Ulcerative Colitis

A patient passes 15-20 bloody, mucus-laden stools per day yet has no perianal fistulas — that single detail changes the entire care plan and tells you which inflammatory bowel disease you're managing.

Ulcerative colitis (UC) is a chronic inflammatory bowel disease limited to the mucosal and submucosal layers of the colon. It always begins at the rectum and extends proximally in a continuous pattern — no skip lesions. The hallmark presentation is frequent bloody diarrhea with mucus, urgency, tenesmus, and crampy left lower quadrant pain. Stool frequency correlates with severity: mild is fewer than 4 stools/day, severe is more than 6 bloody stools/day with systemic signs (fever >37.5°C, tachycardia, anemia, elevated ESR). Extraintestinal manifestations include erythema nodosum, uveitis, and primary sclerosing cholangitis — PSC is far more associated with UC than with Crohn's. The most feared complication is toxic megacolon: sudden cessation of diarrhea with abdominal distension, fever, and tachycardia signals colonic dilation >6 cm and risk of perforation. Long-standing UC (8-10 years) significantly increases colorectal cancer risk, requiring surveillance colonoscopies every 1-2 years. Nursing priorities include strict I&O tracking, monitoring for dehydration and electrolyte imbalances (especially hypokalemia), assessing stool characteristics, providing perianal skin care, and supporting nutrition — a low-residue diet during flares, advancing as tolerated during remission.

Key Distinctions

Don't confuse UC's continuous rectal-to-proximal mucosal inflammation with Crohn's transmural skip lesions and fistula formation — UC does not produce fistulas, and strictures are rare (when present, biopsy is needed to rule out malignancy). Students mistake sudden cessation of diarrhea as improvement; in UC, it may signal toxic megacolon — a surgical emergency, not recovery. Sulfasalazine treats UC inflammation but requires monitoring for sulfa allergy and folate supplementation — don't confuse its GI-targeted action with systemic immunosuppressants like azathioprine.

Clinical Pearl

When the bloody diarrhea suddenly stops and the belly blows up, think worse — not better. Toxic megacolon until proven otherwise.