Iliopsoas Abscess: A Narrative Review.

BACKGROUND: Iliopsoas abscess (IPA), a purulent collection in the iliopsoas compartment, is an infrequent disease that is insidious, easily overlooked, life-threatening, and rarely diagnosed early due to nonspecific symptoms and signs. The classic triad of fever, flank pain, and hip movement limitation is present in only 30% of patients. Delays in treatment are followed by increased morbidity and mortality. The microbial etiology of IPA is variable and depends on the geographical area. IPA can be primary or secondary due to the origin of the infectious focus. This review aims to outline the current stage of knowledge of IPA, to emphasize its precocious recognition, and to provide a precise diagnosis using modern imaging according to the hospital patients are seen at, in an effort to reduce the delay in the diagnosis and treatment of IPA.

METHODS: A comprehensive literature search was made from 1980 to December 2024 related to IPA published in English. Key words utilized were "iliopsoas abscess," "retroperitoneal infection," "psoas muscle disorder," "pyogenic psoas abscess," and "psoas abscess." A total of 247 papers were reviewed: 120 case reports, 33 short retrospective series of less than 15 patients, 20 large series with more than 50 patients, and 7 reviews. Additionally, 72 observational studies, 2 systematic reviews, and 2 prospective studies were reviewed. The inclusion criteria encompassed original and review articles published in English.

CONCLUSION: Since the description of IPA with isolated cases, then small series, and recently large retrospective reviews from major hospitals worldwide, the diagnosis and treatment of IPA have improved. With modern imaging techniques (US, CAT scan, and MRI), the diagnosis of IPA has increased, but sequential use of the aforementioned methods is not standardized; besides, there is no uniform treatment for IPA so far. Current management of IPA entails broad-spectrum antibiotics plus percutaneous or surgical drainage.