Good data collection is essential for a better understanding of Buruli ulcer
Authors: Sara Eyangoh
Journal: The Lancet Global Health (2014)

Buruli ulcer is a necrotising skin and soft tissue disease caused by the environmental bacterium Mycobacterium ulcerans. The organism belongs to the same family as those that cause leprosy and tuberculosis, but uniquely, M ulcerans produces the toxin mycolactone, which causes tissue damage. Clinical manifestations include nodules, oedema, and plaques, but the most typical presentation is a large ulcer, usually on the limbs. Buruli ulcer is rarely fatal, but victims are often left deformed and with permanent disability. Under-reporting of the disease is a major problem in several countries. Although advances in treatment have been made with WHO's recommendation1WHOTreatment of Mycobacterium ulcerans disease (Buruli ulcer): guidance for health workers. World Health Organization, 2013http://www.who.int/iris/bitstream/10665/77771/http://apps.who.int//iris/bitstream/10665/77771/1/9789241503402_eng.pdfGoogle Scholar of the use of combined antibiotic treatment with rifampicin and streptomycin for 8 weeks for all types of lesion, laboratory confirmation of clinical diagnosis is still a limiting factor. The development of a PCR test that targets IS2404 (an insertion sequence found on the M ulcerans genome) allows accurate diagnosis, but is available only in reference laboratories that are far from areas endemic for Buruli ulcer.2WHOLaboratory diagnosis of Buruli ulcer: a manual for health care providers. World Health Organization, 2014http://www.who.int/iris/bitstream/10665/111738/http://apps.who.int//iris/bitstream/10665/111738/1/9789241505703_eng.pdf?ua=1Google Scholar Microscopy is available in local health facilities, but is less sensitive than PCR testing. To ensure standardised recording and reporting of cases, WHO developed the Buruli ulcer clinical and treatment 01 form3WHOBuruli ulcer clinical and treatment form–new case. BU 01.N. World Health Organization.http://www.who.int/buruli/control/ENG_BU_01_N.pdf?uaGoogle Scholar to collect clinical and laboratory data for all patients with suspected or confirmed Buruli ulcer. The study by Quentin Vincent and colleagues4Vincent QB Ardant M-F Adeye A et al.Clinical epidemiology of laboratory-confirmed Buruli ulcer in Benin: a cohort study.Lancet Global Health. 2014; (published online June 18.)http://dx.doi.org/10.1016/S2214-109X(14)70223-2Google Scholar in The Lancet Global Health makes good use of data collected with the WHO Buruli ulcer forms. Vincent and colleagues exploited and analysed data for 1357 laboratory-confirmed cases of Buruli ulcer during 10 years at the treatment centre in Pobè, Benin, to provide qualitative and quantitative information about clinical features, diagnosis, treatment, and follow-up. Unlike other published studies that have included clinically diagnosed cases only, this analysis was done on laboratory-confirmed cases of Buruli ulcer, which lends significance to the study. In this study, oedema was most frequent in children, and in the most severe form, led to sequelae in 30% of cases. Plaques and nodules were also more frequent in children and all these clinical presentations decreased significantly with age. Another interesting finding is that osteomyelitis caused by M ulcerans presented without any skin lesion in 20% of cases. Clinicians should therefore pay more attention to the diagnosis of osteomyelitis in young people in endemic areas. They also need to be aware of the special challenges in the diagnosis and management of Buruli ulcer according to lesion type. Some characteristics of the disease reported in other studies were also confirmed by Vincent and colleagues: patients with Buruli ulcer were young, with a median age of 12 years, lesions were mainly localised in the limbs, and 90% of lesions were unifocal. The disseminated non-ulcerative form of M ulcerans infection as oedema is well known and has been reported in severe forms in children. This study highlights the importance of using the WHO form to ensure standard collection of patient data within and across endemic countries. National programmes should encourage health workers to correctly fill out the forms and encourage supervisory activities to ensure their completeness and accuracy. This prospective series of patients is an excellent example of what can be achieved when health workers are encouraged to correctly fill out the forms. The information collected can complement other epidemiological information about patients' habits, location of housing, activities, and other health data related to the environment. The analyses of these data could further enhance understanding of risk factors and help to better develop research hypothesis on the transmission. A key question that needs to be addressed is why children are more vulnerable to the development of non-ulcerative forms of Buruli ulcer disease such as oedema and osteomyelitis. A point-of-care test that is effective, efficient, and easy to implement on the field is urgently needed. Such a test is also essential to exclude other common lesions that could mimic Buruli ulcer and cause false-positive clinical diagnosis. A less invasive sampling method for the oedema and osteomyelitis forms of Buruli ulcer is also needed. Converse and colleagues5Converse PJ Xing Y Kim KH et al.Accelerated detection of mycolactone production and response to antibiotic treatment in a mouse model of Mycobacterium ulcerans disease.PLoS Negl Trop Dis. 2014; 8: e2618Crossref PubMed Scopus (30) Google Scholar reported a successful innovation to detect mycolactone in tissue; future development of this technique could be used as a diagnostic test. Despite substantial knowledge about its clinical manifestations in some endemic countries, confirmation of Buruli ulcer diagnosis is necessary for correct management and reporting of cases. Therefore, health staff should be trained to fill out the WHO form, and physicians should be educated about Buruli ulcer. Early diagnosis and treatment, including measures to prevent disability, are essential for a good outcome. I declare no competing interests. Clinical epidemiology of laboratory-confirmed Buruli ulcer in Benin: a cohort studyOur findings have important clinical implications for daily practice, including enhanced surveillance for early detection of osteomyelitis in boys; systematic search for M ulcerans in osteomyelitis cases of non-specific aspect in areas endemic for Buruli ulcer; and specific disability prevention for patients presenting with osteomyelitis, oedema, or multifocal or large lesions. Our findings also suggest a crucial underestimation of the burden of Buruli ulcer in Africa and raise key questions about the contribution of environmental and physiopathological factors to the recorded heterogeneity of the clinical presentation of Buruli ulcer. Full-Text PDF Open Access