Psoas abscess complicating Crohn's disease.

Psoas abscess classically was described as secondary to tubercular spondylitis but now more frequently is a complication of an intraabdominal process such as Crohn's disease. Less well recognized is that the fever, flexion contracture of the hip, and weight loss characterizing psoas abscess may be the first indications of Crohn's disease; in fact, gastrointestinal symptoms may be completely absent. Psoas abscess was the first sign of Crohn's disease in 11 of 46 reported patients. We present three additional patients; two were asymptomatic before psoas abscess formation. Only seven of 26 patients whose sole surgical procedure was drainage had subsequent resolution of the abscess. When drainage was combined with bowel resection, 14 of 18 patients (77.8%) were cured by the initial procedure. Thromboembolic complications occurred in four patients (8.3%). Effective therapy when psoas abscess complicates Crohn's disease, includes appropriate antibiotics, drainage, resection of fistulous intestine, and antithrombotic prophylaxis.