ACUTE ACALCULOUS CHOLECYSTITIS - INCIDENCE, RISK-FACTORS, DIAGNOSIS, AND OUTCOME

The objective of this study was to review the incidence, risk factors, methods of diagnosis, and outcome of acute acalculous cholecystitis ( AAC) and to identify the sensitivity and limitations of current radiog raphic modalities used to establish the diagnosis. Our study was a ret rospective chart review in a tertiary-care university hospital. Over a 53-month period, 27 cases of AAC (17 males, 10 females; mean age, 50 years; mean Acute Physiology and Chronic Health Evaluation II score, 1 7) were encountered. Of these, 14 (52%) occurred in critically ill pat ients and 17 (63%) in patients recovering from non-biliary tract opera tions. AAC occurred in 0.19 per cent of surgical intensive care unit a dmissions and accounted for 14 per cent (27 of 188) of all cases of ac ute cholecystitis. Presenting symptoms and laboratory values were nons pecific. Twenty patients had radiographic studies before surgery. Amon g the various radiological studies used for AAC, morphine cholescintig raphy had the highest sensitivity (9 of 10; 90%), followed by computed tomography (8 of 12; 67%) and ultrasonography (2 of 7; 29%). Ten of t he 20 patients had more than one study done preoperatively. All 27 pat ients had an open cholecystectomy. AAC was associated with a high inci dence of gangrene (17 of 27 cases; 63%), perforation (4 of 27; 15%), a nd abscess (1 of 27; 4%). The mortality rate was 41 per cent (11 of 27 ). We conclude that AAC is a rare, but potentially lethal, disease occ urring in critically ill patients and those recovering from non-biliar y tract operations. The clinical presentation is nonspecific, and sign ificant delays in diagnosis result in a high incidence of gangrene, pe rforation, abscess, and death. To improve outcome, a high index of sus picion with early radiographic evaluation, often employing multiple st udies, is necessary. An algorithm for the evaluation of patients for s uspected AAC is proposed.