Mycobacterium Ulcerans Disease clinical trials

Pathogenesis and Management of M. Ulcerans Disease, Buruli Ulcer

Buruli ulcer is a neglected tropical disease caused by infection with Mycobacterium ulcerans (Mu) in rural parts of West Africa. It causes large skin ulcers mainly in children aged 5 to 15 years. Access to treatment is limited and many cases present late. There have been major advances in understanding the mechanism of disease together with improved diagnosis and management. The aim of the proposed studies is to identify markers predictive of a rapid response to antibiotic treatment and to investigate the pathogenesis of paradoxical reactions and oedematous lesions in Mu disease. Infection with Mu results in a nodule under the skin which enlarges and breaks down to form an ulcer. This is because Mu produces a toxin that spreads outwards and damages subcutaneous tissue. In recent years it has been found that antibiotic treatment for 8 weeks with daily tablets and intramuscular injections heals ulcers. This is unpleasant and it would be better if the treatment could be shortened. Our previous studies suggest this may be possible. Therefore a wide range of tests will be investigated in order to identify markers for people in whom the infection is at an early stage with low numbers of Mu bacteria and low levels of toxin in the skin. During antibiotic treatment the rate of healing will be measured to find out which markers are the most reliable. In some patients new areas of inflammation develop despite treatment and this is called a paradoxical reaction. The immune response to Mu will be investigated serially during antibiotic treatment to investigate the cause of paradoxical reactions. About 15% of patients have oedematous disease, the most severe form of Buruli ulcer. We will study the amount of Mu toxin produced by the strain of Mu cultured from patients with this form of the disease. Hypothesis - Buruli ulcer patients that heal rapidly/slowly or develop paradoxical reactions with treatment will have associated predictive viability or serum biomarkers. - Buruli ulcer patients with oedematous disease are associated with larger amounts of mycolactone and viable organisms