Background: Intra-abdominal abscesses are the third common presentation of melioidosis in Thailand; however, knowledge about the long-term outcomes after received the appropriate therapy are limited.

Objective: To evaluate the clinical course and outcomes of patients with intra-abdominal abscesses due to melioidosis (IAAM).

Materials and Methods: We retrospectively reviewed the data of adult patients who had culture-confirmed melioidosis and presence of intra-abdominal abscesses detected by ultrasonography (US) or computerized tomography (CT) of abdomen between January 2011 and June 2017.

Results: 74 of 356 culture-confirmed melioidosis cases were enrolled with mean (SD) age of 52.4 (12.5) years; 75.7% were male, and nearly 90% of cases had comorbidities. The median duration of illness was 30 days (IQR 13-55). Abdominal pain or tenderness was detected in 40.5% of cases. Splenic abscess (70.3%) was the most common presentation of IAAM, followed by liver abscess (58.1%), and 32.4% of cases had hepatosplenic abscesses. Splenic abscess was significantly higher presented with multiple lesions than liver abscess (p=0.016). Size of abscess in liver was significantly larger than in the spleen (p<0.001) and internal septation was significantly more common in liver than spleen (p<0.001). Mean (SD) fever clearance time was 11.97 (11.04) days and in-hospital mortality was 13.5%. Median (IQR) time of abscesses resolution was 14 (12.57-28.86) weeks. Median (IQR) duration of eradication treatment was 20.9 (20-25.6) weeks.

Conclusion: Intra-abdominal abscesses were presented in about one-fifth of melioidosis, which clinical presentation may be subtle. Abdominal US or CT scan surveillance in patients suspected melioidosis and particularly septicemic or disseminated melioidosis was suggested. Splenic abscess and/or liver abscesses should raise the suspected melioidosis. Abdominal imaging should be performed around 3-month after co-trimoxazole eradicative treatment to determine feasibility of drug discontinuation.

Keywords: melioidosis, intra-abdominal abscesses, Thailand