Improving the clinical recognition, prognosis, and treatment of melioidosis through epidemiology and clinical findings: The Sabah perspective

Abstract

Introduction: Melioidosis is a deadly endemic disease in northern Australia and Southeast Asia, including Sabah, Malaysia, which is caused by the bacterium Burkholderia pseudomallei. It contributes to high fatality rates, mainly due to misdiagnosis leading to the wrong treatment being administered to the patients. Local epidemiology and data on clinical features could assist clinicians during diagnosis and treatment. However, these details are still scarce, particularly in Sabah.

Methods: A retrospective study of 246 culture-confirmed melioidosis cases in Queen Elizabeth Hospital, Sabah, Malaysia was performed between 2016 and 2018. The epidemiological data and clinical and laboratory findings were extracted and analysed.

Results: The annual incidence of culture-confirmed melioidosis cases was estimated to be 4.97 per 100,000 people. The mean age of the patients was 50±15 years. Males and members of the Kadazan-Dusun ethnic group accounted for the majority of the melioidosis cases. The odds ratio analysis indicated that bacteraemic melioidosis in this region was significantly associated with fever (76%), and patients having at least one underlying illness (43%), including diabetes mellitus (32%). Sixty-eight patients (28%) succumbed to melioidosis. Contrary to what is known regarding factors that promote bacteraemic melioidosis, neither patients with fever nor patients with at least one comorbid disease, including diabetes mellitus, were significantly associated with death from melioidosis. There was no statistically significant difference between patients without comorbidities (24, 27%) and those with at least one comorbid disease (26, 25%), including diabetes mellitus (18, 23%). The odds ratios indicate that melioidosis mortality in this region is related to patients showing respiratory organ-associated symptoms (29%), bacteraemia (30%), and septic shock (47%). Burkholderia pseudomallei isolates in this study were highly susceptible to ceftazidime (100%), imipenem (100%), and trimethoprim-sulfamethoxazole (98%).

Conclusions: Information obtained from this study can be used by clinicians to recognise individuals with the highest risk of acquiring melioidosis, estimate an accurate prognosis, and provide effective treatment for melioidosis patients to reduce death from melioidosis.

Fig 1. Distribution of the 246 culture-confirmed melioidosis cases based on ethnic groups sampled during the study and the expected melioidosis cases based on the annual average proportion of the Sabah ethnic groups over the 3 years period (January 2016—December 2018) in Sabah.

(A) The bar chart (blue) shows the distribution of the 246 melioidosis cases according to the ethnic groups. (B) The expected melioidosis cases based on the average annual ethnic groups proportion is shown in the line graph (red).

Fig 2. Distribution of the 246 culture-confirmed melioidosis cases based on the monthly rainfall.

(A) Distribution of the 246 melioidosis cases and average monthly rainfall over the 3 year period (January 2016—November 2018) (r_s = 0.366, p = 0.242). (B) Distribution of the 90 melioidosis cases and monthly rainfall for 2016 (r_s = 0.571, p = 0.053). (C) Distribution of the 94 melioidosis cases and monthly rainfall for 2017 (r_s = 0.352, p = 0.261). (D) Distribution of the 62 cases and monthly rainfall for 2018 (r_s = 0.274, p = 0.415). The bar chart depicts the distribution of melioidosis cases according to the month of admission. The corresponding average monthly rainfall amount (A) and monthly rainfall (B, C & D) in the vicinity of Kota Kinabalu is shown by the line graph.