Primary actinomycosis of the urachus
Version of Record online: 28 JUN 2008
Volume 83, Issue 1, pages 144–145, January 1999
How to Cite
Micheli, E., Hurle, R., Losa, A., Chinaglia, D., Ranieri, A. and Lembo, A. (1999), Primary actinomycosis of the urachus. BJU International, 83: 144–145. doi: 10.1046/j.1464-410x.1999.00958.x
- Issue online: 28 JUN 2008
- Version of Record online: 28 JUN 2008
A 22-year-old man was referred complaining of hypogastric pain of more than 5 months’ duration. Physical examination showed a hard, fixed, median umbilical-pubic mass infiltrating the abdominal wall. Blood chemistry tests showed no leucocytosis or abnormality in inflammatory index. An abdominopelvic contrast-medium CT scan showed a supravesical hypogastric mass of 6 cm, infiltrating the rectus abdominis muscles (Fig. 1). The hepatic, splenic, pancreatic and renal parenchyma were normal. The initial suggestion was that the mass was a productive lesion starting from the urachus. The findings on cysto-urethroscopy were normal; a median umbilicopubic laparotomy was then carried out and the mass, reaching from the umbilicus to the dome of the bladder, was excised. On gross inspection it contained reactive whitish fibrogranulomatous tissue surrounding a central abscess (Fig. 2). Histological examination detected the typical bacterial colony (Fig. 3) which led to the diagnosis of actinomycosis. The patient was investigated to determine any possible origin of actinomycosis; no dental, mandibular, cardiac, thoracic or abdominal foci were found. The patient was treated with penicillin (20 MU intravenous infusion for 28 days) then amoxicillin (3 g/day orally for 6 months). The patient was followed as an outpatient and one year later is well.
Actinomyces israelii is an anaerobic Gram-positive bacterium, a common commensal of the intestinal flora; infections are generally cervicofacial (63%), thoracic (15%) or abdominal (22%) and usually develop as a consequence of trauma, after surgical operations or in patients with tumours . Primary pelvic actinomycosis is extremely rare and difficult to diagnose. Since Henderson’s description of the relation between pelvic actinomycosis and intrauterine contraceptive devices (IUDs), many cases of ‘pelvic inflammatory disease’ caused by Actinomyces have been reported among women using the IUD [2,3]. However, this pathology rarely arises in the genito-urinary tract, but when it does it may cause mutilating lesions. Cases have been described of ureteric stenosis, and localization in the bladder and retroperitoneum [4–6]. The variety of clinical presentations and the relative infrequency of the disease make diagnosis problematic. The radiological findings are not specific; CT can document the presence and extension of the formation, confirming the infiltrating nature of this disease, which tends to invade surrounding tissues. However, final diagnosis must be based on histological identification of the actinomycotic granules, or culture of Actinomyces. Penicillin is the drug of choice, but the dosages and duration of treatment vary widely. After a high initial parenteral loading dose, it is widely recommended that treatment should be continued orally for several months. The case described here is interesting because to our knowledge there has been no report of actinomycosis occurring in the urachus. Moreover, it arose in a young patient, apparently healthy, with no predisposing conditions. We found no primary focus, and in such cases there may be cryptic locations which require prolonged antibiotic treatment to eradicate.