CASE PRESENTATION: Here, we report two cases of melioidosis from Nepal. Both of them were diabetic male who presented themselves with fever, multiple abscesses and developed sepsis. They were treated with multiple antimicrobial agents including antitubercular drugs before being correctly diagnosed as melioidosis. Consistent with this, both patients were farmer by occupation and also reported travelling to Malaysia in the past. The diagnosis was made consequent to the isolation of B. pseudomallei from pus samples. Accordingly, they were managed with intravenous meropenem followed by oral doxycycline and cotrimoxazole.
CONCLUSION: The case reports raise serious concern over the existing unawareness of melioidosis in Nepal. Both of the cases were left undiagnosed for a long time. Therefore, clinicians need to keep a high index of suspicion while encountering similar cases. Especially diabetic-farmers who present with fever and sepsis and do not respond to antibiotics easily may turn out to be yet another case of melioidosis. Ascertaining the travel history and occupational history is of utmost significance. In addition, the microbiologist should be trained to correctly identify B. pseudomallei as it is often confused for other Burkholderia species. The organism responds only to specific antibiotics; therefore, correct and timely diagnosis becomes crucial for better outcomes.
Case presentation: A 29-year-old man presented with pneumonia and melioidosis septicaemia. His condition was complicated with infective endocarditis and septic emboli to the brain. Despite difficulties in reaching a diagnosis, the patient was successfully treated using intravenous gentamicin and ceftazidime and was discharged well.
Discussion: The role of gentamicin in the treatment of the gentamicin-susceptible strain of B. pseudomallei remains unclear.
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.
CASE PRESENTATION: In September 2010, a 58-year-old diabetic Malaysian male presented with fever and a fluctuant mass on the right side of his neck. B. pseudomallei was isolated from an aspirate of this lesion and there was radiological evidence of disseminated infection in the liver and spleen. The recurrence of clinical symptoms over ensuing months prompted further aspiration and biopsy of a cervical abscess and underlying lymph nodes. Salmonella enterica serovar Stanley and then M. tuberculosis were identified from these specimens by culture and molecular methods. The patient responded to targeted medical management of each of these infections.
CONCLUSION: In endemic settings, a high index of suspicion and adequate tissue sampling are imperative in identifying these pathogenic organisms. Diabetes was identified as a predisposing factor in this case while our understanding of other potential risk factors is evolving.