCDK) (E) Angiomyolipoma
Correct Answer: (A) Wilms’ Tumour.
Explanation:
- Why (A) is correct: A Wilms’ tumour is the most common paediatric renal malignancy. The “claw sign” (a sharp, beak-like claw of normal renal tissue surrounding the mass) is the key finding that proves a mass is intra-renal in origin, which is characteristic of Wilms’.
- Why (B) is wrong: A neuroblastoma is an extra-renal mass (arising from the adrenal gland/sympathetic chain) that displaces or encases the kidney, but it does not have a renal “claw sign.”
- Why (C) is wrong: A hepatoblastoma is a tumour of the liver.
- Why (D) is wrong: MCDK is a non-functioning, congenital kidney replaced by non-communicating cysts, not a solid tumour.
- Why (E) is wrong: Angiomyolipoma is rare in children (unless they have Tuberous Sclerosis) and is diagnosed by the presence of fat.
Key Points: Wilms’ Tumour (Nephroblastoma) Nephroblastoma
- Most common renal tumour in children (peak 3-4 years).
- Imaging:
- Large, well-defined, heterogeneous mass within the kidney.
- “Claw Sign” confirms intra-renal origin.
- Tends to invade the renal vein and IVC.
- Associations: Beckwith-Wiedemann, WAGR (Wilms’, Aniridia, Genitourinary, Retardation), Denys-Drash.
- Metastasis: Most common site is the lungs.
Question 7: Neuroblastoma
Stem: A 2-year-old girl presents with a palpable abdominal mass, proptosis, and bone pain. A CT scan reveals a large, ill-defined mass in the left suprarenal region that contains punctate calcifications. The mass is seen to cross the midline and encase the aorta and SMA. The left kidney is displaced inferiorly.
Question: This combination of findings is classic for:
(A) Wilms’ Tumour (B) Neuroblastoma (C) Hepatoblastoma (D) Teratoma (E) Phaeochromocytoma
Correct Answer: (B) Neuroblastoma.
Explanation:
- Why (B) is correct: This is the classic description of a neuroblastoma. The key differentiating features from a Wilms’ tumour are: 1) Suprarenal/Paraspinal origin (extra-renal), 2) Calcifications (common in neuroblastoma, rare in Wilms’), and 3) Tendency to encase vessels and cross the midline. The proptosis (orbital metastases) is also a classic finding.
- Why (A) is wrong: Wilms’ tumour is intra-renal (“claw sign”) and rarely calcifies. It tends to displace vessels, not encase them.
- Why (C) is wrong: Hepatoblastoma is an intra-hepatic mass.
- Why (D) is wrong: A teratoma is a germ cell tumour that often contains fat, fluid, and well-formed bone/teeth.
- Why (E) is wrong: Phaeochromocytoma is very rare in children and is a functional tumour.
Key Points: Neuroblastoma
- Most common extra-cranial solid tumour in children (peak < 2 years).
- Origin: Adrenal medulla or sympathetic chain (can be anywhere from neck to pelvis).
- Imaging:
- Extra-renal mass (displaces kidney, no “claw sign”).
- Calcifications are common (~85%).
- Crosses the midline and encases vessels.
- Metastasis: Bone, bone marrow, liver, and orbits (“raccoon eyes”).
Question 8: Hepatoblastoma
Stem: A 1-year-old boy is brought in for abdominal swelling. Labs are drawn, showing a serum Alpha-fetoprotein (AFP) level of 500,000 ng/mL. A CT scan confirms a large, solitary, solid mass in the right lobe of the liver, which is enhancing heterogeneously.
Question: The combination of a liver mass in an infant and a markedly elevated AFP is most diagnostic of:
(A) Wilms’ Tumour (B) Neuroblastoma (C) Hepatoblastoma (D) Infantile Haemangioma **(E) ** Hepatic Abscess
Correct Answer: (C) Hepatoblastoma.
Explanation:
- Why (C) is correct: Hepatoblastoma is the most common primary liver tumour in children (usually < 3 years old). The key diagnostic clue is a markedly elevated serum AFP, which is seen in >90% of cases.
- Why (A) is wrong: Wilms’ tumour is a renal mass.
- Why (B) is wrong: Neuroblastoma is an adrenal/paraspinal mass.
- Why (D) is wrong: Infantile haemangioma (haemangioendothelioma) is the most common benign liver tumour in infants. It can raise AFP slightly, but not usually to this level, and it has a very specific imaging pattern (multiple, high-flow lesions).
- Why (E) is wrong: An abscess is an infectious collection, not a tumour, and would present with fever.
Key Points: Hepatoblastoma
- Most common primary paediatric liver tumour (peak age 1-3 years).
- Key Marker: Markedly elevated serum AFP (>90% of cases).
- Imaging: Typically a large, solitary, well-defined solid mass. May contain calcifications.
- Associations: Beckwith-Wiedemann syndrome, FAP, prematurity.
Question 9: Hirschsprung’s Disease
Stem: A 5-day-old neonate has failed to pass meconium and has progressive abdominal distension. A contrast enema is performed, which demonstrates a narrowed rectosigmoid segment with an abrupt calibre change to a dilated proximal colon.
Question: This “transition zone” is the hallmark of:
(A) Hirschsprung’s Disease (B) Meconium Ileus (C) Duodenal Atresia (D) Malrotation (E) Necrotizing Enterocolitis
Correct Answer: (A) Hirschsprung’s Disease.
Explanation:
- Why (A) is correct: Hirschsprung’s disease is a functional obstruction caused by an aganglionic (no nerve cells) segment of the distal colon. This aganglionic segment is spastic and narrowed. The proximal, normally-innervated colon becomes dilated from the obstruction. The point where these two segments meet is the “transition zone”, which is the key finding on a contrast enema.
- Why (B) is wrong: Meconium ileus is an obstruction of the ileum. The contrast enema would show a microcolon (a universally small, unused colon).
- Why (C) & (D) are wrong: These are proximal small bowel obstructions.
- Why (E) is wrong: NEC is necrosis of the bowel wall, not a congenital obstruction.
Key Points: Hirschsprung’s Disease
- Pathology: Congenital absence of ganglion cells (Meissner’s/Auerbach’s plexuses).
- Clinical: Failure to pass meconium, chronic constipation, distension.
- Imaging (Contrast Enema):
- “Transition Zone”: Abrupt calibre change from a narrowed, aganglionic distal segment to a dilated, normal proximal segment.
- Rectosigmoid Ratio < 1 (rectum is narrower than sigmoid).
Question 10: Meconium Ileus
Stem: A 1-day-old infant presents with abdominal distension and failure to pass meconium. An abdominal X-ray shows dilated small bowel loops and a “soap-bubble” or “bubbly” lucency in the right lower quadrant. A contrast enema reveals a universally small-calibre, unused colon.
Question: This combination of findings is highly suggestive of:
(A) Meconium Ileus (B) Hirschsprung’s Disease (C) Ileal Atresia (D) Malrotation (E) Necrotizing Enterocolitis
Correct Answer: (A) Meconium Ileus.
Explanation:
- Why (A) is correct: This is the classic picture. The “soap-bubble” appearance on X-ray is the inspissated (thick) meconium mixed with gas in the distal ileum. The contrast enema shows a “microcolon” because the colon is normal but has never been used (as the obstruction is proximal to it). Meconium ileus is pathognomonic for cystic fibrosis.
- Why (B) is wrong: Hirschsprung’s disease shows a transition zone in the colon, not a uniform microcolon.
- Why (C) is wrong: Ileal atresia would also show a microcolon, but the X-ray would show dilated loops and no “soap-bubble” sign (as the meconium is not the problem).
- Why (D) is wrong: Malrotation is a rotational anomaly, not an obstruction by meconium.
- Why (E) is wrong: NEC presents later in premature infants and shows pneumatosis.
Key Points: Meconium Ileus
- Pathology: Small bowel obstruction by thick, inspissated meconium.
- Association: Pathognomonic for Cystic Fibrosis (CF).
- Imaging:
- X-ray: Dilated small bowel, “soap-bubble” lucencies in RLQ.
- Contrast Enema: “Microcolon” (unused). Contrast may enter the ileum and show the meconium filling defects.
Question 11: Paediatric Appendicitis
Stem: An 8-year-old boy presents with a 2-day history of right iliac fossa (RIF) pain, fever, and vomiting. An ultrasound is performed, which shows a 1.2 cm, blind-ending, tubular structure in the RIF. The structure is non-compressible and demonstrates a calcified appendicolith with posterior acoustic shadowing.
Question: What is the most likely diagnosis?
(A) Appendicitis (B) Mesenteric Adenitis (C) Intussusception (D) Crohn’s Disease (E) Meckel’s Diverticulitis
Correct Answer: (A) Appendicitis.
Explanation:
- Why (A) is correct: Ultrasound is the first-line imaging modality for suspected appendicitis in children (to avoid radiation). The key findings are a dilated (> 6 mm), non-compressible, blind-ending tubular structure. The presence of an appendicolith is highly specific and increases the risk of perforation.
- Why (B) is wrong: Mesenteric adenitis (enlarged lymph nodes) is a common differential, but the appendix itself would be normal (< 6 mm and compressible).
- Why (C) is wrong: Intussusception has a “target sign” and is a different clinical picture.
- Why (D) is wrong: Crohn’s disease would show thickened, hyperaemic bowel (usually the terminal ileum), not a dilated appendix.
- Why (E) is wrong: Meckel’s diverticulitis mimics appendicitis but is much rarer; the inflamed appendix is the primary finding.
Key Points: Paediatric Appendicitis
- Most common acute surgical emergency in children.
- Imaging: Ultrasound is first-line in children.
- Ultrasound Criteria:
- Non-compressible, blind-ending tube > 6 mm in diameter.
- “Target” sign in transverse view.
- Appendicolith (highly specific).
- Periappendiceal fat stranding and hyperaemia.
Question 12: Jejunal Atresia
Stem: A 1-day-old neonate presents with bilious vomiting. An abdominal X-ray is performed, which shows a large gas bubble in the stomach, a second large bubble in the duodenum, and a third bubble in the proximal jejunum. There is no distal gas.
Question: This radiographic finding is known as the:
(A) “Single bubble” sign (B) “Double bubble” sign (C) “Triple bubble” sign (D) “Pneumatosis” (E) “Microcolon”
Correct Answer: (C) “Triple bubble” sign.
Explanation:
- Why (C) is correct: The “triple bubble” sign (gas in the stomach, duodenum, and proximal jejunum) is the classic plain film finding for jejunal atresia.
- Why (A) is wrong: “Single bubble” is for pyloric stenosis.
- Why (B) is wrong: “Double bubble” is for duodenal atresia.
- Why (D) is wrong: Pneumatosis is air in the bowel wall (NEC).
- Why (E) is wrong: Microcolon is a finding on a contrast enema, not a plain film.
Key Points: Jejunal & Ileal Atresia
- Pathology: Congenital obstruction of the jejunum or ileum.
- Cause: Thought to be from an in-utero vascular insult/ischaemia (unlike duodenal atresia, which is a failure of recanalization).
- X-ray: Multiple dilated loops of bowel proximal to the atresia.
- “Triple bubble” sign is classic for proximal jejunal atresia.
Question 13: Biliary Atresia
Stem: A 6-week-old infant presents with persistent conjugated hyperbilirubinaemia, pale stools, and dark urine. An abdominal ultrasound is performed, which shows a small or absent gallbladder. A key specific finding is an echogenic, fibrotic, triangular structure measuring 5 mm, located just anterior to the portal vein bifurcation.
Question: This specific echogenic structure is known as the:
(A) “Triangular Cord” sign (B) “Central Dot” sign (C) “Pseudokidney” sign (D) “Double Duct” sign (E) “Whirlpool” sign
Correct Answer: (A) “Triangular Cord” sign.
Explanation:
- Why (A) is correct: The “triangular cord” sign is a highly specific ultrasound finding for biliary atresia. It represents the echogenic, fibrotic remnant of the extrahepatic biliary tree (common hepatic duct) at the porta hepatis.
- Why (B) is wrong: The “central dot” sign is for Caroli’s disease.
- Why (C) is wrong: The “pseudokidney” sign is for intussusception.
- Why (D) is wrong: The “double duct” sign is for a pancreatic head mass in an adult.
- Why (E) is wrong: The “whirlpool” sign is for midgut volvulus.
Key Points: Biliary Atresia
- Definition: A neonatal emergency; progressive fibrosis and obliteration of the extrahepatic bile ducts.
- Clinical: Persistent jaundice (> 2 weeks), pale stools, dark urine.
- Ultrasound:
- “Triangular Cord” sign (specific, but operator-dependent).
- Absent or small gallbladder (or one that does not contract post-feed).
- HIDA Scan: Confirmatory test. Shows normal liver uptake but no excretion of tracer into the small bowel, even on delayed images.
Question 14: Choledochal Cyst
Stem: A 5-year-old girl presents with recurrent abdominal pain and mild jaundice. An ultrasound demonstrates a 3 cm, fusiform, cystic dilatation of the common bile duct, separate from the gallbladder.
Question: This finding is most consistent with which Todani classification of choledochal cyst?
(A) Type I (B) Type II (C) Type III (D) Type IVa (E) Type V (Caroli’s Disease)
Correct Answer: (A) Type I.
Explanation:
- Why (A) is correct: Todani Type I is the most common type of choledochal cyst (~80-90%). It is defined as a fusiform or saccular dilatation of the extrahepatic biliary tree (i.e., the common bile duct).
- Why (B) is wrong: Type II is a true diverticulum (outpouching) from the side of the CBD.
- Why (C) is wrong: Type III (a choledochocele) is a cyst of the intraduodenal portion of the CBD.
- Why (D) is wrong: Type IVa involves both intra- and extrahepatic duct dilatation.
- Why (E) is wrong: Type V (Caroli’s disease) involves intrahepatic cystic ductal dilatation only.
Key Points: Choledochal Cyst
- Definition: Congenital cystic dilatation of the biliary tree.
- Clinical: Classic triad (pain, jaundice, mass) is rare. Often presents with pancreatitis or recurrent pain.
- Classification (Todani):
- Type I: Most common. Fusiform dilatation of the extrahepatic CBD.
- Type II: Diverticulum of the CBD.
- Type III: Choledochocele (intraduodenal).
- Type IVa: Both intra- and extrahepatic dilatation.
- Type V (Caroli’s): Intrahepatic cystic dilatation only.
- Complication: High risk of cholangitis, pancreatitis, and cholangiocarcinoma.
Question 15: Henoch-Schönlein Purpura (HSP)
Stem: A 7-year-old boy presents with a palpable, purpuric rash on his buttocks and lower legs, polyarthralgia, and severe, colicky abdominal pain. An ultrasound is performed to evaluate the abdominal pain, which reveals a long segment of ileo-ileal intussusception.
Question: This presentation is most characteristic of:
(A) Henoch-Schönlein Purpura (HSP) (B) Idiopathic Ileocolic Intussusception (C) Peutz-Jeghers Syndrome (D) Appendicitis (E) Lymphoma
Correct Answer: (A) Henoch-Schönlein Purpura (HSP).
Explanation:
- Why (A) is correct: HSP is a small-vessel vasculitis. The classic tetrad is purpuric rash, arthralgia, abdominal pain, and renal involvement. The abdominal pain is due to vasculitis of the bowel wall, which can cause oedema, haemorrhage, and, critically, can act as a lead point for intussusception.
- Why (B) is wrong: Idiopathic intussusception is typically ileocolic (not ileo-ileal) and is not associated with a systemic purpuric rash.
- Why (C) is wrong: Peutz-Jeghers syndrome causes intussusception from polyps (lead points) but is associated with melanotic macules (freckles), not a purpuric rash.
- Why (D) is wrong: Appendicitis does not cause a rash or intussusception.
- Why (E) is wrong: Lymphoma can be a lead point for intussusception, but it is not associated with a purpuric rash.
Key Points: Henoch-Schönlein Purpura (HSP)
- Definition: An IgA-mediated, systemic, small-vessel vasculitis.
- Clinical: Palpable purpura (legs/buttocks), arthralgia, abdominal pain, haematuria (nephritis).
- GI Complications (from vasculitis):
- Bowel wall thickening (oedema/haemorrhage).
- GI bleeding.
- Intussusception (classically ileo-ileal or jejuno-jejunal).
