Effects of purified Clostridium difficile toxin A on rabbit distal colon.

Background & Aims: Antibiotic-associated pseudomembranous colitis in humans is caused by proliferation of Clostridium difficile, which elaborates an enterotoxin toxin A that causes epithelial damage and altered motility in rabbit small intestine. The aim of this study was to assess the effects of toxin A on rabbit distal colonic motility and to relate this to histological damage and inflammatory mediator production.

Methods: Two hundred micrograms per milliliter of toxin A was placed in a distal colonic loop in anesthetized rabbits, and myoelectric activity was recorded for the following 7 hours.

Dysphagia as the sole manifestation of bilateral strokes.

Dysphagia can be caused by a host of factors, most of which are structural or functional. However, despite extensive evaluations, a certain number of patients have unexplained dysphagia. We present an extremely unusual case whereby a patient with an acute left hemispheric cerebral vascular accident presents with dysphagia as his sole complaint and after extensive neurological, gastroenterological, and radiographic examinations is found to have cricopharyngeal dysfunction.

Metronidazole-induced pancreatitis.

We present a case of a 22-yr-old female who developed acute pancreatitis coincident with metronidazole therapy, with documented recurrence when inadvertently rechallenged on two separate occasions. These episodes were unrelated to alcohol ingestion, gallbladder disease, or other known causes of pancreatitis. Only one other case of metronidazole-induced pancreatitis was found in the English literature.