Microscopic Colitis

Diagnosis

Patients typically have symptoms for several months or years before a diagnosis is made. Symptoms include:

• Watery diarrhea without blood
• Abdominal cramping
• Weight loss
• Urgent bowel movements
• Stool leakage

During an exam, doctors consider a patient's health history. Patients with a history of autoimmune disease such as arthritis, Sjögren's syndrome or celiac disease are sometimes prone to microscopic colitis. Individuals who use multiple drugs, especially nonsteroidal, anti-inflammatory drugs, have a higher risk of developing microscopic colitis.

Scope Tests

Patients with symptoms of microscopic colitis will often undergo a scope test. A colonoscopy allows doctors to view the upper and lower sections of the colon (large intestine). Sigmoidoscopy focuses only on the lower part of the colon. These tests by themselves cannot confirm microscopic colitis; that requires an accompanying biopsy.

Biopsy

To confirm microscopic colitis, doctors take tissue samples (biopsies) of the lining of the colon during a scope test. These samples are studied under a microscope to determine if they contain cells associated with inflammation. Tissue samples must be taken from several areas of the colon, because microscopic colitis occurs in patches.