Paper
Images of interest. Gastrointestinal: psoas abscess.
Published Jul 1, 1999 · Marks Rd, M. Tie, Roberts-Thomson Ic
Journal of gastroenterology and hepatology
1
Citations
0
Influential Citations
Abstract
The causes of a psoas abscess vary from country to country and, even within countries, may be influenced by referral patterns and socio-economic profiles. In many parts of Asia, the most common cause is tuberculosis, usually by extension of tuberculous spondylitis (Pott’s disease) into the psoas muscle. In Western countries, the most common causes are direct spread of infection to the psoas muscle from disorders such as Crohn’s disease, appendicitis, pyelonephritis, pancreatic abscesses and perforated cancers. Primary psoas abscesses are unusual but may have increased in frequency over the past decade. Several have been due to Staphylococcus aureus and have occurred in intravenous drug users, some of whom have been positive for the human immunodeficiency virus. The symptoms of a psoas abscess vary with the cause, but most patients have a swinging fever as well as pain in the flank, abdomen or hip. Approximately 20% of patients have a mass in the left or right abdomen. In pyogenic abscesses, blood tests almost always reveal an elevated white cell count while blood cultures are positive in 50–70% of patients. Computed tomography (CT) is the most helpful investigation and examples are shown in Figs 1,2.The scan in Fig. 1 shows an abnormality in the right psoas muscle that contains gas, a pattern which is characteristic of an abscess (arrow). The poorly defined inflammatory mass anterior to the abscess was found at laparotomy to be due to Crohn’s disease with adherent loops of small bowel. The patient was treated by resection of the terminal ileum and operative drainage of the abscess. The scan in Fig. 2 shows enhancement of a diffuse abnormality in the right abdomen which involves the right psoas, the latter with an area of central necrosis (arrow). The patient was an elderly diabetic with chronic pancreatitis who developed a tender mass in the right abdomen. Percutaneous aspiration under CT control revealed filamentous, Gram-positive bacilli consistent with Actinomyces or Nocardia species. A barium enema X-ray was normal and largely excluded colonic actinomycosis with spread to the right psoas. The infection may have developed in retroperitoneal tissue damaged by pancreatic inflammation. Treatment with antibiotics resulted in a gradual reduction in the size of the mass. Although uncommon, psoas abscesses still need to be considered in patients with difficult abdominal pain and fever, particularly if there is coexisting pain in the hip.
Case ReportPsoas abscesses can be caused by tuberculosis, Crohn's disease, appendicitis, pyelonephritis, pancreatic abscesses, and perforated cancers, and may have increased in frequency over the past decade.
Full text analysis coming soon...