Abdominal Actinomycosis Table 3. Pre-Existing Diagnosis before Intrabdominal Acti- nomycosis Pre-existing diagnosis No. of patients (n = 22), % Diverticulitis 2 (9.0) PID 2 (9.0) Pelvic mass 5 (22.8) Tubovarian abscess* 5 (22.8) Appendicitis 3 (13.6) Lymphoma 3 (13.6) Endometriosis 1 (4.5) Pelvic abscess 1 (4.5) *One patient with combined sigmoid colon fistula. PID, pelvic inflammatory disease. A B Fig. 1. 10.3 ×9.3 cm ovoid mass on the serosal surface of the cecum and ascending colon with ulceration. The cut surface demonstrates typical light gray color with necrosis. or ultrasonography was done in all patients and detected intrabdominal mass or abscess but failed to give a definite diagnosis. The median operative time was 140 (range, 90 - 420) minutes and the median blood loss was 250 (range, 150 - 800) mL. The mean size of tumor was 5.5 (range, 2.5 - 11.0) cm. Sixty percent (n = 12) of female patients had IUD. The patients had been wearing IUD for an average of 7 years, and 15% had been wearing an IUD for 3 years or less. Confirmation of the diagnosis of actinomycosis was done by histology in all cases. Microscopically, each of the specimens showed chronic inflammatory reactions with sulfur granules (Figs. 1 and 2). None of the patients under- went percutaneous biopsy. There were no cancer cells found in all patients. The average time to definitive diagnosis was 10.6 days (range, 4 - 19 days). After a median follow up of 37.5 months (range, 6.6 - 23.1 months), recurrence was not seen in any patients. The antibiotic of choice was IV penicillin, however, one patient was given ciprofloxacin due to penicillin allergy. The duration of treatment was 3 months in twelve patients, 6 months in five patients, 4 months in two patients and 1 month in two patients who refused to continue. Fig. 2. (A) A actinomycotic abscesses containing sulfur granules with radiating filaments (H & E, ×100). (B) A magnified view of the characteristic sulfur granule (H & E, ×200). DISCUSSION Actinomycosis was first diagnosed in a live patient by Ponfick in 1879.11 It is a chronic suppurative disease caused by an anaerobic, filamentous Gram positive bacteria.12 Actinomycosis Israelii is a constant part of the microflora in the human oral cavity, gastrointestinal and genital tracks.12,13 The organism is unable to cross normal mucosal barrier, therefore, opportunistic infections can occur only in context of underlying local disease such as trauma, surgery, or a foreign body which is significant enough to penetrate this barrier. Once the organisms have penetrated the mucosa, spread by continuity seems to be the primary method of intrabdominal propagation. Lymphatic and hematogenous spread is uncommon,14,15 although there is a hematogenous and lymphatic spread with nodal involvement reported.16 Clinically, the disease follows an indolent course and the initial presentation usually includes lower abdominal pain and fever with or without a palpable mass as was seen in our series. Since symptoms and signs are not specific, the diagnosis is often delayed and only 10% of cases are diag- Yonsei Med J http://www.eymj.org Volume 50 Number 4 August 2009 557