Imported melioidosis in Japan: a review of cases

Area of Science:

• Infectious Diseases
• Microbiology
• Epidemiology

Background:

• Melioidosis, caused by *Burkholderia pseudomallei*, is endemic in Southeast Asia.
• Cases in Japan are rare and typically linked to travel or residency in endemic areas.
• Understanding the clinical characteristics and risk factors in non-endemic regions is crucial for timely diagnosis and treatment.

Purpose of the Study:

• To review and analyze reported cases of melioidosis in Japan.
• To identify epidemiological features, clinical presentations, and outcomes.
• To highlight the association with underlying conditions and geographic origin.

Main Methods:

• Retrospective review of fourteen reported melioidosis cases in Japan.
• Analysis of patient demographics, exposure history, clinical manifestations, and treatment outcomes.
• Microbiological susceptibility testing of *Burkholderia pseudomallei* isolates.

Main Results:

• All 14 cases involved male patients with a mean age of 52.4 years, with presumed exposure in Southeast Asia.
• Diabetes mellitus was the most common underlying condition (n=8).
• The most frequent infection site was the lung (n=8), followed by bone and skin; 13 cases were acute, and one was chronic. Bacteremia occurred in nine patients. Isolates were susceptible to ceftazidime and carbapenems. Overall mortality was 14.3%.

Conclusions:

• Melioidosis is a rare, imported infection in Japan, predominantly seen in individuals with a history of exposure in Southeast Asia.
• Diabetes mellitus is a significant risk factor for developing melioidosis.
• Prompt diagnosis and appropriate antibiotic treatment, particularly with ceftazidime or carbapenems, are essential for managing this potentially fatal disease.