[Psoas abscesses. Genesis, diagnosis, and therapy].

BACKGROUND: A psoas abscess is a rarely encountered entity with various etiologies and nonspecific clinical presentation, frequently resulting in delayed diagnosis, increased morbidity, and prolonged or recurrent hospitalization. PATIENTS AND METHODS: Between January 1996 and January 2002 we treated ten patients (approximately 54.8, 5 males,5 females). These cases were analyzed retrospectively relative to a review of the literature. RESULTS: CT scanning was decisive in the final diagnosis of psoas abscess. Primary psoas abscess occurred in four cases and six patients had secondary abscesses. In all except one case, the psoas abscess was located on the right side. The causes of primary abscesses were retroperitoneal perforated appendicitis, paravertebral injections for lumboischialgia, Pott's disease, and repeated intravenous drug application in the groin. Five patients underwent retroperitoneal open drainage and four patients CT-guided drainage. One patient with retroperitoneal perforated appendicitis was treated by laparotomy. Staphylococcus aureus, Bacteroides fragilis, and Escherichia coli were the most common infective agents. There was no postoperative mortality and no cases of abscess recurred. CONCLUSIONS: CT scan is a diagnostic "gold standard" for psoas abscess. CT-guided drainage is the method of first choice, but is not possible in all cases. Open retroperitoneal drainage is a standard method of treatment. Postoperative antibiotic therapy is obligatory and should be adapted individually.