A 42-year-old female presents to the clinic with a 4-day history of watery diarrhea, abdominal cramping, and fever. She reports that the diarrhea has progressively worsened, with up to 8-10 episodes per day. She describes the abdominal cramps as moderate, intermittent, and located in the lower abdomen. The patient mentions feeling fatigued and nauseous, but has not experienced vomiting. There is no blood or mucus in the stool.

The patient has a history of hypertension, for which she takes enalapril, and recently completed a 10-day course of clindamycin for a dental infection about 2 weeks ago. She has not traveled recently, nor has she had any significant changes in diet. On examination, she appears mildly febrile (38.2°C), and her abdominal examination reveals mild tenderness in the lower abdomen, but no rebound tenderness or guarding. Bowel sounds are hyperactive.

Laboratory tests show a mild leukocytosis (white blood cell count of 12,000/mm³), and stool cultures reveal no pathogens. A stool test for Clostridium difficile toxin comes back positive.

The patient is diagnosed with pseudomembranous colitis, likely secondary to Clostridium difficile infection after antibiotic use.

Key Points:

• Commonly associated with recent antibiotic use (especially clindamycin, cephalosporins, and fluoroquinolones).

• Clostridium difficile overgrowth results in the production of toxins that damage the colonic mucosa, leading to inflammation.

• Symptoms include watery diarrhea, abdominal cramping, and fever.

• Diagnosis is confirmed by stool testing for C. difficile toxin.

• Treatment typically involves oral vancomycin or fidaxomicin, and in severe cases, colectomy may be required.