Sri Lankan National Melioidosis Surveillance Program Uncovers a Nationwide Distribution of Invasive Melioidosis

Abstract

Abstract. The epidemiologic status of melioidosis in Sri Lanka was unclear from the few previous case reports. We established laboratory support for a case definition and started a nationwide case-finding study. Suspected Burkholderia pseudomallei isolates were collated, identified by polymerase chain reaction assay, referred for Matrix Assisted Laser Desorption Ionization-Time of Flight analysis and multilocus sequence typing (MLST), and named according to the international MLST database. Between 2006 and early 2014, there were 32 patients with culture-confirmed melioidosis with an increasing annual total and a falling fatality rate. Patients were predominantly from rural communities, diabetic, and male. The major clinical presentations were sepsis, pneumonia, soft tissue and joint infections, and other focal infection. Burkholderia pseudomallei isolates came from all parts of Sri Lanka except the Sabaragamuwa Province, the south central hill country, and parts of northern Sri Lanka. Bacterial isolates belonged to 18 multilocus sequence types, one of which (ST 1137) was associated with septicemia and a single-organ focus (Fisher's exact, P = 0.004). Melioidosis is an established endemic infection throughout Sri Lanka, and is caused by multiple genotypes of B. pseudomallei, which form a distinct geographic group based upon related sequence types (BURST) cluster at the junction of the southeast Asian and Australasian clades.

Endocarditis in melioidosis

“…In view of the emergence of melioidosis in Sri Lanka, clinicians should have a high index of suspicion in at risk populations.As many medical laboratory technicians are unfamiliar with the colony appearance of B. pseudomallei, it may be misinterpreted as Pseudomonas, as in our case. Adequate training and the resources should be available for accurate identification [1]. Although antibody titres are usually >320 in culture positive cases, low titres, as seen in our patient, do not exclude melioidosis.…”

“…Melioidosis, caused by Burkholderia pseudomallei, is a potentially fatal, emerging infection in Sri Lanka [1,2]. Although B.pseudomallei is known to infect almost every organ and system of the human body, infection of the heart valves is rare [3,4].…”

Burkholderia cepacia; an unusual cause of multiple splenic abscesses : A case report

“…5 Since a recent surveillance program found nation-wide distribution of invasive melioidosis in Sri Lanka 6 it was considered in the differential diagnosis of this patient. Melioidosis antibodies are considered positive depending on the endemicity of the region concerned.…”

Melioidosis: a neglected tropical disease

“…Active surveillance has established that melioidosis is endemic in Sri Lanka, with a wide geographic and demographic distribution [18,19]. Methodical case finding, education of laboratory staff and clinicians and laboratory capability-building with external reference centre support was able to reveal the widespread distribution of a previously undetected infection.…”