METHODS: In this study, multi-locus sequence typing (MLST) was performed on clinical B. pseudomallei isolates collected from Kelantan state of Malaysia, patients' clinical data were reviewed and then genotype-risk correlations were investigated.
RESULTS: Genotyping of 83 B. pseudomallei isolates revealed 32 different STs, of which 13(40%) were novel. The frequencies of the STs among the 83 isolates ranged from 1 to 12 observations, and ST54, ST371 and ST289 were predominant. All non-novel STs reported in this study have also been identified in other Asian countries. Based on the MLST data analysis, the phylogenetic tree showed clustering of the STs with each other, as well as with the STs from Southeast Asia and China. No evidence for associations between any of B. pseudomallei STs and clinical melioidosis presentation was detected. In addition, the bacterial genotype clusters in relation with each clinical outcome were statistically insignificant, and no risk estimate was reported. This study has expanded the data for B. pseudomallei on MLST database map and provided insights into the molecular epidemiology of melioidosis in Peninsular Malaysia.
CONCLUSION: This study concurs with previous reports concluding that infecting strain type plays no role in determining disease presentation.
Method: In this study, we developed a rapid, sensitive and specific insulated isothermal Polymerase Chain Reaction (iiPCR) targeting bimA gene (Burkholderia Intracellular Motility A; BPSS1492) for the identification of B. pseudomallei. A pair of novel primers: BimA(F) and BimA(R) together with a probe were designed and 121 clinical B. pseudomallei strains obtained from numerous clinical sources and 10 ATCC non-targeted strains were tested with iiPCR and qPCR in parallel.
Results: All 121 B. pseudomallei isolates were positive for qPCR while 118 isolates were positive for iiPCR, demonstrating satisfactory agreement (97.71%; 95% CI [93.45-99.53%]; k = 0.87). Sensitivity of the bimA iiPCR/POCKIT assay was 97.52% with the lower detection limit of 14 ng/µL of B. pseudomallei DNA. The developed iiPCR assay did not cross-react with 10 types of non-targeted strains, indicating good specificity.
Conclusion: This bimA iiPCR/POCKIT assay will undoubtedly complement other methodologies used in the clinical laboratory for the rapid identification of this pathogen.
METHODS: We reviewed 39 cases of splenic abscesses in a district hospital in Kapit, Sarawak, from January 2017 to December 2018. The demographics, clinical characteristics, underlying diseases, causative organisms, therapeutic methods, and mortality rates were investigated.
RESULTS: There were 21 males and 18 females (mean age, 33.7±2.7 years). Almost all patients (97.4%) had a history of pyrexia. Diabetes mellitus was present in 8 patients (20.5%). Splenic abscesses were diagnosed using ultrasonography and were multiple in all 39 cases. Positive blood cultures were obtained in 20 patients (51.3%), and all yielded B. pseudomallei. Melioidosis serology was positive in 9 of 19 patients (47.4%) with negative blood cultures. All patients were treated for melioidosis with antibiotics without the need for surgical intervention. All splenic abscesses resolved after anti-melioidosis treatment was completed. One patient died (2.6%) as a result of B. pseudomallei septicaemia with multiorgan failure.
CONCLUSIONS: Ultrasonography is a valuable tool for diagnosing splenic abscesses in resource-limited settings. B. pseudomallei was the most common etiological agent of splenic abscesses in our study.