[Pain in the hip area accompanied by a fever]

In 3 patients, 2 women aged 16 and 64 years and 1 man aged 64 years, with pain in the left hip region and fever, the diagnosis psoas abscess was made. After antibiotic treatment and drainage they recovered well. The primary from of psoas abscess is presumably caused by haematogenous spread of bacteria, mostly Staphylococcus aureus. The secondary form is caused by spread of infection from surrounding tissue, mostly gastrointestinal micro-organisms with Crohn's disease and diverticulitis. Painful passive extension and endorotation as well as a painful flexion stress-test of the hip joint can indicate a psoas abscess. Echography and blood cultures should be performed if a psoas abscess is suspected. If echography is inconclusive, CT-scan can establish the diagnosis. The psoas abscess should be treated by percutaneous or surgical drainage combined with antibiotic therapy. The underlying cause of a secondary psoas abscess should be treated separately.