Background
Burkholderia pseudomallei, the causative agent of melioidosis, is intrinsically resistant to a broad range of antibiotics, including aminoglycosides. In Sarawak, Malaysia, a high proportion of melioidosis cases are caused by gentamicin-susceptible isolates. There are limited epidemiological and clinical data on these infections.
Methods
We conducted a retrospective study of culture-confirmed melioidosis among adults admitted to Bintulu Hospital in Sarawak, Malaysia, from January 2011 until December 2016.
Results
One-hundred and forty-eight adults with culture-confirmed melioidosis were identified. Of 129 (87%) tested, 84 (65%) had gentamicin-susceptible B. pseudomallei. The average annual incidence of melioidosis was 12·3 per 100,000 population, with marked variation between districts ranging from 5·8-29·3 per 100,000 population. Rural districts had higher incidences of melioidosis and overwhelmingly larger proportions of gentamicin-susceptible B. pseudomallei infection. Significantly more patients with gentamicin-susceptible infection had no identified risk factors, with diabetes less frequently present in this group. Ninety-eight percent had acute presentations. Pneumonia, reported in 71%, was the most common presentation. Splenic abscesses were found in 54% of those imaged. Bacteremia was present in 88%; septic shock occurred in 47%. Forty-five (35%) patients died. No differences in clinical, laboratory, or outcome characteristics were noted between gentamicin-susceptible and gentamicin-resistant infections.
Conclusions
Gentamicin-susceptible B. pseudomallei infections are common in Sarawak and dominate in the high incidence rural interior regions. Clinical manifestations and outcomes are the same as for gentamicin-resistant B. pseudomallei infections. Further studies are required to determine if all gentamicin-susceptible B. pseudomallei in Sarawak are clonal and to ascertain their environmental drivers and niches.