High Rates of Premature and Potentially Preventable Death among Patients Surviving Melioidosis in Tropical Australia

Abstract

Although the in-hospital mortality of Australian patients with melioidosis continues to decline, the ensuing clinical course of survivors is poorly described. Between January 1, 1998, and January 31, 2019, 228 patients in Cairns, tropical Australia, survived their hospitalization with melioidosis; however, 52 (23%) subsequently died. Death occurred at a median of 3.8 years after discharge, with patients dying at a mean age of 59 years. Only 1/27 (4%) without predisposing conditions for melioidosis died during follow-up, versus 51/201 (25%) with these comorbidities (P = 0.01). Death during follow-up was more likely in patients with chronic lung disease (OR [95% CI]: 4.05 (1.84-8.93, P = 0.001) and chronic kidney disease (OR [95% CI]: 2.87 [1.33-6.20], P = 0.007), and was most commonly due to infection and macrovascular disease. A significant proportion of Australians surviving hospitalization with melioidosis will die soon after discharge, usually prematurely and frequently from preventable conditions. A more holistic approach is required to their care. Melioidosis, a disease caused by the environmental Gramnegative bacillus Burkholderia pseudomallei, is estimated to kill almost 90,000 people globally every year. 1 In Southeast Asia, where the disease is endemic, the in-hospital mortality exceeds 40%. 2 Melioidosis is also endemic in tropical Australia, but early recognition and access to high-quality intensive care unit (ICU) support in the country's well-resourced health system have reduced the disease's case fatality rate to approximately 10%. 3,4 Melioidosis is an opportunistic infection, with disease developing after only one of every 4,600 exposures. 5 Indeed, in tropical Australia, melioidosis is uncommon in the absence of its classically associated risk factors, which include diabetes mellitus, hazardous alcohol use, chronic kidney disease (CKD), chronic lung disease, and immunosuppression. 3 As more Australians survive their acute infection, there is the opportunity to address these comorbidities more aggressively, with the goal of improving long-term outcomes. This study examined the post-discharge course of patients who survived their hospitalization with melioidosis and aimed to determine whether advances in the acute management of the disease were matched by the patients' long-term outcomes. It was performed at Cairns Hospital, a 531-bed, tertiary referral center located in Far North Queensland, tropical Australia. The hospital serves a population of 280,000, almost 12% of whom identify as Indigenous Australians. Its laboratory is the region's primary public microbiology provider. All patients with a positive culture for B. pseudomallei between January 1, 1998, and January 31, 2019, were eligible for the study. Hospital records were reviewed to determine the patients' demographics, their clinical presentation, their comorbidities, and their clinical course. Comorbidities and complications were defined as described previously. 6 If the presence of a comorbidity or complication was not documented, it wa...

Examination of the independent contribution of rheumatic heart disease and congestive cardiac failure to the development and outcome of melioidosis in Far North Queensland, tropical Australia

“…As the case-fatality rate from melioidosis declines in Australia, there is a growing focus on the diagnosis of the comorbidities that predispose patients to the infection, which are also associated with subsequent premature, and frequently preventable, death. Indeed, identification of these conditions and optimisation of their subsequent management is now part of routine clinical care of patients diagnosed with melioidosis in Australia [ 2 , 3 ]. Renal impairment will be biochemically apparent, but patients should be screened for diabetes and asked specifically about hazardous alcohol consumption, and symptoms consistent with chronic lung disease and immunosuppression.…”

“…Identifying these comorbidities is essential as they are closely linked to long term outcomes. While the case-fatality rate from melioidosis is now <10% in Australia, the five-year mortality of patients with predisposing conditions who survive their melioidosis is up to 23%, higher than that of many cancers [ 2 , 3 ]. Identifying and optimising the subsequent management of these comorbidities is likely to improve patients’ long-term outcomes.…”

Melioidosis in Australia

“…Melioidosis is a disease complex attributed to a multi-competent Gram-negative bacillus, B. pseudomallei. High rates of mortality in acute melioidosis survivors remain an unresolved problem 33…”

Melioidosis: A Neglected Cause of Community-Acquired Pneumonia

“…One Australian cohort found that 23% of survivors subsequently died at a median of 3.8 years after hospital discharge. 140 Death during follow-up was more likely in patients with chronic lung disease (odds ratio: 4.05). 140 Even survivors of sepsis from western countries have been shown to have a mortality up to 40% within the first year, 141 emphasizing the need for a more holistic approach to management beyond the acutely infectious period.…”