Acute Abdominal Pain (OSCE focused)

Candidate Instructions: You are a final year medical student. A 45-year-old patient has presented to the Emergency Department with abdominal pain. Take a focused history. At the end, summarise your findings to the examiner and outline your differential diagnoses and initial investigations. Do not perform an abdominal examination at this station.

Key Areas to Cover ✅

• 📍 Site, Onset, Character, Radiation, Associated symptoms, Timing, Exacerbating/relieving factors, Severity (SOCRATES approach).
• 🚨 Red flags: vomiting blood, melaena, jaundice, haemodynamic compromise.
• 🍽️ Gastrointestinal symptoms: nausea, vomiting, bowel habit change, rectal bleeding.
• 🧪 Urinary/reproductive: dysuria, frequency, haematuria; LMP, pregnancy status, gynaecological history in women.
• 📜 Past medical/surgical history: gallstones, peptic ulcer, pancreatitis, IBD, vascular disease, surgeries.
• 💊 Medications, allergies, alcohol, smoking, drug use.

Examiner Prompts 💬

• “How would you differentiate between surgical and medical causes of abdominal pain?”
• “What immediate bedside investigations would you request?”

Differential Diagnoses 🔎

Mark Scheme (10 points) 📝

Investigations 🔬

• Bedside: obs, urinalysis (infection, haematuria), pregnancy test in women.
• Bloods: FBC, U&E, LFT, CRP, amylase/lipase, clotting, group & save, troponin if epigastric pain.
• Imaging: abdominal US (RUQ pain), CT abdo/pelvis (suspected obstruction, perforation, AAA), CXR for free air.

Management 🩺

• Resuscitate: IV access, fluids, analgesia, antiemetics.
• Keep NBM if surgical pathology suspected.
• Surgical review if peritonitis, obstruction, AAA, appendicitis suspected.
• Medical management for non-surgical causes (e.g. gastritis, hepatitis, renal colic with analgesia and fluids).

Teaching Commentary 📚

Abdominal pain OSCEs test whether you can take a safe, structured history. Always think anatomically (quadrants) + systemically (GI, GU, gynae, vascular). Spotting red flags early and mentioning urgent imaging/fluids/surgical review will score highly. In exams, your differential breadth and safe planning matter more than nailing the “right” diagnosis.

🧑‍⚕️ Case Examples - Acute Abdominal Pain in Adults

• Case 1 (Biliary Colic → Cholecystitis): 🟢 A 45-year-old woman presents with sudden right upper quadrant pain after a fatty meal, radiating to the right shoulder. She has fever and Murphy’s sign is positive. Ultrasound shows gallstones with gallbladder wall thickening. Diagnosis: Acute cholecystitis. Teaching point: RUQ pain + fever + Murphy’s sign suggests cholecystitis; managed with IV antibiotics and cholecystectomy.
• Case 2 (Perforated Peptic Ulcer): 🌡️ A 50-year-old man with history of NSAID use presents with sudden, severe epigastric pain radiating to the back. Abdomen rigid with peritonism. Upright CXR shows free air under the diaphragm. Diagnosis: Perforated peptic ulcer. Teaching point: “Board-like” abdomen + free air = perforation; requires urgent surgery and IV antibiotics.
• Case 3 (Acute Diverticulitis): 🍽️ A 62-year-old man presents with left lower quadrant abdominal pain, fever, and altered bowel habit. Exam reveals LLQ tenderness and mild guarding. CT abdomen confirms diverticulitis. Diagnosis: Acute diverticulitis. Teaching point: LLQ pain + systemic upset in older adults suggests diverticulitis; manage with antibiotics, fluids, and surgery if perforated.
• Case 4 (Ruptured Abdominal Aortic Aneurysm): 🚨 A 70-year-old man with hypertension develops sudden severe back and abdominal pain with collapse. He is hypotensive with a pulsatile abdominal mass. Diagnosis: Ruptured AAA. Teaching point: Classic triad = pain, hypotension, pulsatile mass; requires immediate vascular surgery and resuscitation.
• Case 5 (Acute Pancreatitis): 🔥 A 40-year-old woman presents with severe epigastric pain radiating to the back, worse when lying flat and relieved by sitting forward. Amylase is 800 U/L. Diagnosis: Acute pancreatitis. Teaching point: Think pancreatitis with severe epigastric pain + raised amylase/lipase; assess severity (Glasgow score), give IV fluids, analgesia, and monitor for complications.
• Case 6 (Acute Appendicitis): 🔪 A 25-year-old man presents with abdominal pain that started centrally and migrated to the right iliac fossa over 12 hours. Exam reveals McBurney’s point tenderness with rebound. CRP and WCC are raised. Diagnosis: Acute appendicitis. Teaching point: Classic migratory pain with peritonism; requires appendicectomy. Delay risks perforation and peritonitis.
• Case 7 (Small Bowel Obstruction): 🌀 A 60-year-old woman with past hysterectomy presents with colicky abdominal pain, vomiting, and abdominal distension. On exam: high-pitched “tinkling” bowel sounds. Abdominal X-ray shows multiple fluid levels. Diagnosis: Small bowel obstruction (adhesional). Teaching point: Colicky pain + vomiting + distension + tinkling sounds = obstruction; management = NG tube, fluids, and surgery if strangulated.
• Case 8 (Mesenteric Ischaemia): ⚡ A 68-year-old man with atrial fibrillation presents with sudden severe abdominal pain out of proportion to clinical findings. Lactate is elevated. CT angiogram confirms mesenteric artery occlusion. Diagnosis: Acute mesenteric ischaemia. Teaching point: “Pain out of proportion” is the hallmark; urgent revascularisation ± bowel resection is required.