melena

Introduction

Melena is a black, sticky stool with a characteristic odor, usually indicating GI bleeding proximal to the cecum.

At least 50-60 mL of blood in the GI tract is necessary for occurence of melena in adults.

Etiology

• true melena (secondary to blood) upper GI bleed
  • peptic ulcer disease
  • gastritis or stress ulcers
  • esophageal or gastric varices
  • reflux esophagitis
  • Mallory-Weiss tear
• black stool secondary to other causes (NOT blood)
  • iron
  • licorice
  • bismuth (Pepto-Bismol)
  • blueberries
  • blackberries
  • chocolate (occasionally)

Laboratory

• tests for occult blood positive with true melena
• test for occult blood negative with other causes of black stools

Diagnostic procedures

• upper GI endoscopy after hemodynamic stabilization

More general terms

• sign/symptom

Additional terms

• lower gastrointestinal hemorrhage
• upper gastrointestinal hemorrhage