Assessment of the causes of Chronic Abdominal Pain
🩺 Chronic abdominal pain is defined as pain persisting for ≥3 months and represents a diagnostic challenge, balancing the need to identify serious organic disease while avoiding unnecessary investigations.
The key clinical skill is to distinguish functional pain (e.g. IBS) from inflammatory, structural, metabolic, or malignant causes, using a careful history to guide targeted testing.
📝 Clinical History – Structured Assessment
- ⏳ Onset & Duration
- When did the pain begin?
- Has it been present for ≥3 months?
- Continuous vs episodic?
- 📍 Location & Radiation
- Epigastric (PUD, pancreatitis)
- Periumbilical (IBS, early appendiceal pathology)
- Lower abdomen (IBD, gynaecological causes)
- Radiation to back (pancreas) or groin (renal)
- 🔥 Character of Pain
- Dull/aching (IBS, malignancy)
- Crampy/colicky (bowel, biliary)
- Burning (GERD)
- Constant vs intermittent
- 🍽️ Aggravating & Relieving Factors
- Meals (GERD, gallbladder disease)
- Specific foods (IBS, coeliac disease)
- Stress (functional disorders)
- Relief with defecation (IBS)
- 🚨 Associated Symptoms (Red Flag Screen)
- ⚖️ Unintentional weight loss
- 🤢 Persistent vomiting
- 💩 Change in bowel habit or blood in stool
- 🌡️ Fever, night sweats
- 🟡 Jaundice
- 🚻 Urinary symptoms
- 🩸 Dysmenorrhoea or dyspareunia
- 🧬 Past Medical & Surgical History
- Previous abdominal surgery (adhesions)
- Known GI disease (IBD, GERD, IBS)
- Chronic illness (diabetes, liver disease)
- 👪 Family History
- IBD, coeliac disease, colorectal cancer
- 💊 Medication History
- NSAIDs (ulcer disease)
- Opioids (constipation)
- Antibiotics (C. difficile)
🩺 Physical Examination
- 👀 General Inspection
- Pallor (anaemia)
- Jaundice
- Weight loss or cachexia
- 📊 Observations
- Fever (infection, inflammation)
- Tachycardia or hypotension
- 🫃 Abdominal Examination
- Inspection: distension, scars, visible peristalsis
- Palpation: tenderness, masses, organomegaly
- Percussion: hepatosplenomegaly, ascites
- Auscultation: altered bowel sounds
- 🩸 Rectal Examination
- Change in bowel habit, PR bleeding, anaemia
- ♀️ Pelvic Examination (where appropriate)
- Lower abdominal or cyclical pain
🔎 Investigations (Guided by Red Flags)
- 🧪 Blood Tests
- CBC – anaemia, infection
- CRP / ESR – inflammation (IBD)
- LFTs – hepatobiliary disease
- U&Es – dehydration, renal disease
- Amylase/lipase – pancreatitis
- Coeliac serology (tTG-IgA)
- 💩 Stool Tests
- FOBT / FIT – GI bleeding
- Faecal calprotectin – IBD vs IBS
- Culture if infection suspected
- 🩻 Imaging
- Ultrasound – liver, gallbladder, kidneys
- CT / MRI – masses, chronic inflammation
- 📹 Endoscopy
- OGD – GERD, gastritis, PUD
- Colonoscopy – IBD, cancer, chronic diarrhoea
🧠 Common Causes of Chronic Abdominal Pain
- 🍽️ Gastrointestinal: GERD, PUD, IBS, IBD, coeliac disease, colorectal cancer
- 🟡 Hepatobiliary: Chronic hepatitis, gallbladder disease
- 🫀 Pancreatic: Chronic pancreatitis
- ♀️ Gynaecological: Endometriosis, PID, ovarian pathology
- 🚻 Renal: Nephrolithiasis, chronic infection
- 🧠 Functional/Psychological: IBS, somatisation, anxiety
💊 Management Principles
- 🎯 Treat the underlying cause
- IBD → immunomodulation
- GERD/PUD → PPIs ± H. pylori eradication
- IBS → diet, antispasmodics, reassurance
- 🥗 Lifestyle Measures
- Dietary modification (e.g. low FODMAP, gluten-free)
- Exercise and smoking cessation
- 🧠 Psychosocial Support
- CBT or mental health referral where appropriate
- 🔁 Follow-Up
- Monitor symptoms and reassess red flags
📊 Summary Table – High-Yield Causes
| Cause |
Key Features |
Investigations |
Management |
| GERD |
Heartburn, regurgitation, worse post-meals |
OGD ± pH monitoring |
PPIs, lifestyle changes |
| IBS |
Crampy pain, bloating, relief after defecation |
Clinical + normal tests |
Low FODMAP, antispasmodics |
| IBD |
Diarrhoea ± blood, weight loss |
Colonoscopy, calprotectin |
5-ASAs, immunotherapy |
| Chronic Pancreatitis |
Epigastric pain → back, steatorrhoea |
CT/MRI, EUS |
Enzymes, analgesia |
| Endometriosis |
Cyclical pelvic pain, dyspareunia |
USS, laparoscopy |
Hormonal ± surgery |
📌 Teaching pearls:
• Weight loss, anaemia, nocturnal symptoms = organic disease until proven otherwise
• Normal investigations + pain relief with defecation strongly suggest IBS
• Chronic pain deserves explanation, reassurance, and follow-up — not dismissal
