Multicenter External Quality Assessment Program for PCR Detection of Mycobacterium ulcerans in Clinical and Environmental Specimens

Abstract

Background Mycobacterium ulcerans is the causative agent of Buruli ulcer (BU), a necrotizing disease of the skin, soft tissue and bone. PCR is increasingly used in the diagnosis of BU and in research on the mode of transmission and environmental reservoir of M. ulcerans.Methodology/Principal FindingsThe aim of this study was to evaluate the performance of laboratories in detecting M. ulcerans using molecular tests in clinical and environmental samples by implementing sequential multicenter external quality assessment (EQA) programs. The second round of the clinical EQA program revealed somewhat improved performance.Conclusions/SignificanceOngoing EQA programs remain essential and continued participation in future EQA programs by laboratories involved in the molecular testing of clinical and environmental samples for M. ulcerans for diagnostic and research purposes is strongly encouraged. Broad participation in such EQA programs also benefits the harmonization of quality in the BU research community and enhances the credibility of advances made in solving the transmission enigma of M. ulcerans.

Challenges associated with the treatment of Buruli ulcer

“…If the early forms are not treated, extensive skin destruction leads to the formation of an ulcer. Laboratory methods for confirmation of clinical diagnosis include culturing for MU from lesion samples, direct acid‐fast bacilli (AFB) detection by microscopy, and PCR to detect bacterial DNA . The major hallmarks of MU infection, which are also used for histopathological confirmation, are the presence of coagulative necrosis, fat cell ghosts, epidermal hyperplasia, and extracellular clusters of AFB in the absence of major inflammatory infiltrates in central parts of the lesions (Fig.…”

Buruli Ulcer in Australia

“…1 Clinical samples supplied by Professor John Hayman were crucial in the initial validation of the new PCR assay and it was quickly appreciated that IS2404 PCR would be an excellent rapid diagnostic test for BU and soon become the diagnostic test of choice in Australia, due to its quick turn around and exceptional sensitivity and specificity. PCR based on the IS2404 target is now also the gold standard for BU diagnosis in reference laboratories worldwide [16,28,30,31].…”

Thermotherapy of Buruli Ulcer

“…3 Distant healing in a patient with a BU lesion at the right wrist and a laboratory confirmed BU nodule at the left elbow. Both of the lesions healed after heat was applied to the right wrist only (Source: [13]) external quality assessment for PCR detection of M. ulcerans only around one third of the participating laboratories had more than 90% concordant results [16].…”