Role of specific antibiotics in Mycobacterium ulcerans (Buruli ulcer) management
Buruli ulcer, a disease caused by Mycobacterium ulcerans, is largely a problem of the poor in remote rural areas and, since 1980 has emerged as an important cause of human suffering. After tuberculosis (TB) and leprosy, Buruli ulcer is the third most common mycobacterial disease. In May 2004, the Fiftyseventh World Health Assembly adopted a resolution on Buruli ulcer which called for intensified research to develop tools to diagnose, treat and prevent the disease (1).
MacCallum et al. were the first to describe M. ulcerans in Australia in 1948 (2). The term Buruli ulcer came from Buruli county in Uganda where large numbers of cases were described in the 1960s (3). The condition has been reported or suspected in more than 30 countries worldwide, mainly in tropical and subtropical regions, and the numbers of reported cases are growing. Africa is the worst affected region (4). Other important foci are in Australia (5, 6), French Guiana (7) and Papua New Guinea (8, 9).
More than 50% of those affected are children under the age of 15 years who live in remote rural areas and have little or no access to health services (10, 11). About 90% of patients in Africa present too late, with extensive lesions that cause severe disabilities (12). Mortality is low but disability is high: a recent study estimated that 66% of those with healed lesions have disabilities (13). The median age of this group was 12 years.
Until recently, surgery often involving extensive excision, with or without skin grafting, was the only available treatment. However, because of inadequate surgical capacities in most affected areas of endemic developing countries, access to surgery has been very limited; moreover, where such capacities are available, the cost of surgery is far beyond the means of most of those severely affected (10). In addition, because of the need for prolonged hospitalization – averaging at least three months – limited bed capacity in hospitals where surgical treatment is possible further reduces the number of patients who can be admitted and treated. Recurrence rates after surgical treatment are variable and depend upon the experience of the doctor and the severity of the disease. In a one-year follow-up after excision of small early lesions in the Amansie West district of Ghana, Amofah et al. (14) estimated a 16% recurrence rate. Others have reported recurrence rates of 28%, mainly among late severe cases (11, 15).
Recurrences cause additional human suffering, inflate treatment costs and often frustrate successful management of the disease (16). In view of these difficulties, the need to develop drug treatment has been one of the major research priorities of the World Health Organization (WHO) since the establishment of the Buruli Ulcer Initiative in 1998 (17, 18).