Based on the overall clinical picture and the magnetic resonance imaging findings, we believe that the patient has had a recurrent psoas abscess secondary to right hip septic arthritis. The previous histologic findings, blood and pus culture results, and laparotomy yielded no clues regarding the etiology of the recurrent abscess. The patient subsequently underwent right hemiarthroplasty, and he recovered uneventfully.
Iliopsoas abscess is a relatively uncommon condition and can present with vague clinical features. Its nonspecific symptoms and occult clinical course are responsible for delayed diagnosis and misdiagnosis.1It was first described by Dr Mynter in 1881, who referred to it as “psoitis.”2It may occur as a primary infection of the psoas space or as a secondary abscess from the direct extension of infection of adjacent organs. In primary iliopsoas abscess, the source of infection is unknown and the most common pathogen is Staphylococcus aureus(88.4%).2Iliopsoas abscess is associated with certain groups of patients,3such as intravenous drug users and those with diabetes mellitus, AIDS, renal failure, and immunosuppression. Secondary iliopsoas abscess3has many causes: gastrointestinal (Crohn disease, diverticulitis, appendicitis, and colorectal cancer), musculoskeletal (vertebral osteomyelitis, septic arthritis, and sacroiliitis), genitourinary (urinary tract infection, cancer, and extracorporeal shock wave lithotripsy), vascular (infected abdominal aortic aneurysm and femoral vessel catheterization), and miscellaneous (endocarditis, intrauterine contraceptive device, and suppurative lymphadenitis).
Clinical diagnosis is often difficult because it is a rare condition and because specific symptoms are absent.4Symptoms suggestive of iliopsoas abscess include fever; pain in the back, flank, and abdomen; and hip flexion contracture. Other symptoms include malaise, nausea, and weight loss.
Blood test results show increased inflammatory markers, and ultrasonographic imaging is useful. However, CT or magnetic resonance imaging is the key investigation in diagnosing iliopsoas abscess. The traditional management of iliopsoas abscess is surgical evacuation and an adequate antibiotic drug regimen. After the development of image-guided percutaneous treatment in the early 1980s, percutaneous aspiration and drainage became available for the treatment of intra-abdominal collections.5Image-guided percutaneous drainage can be performed using either ultrasonography or CT, with the latter being the preferred option because it can demonstrate the entire extent of the abscess, allows better visualization of possible associated pathologic findings in adjacent structures, and is safer.5
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Correspondence:Mahmud Saedon, MB, ChB, Surgical Department, Leighton Hospital, Middlewich Road, Crewe CW1 4QJ, England (firstname.lastname@example.org).
Accepted for Publication:January 22, 2007.
Author Contributions:Study concept and design: Saedon. Acquisition of data: Saedon. Analysis and interpretation of data: Saedon, Shore, and Hanafy. Drafting of the manuscript: Saedon. Critical revision of the manuscript for important intellectual content: Saedon, Shore, and Hanafy. Administrative, technical, and material support: Saedon and Hanafy. Study supervision: Shore and Hanafy.
Financial Disclosure:None reported.
Image of the Month—Diagnosis. Arch Surg. 2008;143(9):914. doi:10.1001/archsurg.143.9.914