<i>Mycobacterium ulcerans</i> Disease and Host Immune Responses

Mycobacterium ulcerans is the causative agent of the subcutaneous necrotic condition known as Buruli ulcer (BU).BU is Neglected Tropical Disease. The bacillus is the third most common mycobacteria disease-causing agent after Mycobacterium tuberculosis and Mycobacterium leprae. M. ulcerans produces the toxin-Mycolactone, which plays a key role in the pathophysiological features of the disease. Buruli ulcer has been reported in 34 countries, mainly in the tropics and subtropics. Tropical countries include Benin, Cameroon, Ghana, Democratic Republic of Congo and Nigeria. BU is also prevalent in Queensland, a subtropical region, and in Victoria, a temperate area, all within Australia. The exact mode of the transmission remains unclear. However, M. ulcerans is believed to have an aquatic niche. Initial diagnosis of BU is based on the experience of the clinician, but PCR targeting the M. ulcerans DNA, IS2404, isolation and culture of the bacillus and histopathology are used for confirmation. The current, commonly used methods for confirmatory diagnosis have logistic and resource challenges. Novel cell mediated immunity (CMI) and serology-based tests would be beneficial to provide a more accurate assessment of population exposure.