Which uncommon gastrointestinal diseases across different age groups present with distinctive physical examination findings that enable bedside diagnosis?

Rare GI Pathologies Diagnosable by Physical Examination

Hypertrophic Pyloric Stenosis (HPS)

The pathognomonic physical finding is palpation of the "olive" – a firm, mobile, olive-shaped mass in the right upper quadrant representing the hypertrophied pyloric muscle. 1

• This classic finding occurs in infants (typically 3-12 weeks old) presenting with projectile, non-bilious vomiting 1
• The olive is best palpated during or immediately after feeding, when the stomach is distended 1
• Physical examination may also reveal visible gastric peristaltic waves moving from left to right across the upper abdomen 1
• Common pitfall: The olive can be difficult to palpate if the infant is crying or the abdomen is tense; examination should be performed when the infant is calm and relaxed 1

Intussusception

The classic triad includes intermittent crampy abdominal pain, "currant jelly" stools (bloody mucoid stools), and a palpable sausage-shaped abdominal mass. 1, 2

• The mass is typically palpable in the right upper quadrant or epigastrium, representing the telescoped bowel 1
• Patients may exhibit the "Dance sign" – absence of bowel in the right lower quadrant due to the intussusception pulling the cecum medially 1
• Lethargy between pain episodes is a distinctive feature that should raise immediate concern 1
• Unusual in the first 3 months of life; peak incidence is 6-36 months 1
• Critical pitfall: Early presentation may lack the complete triad; any two components warrant urgent imaging with ultrasound as first-line 2

Gastric Volvulus

Borchardt's triad defines this rare entity: severe epigastric pain with distension, violent retching without productive vomiting, and inability to pass a nasogastric tube. 1

• Physical examination reveals a distended, tympanic upper abdomen with tenderness 1
• This is a surgical emergency requiring immediate intervention 1
• More common in patients with paraesophageal hernias or diaphragmatic defects 1

Rosai-Dorfman-Destombes Disease (RDD) with GI Involvement

Massive, painless cervical lymphadenopathy is the hallmark physical finding, though GI involvement presents with palpable abdominal masses or hepatosplenomegaly. 1

• Bilateral, symmetric, firm, mobile cervical nodes are characteristic 1
• When GI tract is involved (<1% of cases), palpable abdominal masses may be detected, particularly in the right lower quadrant (ileocecal predilection) 1
• Physical examination should include assessment for proptosis, enlarged tongue, skin nodules/papules/plaques, and testicular masses 1
• Distinctive feature: Patients often have concurrent extranodal disease visible on examination (skin lesions, orbital involvement) 1

Acute Mesenteric Ischemia

The pathognomonic clinical feature is "pain out of proportion to physical examination findings" – severe, diffuse abdominal pain with a surprisingly benign abdominal examination. 3

• Early in the course, the abdomen may be soft without significant tenderness, guarding, or rebound despite excruciating pain 3
• As ischemia progresses, peritoneal signs develop with distension, absent bowel sounds, and diffuse tenderness 3
• This carries 30-90% mortality if diagnosis is delayed; immediate CT angiography is mandatory 3
• Critical pitfall: A benign abdominal examination does NOT exclude this diagnosis in elderly patients with cardiovascular risk factors and severe pain 3

Diverticulitis with Complications

Left lower quadrant tenderness with a palpable, tender mass suggests a diverticular phlegmon or abscess. 3

• Accounts for ~30% of large bowel pathology in elderly patients 3
• Physical examination may reveal localized peritoneal signs in the left lower quadrant 3
• Fever, tachycardia, and guarding indicate complicated disease requiring hospitalization 3
• Pitfall: Right-sided diverticulitis occurs in Asian populations and can mimic appendicitis 3

Colorectal Cancer with Obstruction

A palpable abdominal mass combined with progressive abdominal distension and altered bowel habits in elderly patients suggests obstructing colorectal malignancy. 3

• Accounts for 60% of large bowel obstructions in this age group 3
• Digital rectal examination may reveal a palpable rectal mass 3
• Physical findings include distension, tympany, high-pitched bowel sounds, and possible palpable mass 3

Ulcerative Colitis (Severe Attack)

Fever, tachycardia, weight loss, abdominal tenderness, distension, and reduced bowel sounds characterize a severe UC flare. 1

• Blood on digital rectal examination is typical 1
• Mild to moderate disease often has unremarkable physical examination except for rectal bleeding 1
• Key distinction from IBS: Nocturnal symptoms, fever, weight loss, and anemia indicate organic disease (IBD) rather than functional disorder 4
• Physical examination in IBS is characteristically normal 1, 4

Practical Examination Approach

When evaluating for rare GI pathologies, the physical examination should systematically assess:

• Vital signs: Fever (infection/inflammation), tachycardia (hypovolemia/sepsis), weight loss (malignancy/IBD) 1, 3
• Abdominal inspection: Visible peristalsis (HPS), distension (obstruction), surgical scars 1
• Palpation technique: Perform when patient is relaxed; palpate for masses (intussusception, RDD, malignancy), organomegaly, and the pyloric olive 1
• Percussion and auscultation: Assess for tympany (obstruction), absent bowel sounds (ileus/peritonitis), high-pitched sounds (obstruction) 1, 3
• Digital rectal examination: Essential for detecting blood, masses, and assessing sphincter tone 1, 3

The most critical principle: When severe pain exists with minimal physical findings, consider mesenteric ischemia immediately – this discordance is the key diagnostic clue for this lethal condition. 3