Background: Iliopsoas abscess (IPA) is an uncommon condition presenting with vague clinical symptoms often resulting in delayed diagnosis and significant morbidity. Treatment strategies remain nonstandardized.
Method: A retrospective review was performed of patients diagnosed with IPA at the Mount Sinai Medical Center from 2000-2007. Records were reviewed with respect to patient demographics, medical history, predisposing and presenting features, diagnostic workup, laboratory results, microbiological investigation, treatment options and hospital course.
Results: IPA was diagnosed in 61 patients (M=32, F=29). The average age was 53 years. The majority of patients presented with pain (95%), gastrointestinal complaints (43%) and lower extremity pain (29%). Mean duration of symptoms was 13 days and mean hospital stay was 25 days. Primary abscess occurred in 11% and secondary in 89%. Underlying causes of secondary abscesses were gastrointestinal in 29%, bacteremia in 13%, immunosupressed state in 8%, and post-procedural in 8%. Broad spectrum antibiotics were prescribed in 100% of cases. Computed tomography (CT) was the most common diagnostic modality used and was successful in 88% of cases. Abscesses were larger than 6 cm in 39%, bilateral in 13% and multiple in 25%. 15% of patients were initially treated with antibiotics alone (Group1) with a success rate of 78%. 89% of these were less than 3.5 cm and the most common cause was bacteremia. 85% of patients initially underwent drainage [open 6% (Group2) and percutaneous 79% (Group3)] with a success rate of 100% and 40%, respectively. Among those cases which did not resolve, 71% ultimately required operative therapy. The majority of these cases had an underlying gastrointestinal etiology. Overall mortality was 5%
Conclusion: IPA remains a therapeutic challenge. Gastrointestinal disease is the most common underlying etiology. CT scan is the diagnostic modality of choice. Antibiotic treatment alone for abscesses less than 3.5 cm and without gastrointestinal cause is typically successful. Percutaneous drainage remains the primary initial treatment modality but rarely is the sole therapy required. Cases with a gastrointestinal etiology are likely to require ultimate operative management.