What is the differential diagnosis for a 68-year-old male with a 2-month history of constant epigastric pain radiating to the suprapubic region, nausea, bloating, fecal urgency post-prandially, and changes in bowel habits, with a history of (medical conditions) and taking (medications), and presenting with epigastric, suprapubic, and right iliac fossa tenderness?

Differential Diagnosis for Epigastric Pain with Radiation, Post-prandial Symptoms, and Bowel Changes

Most Likely Diagnoses

This clinical presentation most strongly suggests functional dyspepsia with overlapping irritable bowel syndrome (IBS), though peptic ulcer disease, chronic pancreatitis, and colorectal pathology must be excluded given the age, examination findings, and alarm features. 1, 2

Primary Gastrointestinal Disorders

Functional Dyspepsia with Postprandial Distress Syndrome (PDS)

• The constellation of epigastric pain, nausea, bloating, and postprandial symptoms (fecal urgency 15 minutes after eating) fits Rome IV criteria for PDS, which requires bothersome postprandial fullness or early satiation at least 3 days per week 1
• However, the presence of physical examination tenderness (epigastric, suprapubic, right iliac fossa) suggests organic pathology rather than purely functional disease 2
• The 2-month duration meets the Rome IV clinical criteria requiring only 8 weeks of symptoms, though not the full 6-month diagnostic criteria 1

Peptic Ulcer Disease (PUD)

• Constant epigastric pain radiating inferiorly with nausea strongly suggests PUD, which has an incidence of 0.1-0.3% and presents with epigastric pain not relieved by antacids 2
• The absence of weight loss does NOT exclude PUD, as weight loss is present in only a subset of cases 2
• Perforation risk is 2-10% with mortality up to 30%, making this a critical diagnosis not to miss 2

Irritable Bowel Syndrome (IBS)

• Post-prandial fecal urgency (15 minutes after eating), bloating, and constipation changes are classic for IBS, affecting 9-23% of the population 3, 4
• The suprapubic and right iliac fossa tenderness with altered bowel habits suggests IBS-C (constipation-predominant) 3, 4
• IBS frequently overlaps with functional dyspepsia, with up to 40% of patients having both conditions 1

Chronic Pancreatitis

• Epigastric pain radiating through the midline, aggravated by sitting (relieved by leaning forward), with nausea and bloating suggests chronic pancreatitis 1
• Post-prandial symptoms occur due to pancreatic enzyme insufficiency, though fecal urgency rather than steatorrhea is atypical 1
• Fecal elastase testing is warranted to evaluate for pancreatic insufficiency 1

Critical Life-Threatening Diagnoses to Exclude

Acute Coronary Syndrome

• At age 68, myocardial infarction can present atypically with isolated epigastric pain, especially in diabetics and elderly patients, with 10-20% mortality if missed 2, 5
• An ECG must be obtained within 10 minutes and serial troponins at 0 and 6 hours to definitively exclude this 5, 6

Mesenteric Ischemia

• Post-prandial pain (15 minutes after eating) with bowel changes in a 68-year-old raises concern for chronic mesenteric ischemia, particularly if vascular risk factors exist 2
• This is a life-threatening condition with high mortality that presents with "pain out of proportion to examination" 2

Abdominal Aortic Aneurysm (AAA)

• Constant epigastric pain radiating inferiorly in a 68-year-old male warrants consideration of AAA, especially with vascular risk factors 2
• Leaking AAA is immediately life-threatening and must be excluded 2

Colorectal Malignancy

• Age 68 with new-onset constipation over preceding months, right iliac fossa tenderness, and post-prandial symptoms raises concern for right-sided colon cancer 2
• The absence of weight loss does NOT exclude malignancy, as early-stage disease may not cause weight loss 2

Other Important Considerations

Gastroparesis

• Post-prandial nausea, bloating, and epigastric pain suggest gastroparesis, which overlaps significantly with functional dyspepsia 1
• The British Society of Gastroenterology states that "FD and gastroparesis are symptom-based constructs with significant overlapping features, which cannot be fully distinguished on the basis of either symptoms or gastric emptying studies" 1
• Approximately 40% of gastroparesis patients report bloating correlating with nausea and abdominal pain 1

Pelvic Floor Dyssynergia/Dyssynergic Defecation

• Constipation with fecal urgency and suprapubic tenderness suggests functional defecation disorder 1
• Digital rectal examination can identify increased sphincter tone or pelvic floor dyssynergia 1
• This frequently coexists with IBS-C and visceral hypersensitivity 1

Helicobacter pylori Gastritis

• Epigastric pain with nausea and bloating may indicate H. pylori infection, particularly in high-prevalence geographic regions 1, 5
• Testing and treating H. pylori eliminates peptic ulcer mortality risk and ranks first in reducing symptoms at 12 months (RR 0.89; 95% CI 0.78-1.0) 6

Gangrenous Gallbladder

• Though typically right upper quadrant pain, atypical presentations with epigastric pain occur in older adults, who may present with covert signs and symptoms 7
• Early diagnosis is imperative to prevent complications and death in this age group 7

Critical Pitfalls to Avoid

• Missing cardiac causes: Delaying ECG and troponins in a 68-year-old with epigastric pain can be fatal 2, 5
• Attributing persistent symptoms to functional disease: Physical examination tenderness suggests organic pathology and warrants endoscopy regardless of age 2
• Delaying endoscopy in high-risk patients: Age 68 with 2-month persistent symptoms and examination tenderness mandates endoscopy, not empirical PPI trial alone 2, 6
• Ignoring new-onset constipation: In a 68-year-old, this is an alarm feature requiring colonoscopy to exclude colorectal malignancy 2
• Missing mesenteric ischemia: Post-prandial pain in elderly patients with vascular risk factors requires urgent vascular imaging 2