Abstract
A 2-year-old girl was referred to our hospital because of fever lasting for 6 weeks. Palpation indicated that she had an abdominal mass in the right lower quadrant without tenderness. Ultrasonography and CT revealed a 6 cm abscess in the right psoas muscle. Laparoscopic examination showed that it was irrelevant to the appendix, cecum or right ovary. We diagnosed it as primary psoas abscess. Percutaneous aspiration and antibiotics therapy were not effective, and a subsequent surgical approach undertaken for continuous drainage successfully resolved the problem. The culture of the pus taken from the abscess showed no microbial growth. In Japan, 17 cases of psoas abscess in the pediatric population have been reported. Primary abscess accounted for 53% of the cases, whereas the remaining 47% were secondary to inflammations such as septic arthritis and appendicitis. Staphylococcus aureus was isolated in 53%, and 71% of the patients were cured by surgical drainage.
