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Background. Several diagnostic laboratory methods are available for case confirmation of Buruli ulcer disease. This study assessed the sensitivity of various diagnostic tests in relation to clinical presentation of the disease, type of diagnostic specimen, and treatment history.Methods. Swab samples, 3-mm punch biopsy tissue specimens, and surgically excised tissue specimens from 384 individuals with suspected Buruli ulcer disease were obtained at 9 different study sites in Ghana and were evaluated with dry reagent-based polymerase chain reaction (PCR), microscopic examination, culture, and histopathological analysis. The study subjects presented with nonulcerative and ulcerative lesions and were divided into 3 treatment groups: (1) previously untreated patients scheduled for antimycobacterial treatment, (2) patients treated with surgery alone, and (3) patients treated with surgery in combination with previous antimycobacterial treatment.Results. Of 384 suspected cases of Buruli ulcer disease, 268 were confirmed by at least 1 positive test result. The overall sensitivity of PCR (85%) was significantly higher than that of microscopic examination (57%) and culture (51%). After data were stratified by treatment group, type of lesion, and diagnostic specimen type, analysis revealed that PCR of 3-mm punch biopsy tissue specimens (obtained from previously untreated nonulcerative lesions) and of swab samples (obtained from previously untreated ulcers) had the highest diagnostic sensitivity (94% and 90%, respectively). Although duration of the disease did not significantly influence the sensitivity of any test, previous antimycobacterial treatment was significantly associated with decreased sensitivity of PCR and culture.Conclusions. Across all subgroups, PCR had the highest sensitivity. PCR assessment of 3-mm punch biopsy tissue specimens proved to be the best diagnostic tool for nonulcerative lesions, and PCR assessment of swab samples was the best diagnostic tool for ulcerative lesions. For monitoring of antimycobacterial treatment success within controlled trials, however, only culture is appropriate.

Previous investigations have revealed that Mycobacterium ulcerans is extensively distributed spatially throughout ulcerative lesions, including in the margins of excised tissue. In contrast, bacilli in pre-ulcerative lesions are assumed to be concentrated in the center of the lesion. In order to assess the extent to which the surgical excision of pre-ulcerative lesions is capable of removing all infected tissue, we subjected the excision margins of pre-ulcerative lesions to laboratory analysis. Eleven patients with laboratoryconfirmed pre-ulcerative lesions were included in the study. The diameter of the lesion and excised tissue and the “surgical distance” between the border of the lesion and excision margin were measured. The entire excision margin was cut into segments and subjected to IS2404 PCR. The results from the PCR analysis on the samples of excision margins were highly significantly associated with the surgical distance (p < 0.001). The margin samples of nodules were significantly more often PCR positive than the plaques (p = 0.025). The size of the lesion and the size of the excised tissue did not significantly influence the PCR results. Statistically, a surgical distance of more than 9 mm was found to reduce the risk of remaining infected tissue to less than 10%, that of 13 mm to reduce the risk to less than 5%, and that of 25 mm to reduce the risk to nearly 0%. The results of this study show that in preulcerative Buruli ulcer disease, bacilli may extend beyond the actual size of the lesion and that there is a strong correlation between the presence of M. ulcerans in the margin samples and the surgical distance. Excision with a surgical distance of 25 mm avoided the risk of remaining mycobacteria in this study. However, no recurrences occurred in the patients with M. ulcerans-positive excision margins. The need of postoperative antimycobacterial treatment in these patients remains to be determined.

Background Because of the multifaceted clinical presentation of Buruli ulcer disease, misclassification of clinically diagnosed cases may occur frequently. Laboratory tests for the confirmation of suspected cases include microscopic examination, culture, polymerase chain reaction (PCR), and histopathologic examination. However, microscopic examination, the only test usually available in areas of endemicity, has a low sensitivity. Methods To make a highly sensitive diagnostic method locally available, dry reagent-based PCR (DRB-PCR), which is well adapted to tropical conditions, was pilot-tested in Ghana. Subsequently, the assay was used for the routine diagnosis of Buruli ulcer disease over a period of 2 years. The method was compared with other diagnostic tests to evaluate its performance under field conditions. Results The interassay agreement rate between DRB-PCR and standard PCR was 91.7% for swab specimens and 95% for tissue specimens. Among all of the locally available tests, DRB-PCR revealed the highest overall positivity ratio. Sixty percent of patients with clinical diagnoses of Buruli ulcer disease had the diagnoses confirmed by DRB-PCR of swab or tissue specimens, compared with 30%-40% of patients who had diagnoses confirmed by microscopic examination of swab or tissue specimens. The positivity ratio of DRB-PCR varied considerably when analyzed per treatment center. Standardization of specimen collection resulted in a 30% increase in the positivity ratio of the assay, compared with that in the pilot-testing phase. Conclusions DRB-PCR is a reliable tool for the diagnosis of Buruli ulcer disease. However, PCR assays are suitable for detection only during early stages of the disease, when samples still contain bacilli. The quality of clinical diagnosis and the quality of diagnostic specimens strongly influence the positivity ratio.

Similar to other mycobacterial diseases, susceptibility to Buruli ulcer (Mycobacterium ulcerans infection) may be determined by host genetic factors. We investigated the role of SLC11A1 (NRAMP1) in Buruli ulcer because of its associations with both tuberculosis and leprosy. We enrolled 182 Buruli ulcer patients (102 with positive laboratory confirmation) and 191 healthy neighbourhood-matched controls in Ghana, and studied three polymorphisms in the SLC11A1 gene: 30 UTR TGTG ins/del, D543N G/A, and INT4 G/C. Finger prick blood samples from study subjects were dried on filter papers (FTA) and processed. D543N was significantly associated with Buruli ulcer: the odds ratio (adjusted for gender, age, and region of the participant) of the GA genotype versus the GG genotype was 2.89 (95% confidence intervals (CI): 1.41-5.91). We conclude that a genetic polymorphism in the SLC11A1 gene plays a role in susceptibility to develop Buruli ulcer, with an estimated 13% population attributable risk.

OBJECTIVES To evaluate former Buruli ulcer disease (BUD) patients to assess the factors associated with functional limitations and subsequent employment or schooling. METHODS The previously validated Buruli ulcer functional limitation score (BUFLS) questionnaire and interviews about educational and professional consequences incurred by BUD. RESULTS Of 638 participants, 362 (57%) had a functional limitation after a median period of almost 4 years after treatment for BUD. A lesion on a joint, older age, female gender, a lesion on a distal part of an extremity and a persistent wound were found to be independent risk factors for stopping work or education. The same risk factors applied to the development of a functional limitation. Both functional limitations and financial difficulties due to BUD disease often led to job loss and school dropout. CONCLUSIONS Rehabilitation programmes are urgently needed to diminish the suffering from the functional limitations and employment or schooling problems caused by BUD.

Background. Morbidity due to Buruli ulcer disease (BUD), a cutaneous infection caused by Mycobacterium ulcerans, has been increasingly recognized in rural West Africa. The source and mode of transmission remain unknown.Methods. To identify BUD risk factors, we conducted a case-control study in 3 BUD-endemic districts in Ghana. We enrolled case patients with clinically diagnosed BUD and obtained skin biopsy specimens. M. ulcerans infection was confirmed by at least I of the following diagnostic methods: histopathologic analysis, culture, polymerase chain reaction, and Ziehl-Neelsen staining of a lesion smear. We compared characteristics of case patients with confirmed BUD with those of age- and community-matched control subjects using conditional logistic regression analysis.Results. Among 121 case patients with confirmed BUD, leg lesions (49%) or arm lesions (36%) were common. Male case patients were significantly more likely than female case patients to have lesions on the trunk (25% vs. 6%; P = .009). Multivariable modeling among 116 matched case-control pairs identified wading in a river as a risk factor for BUD (odds ratio [OR], 2.69; 95% confidence interval [Cl], 1.27-5.68; P = .0096). Wearing a shirt while farming (OR, 0.27; 95% Cl, 0.11-0.70; P = .0071), sharing indoor living space with livestock (OR, 0.36; 95% Cl, 0.15-0.86; P = .022), and bathing with toilet soap (OR, 0.41; 95% Cl, 0.19-0.90; P = .026) appeared to be protective. BUD was not significantly associated with penetrating injuries (P = .14), insect bites near water bodies (P = .84), bacille Calmette-Guerin vaccination (P = .33), or human immunodeficiency virus infection (P = .99).Conclusions. BUD is an environmentally acquired infection strongly associated with exposure to river areas. Exposed skin may facilitate transmission. Until transmission is better defined, control strategies in BUD-endemic areas could include covering exposed skin.

The reliability and validity of the earlier developed Buruli ulcer functional limitation score (BUFLS) questionnaire was assessed. Of 638 former Buruli ulcer patients (of 678 individuals examined), sufficient items on daily activities ( 13 of the 19) were applicable to calculate a score. To determine the validity, the functional limitation scores of the 638 individuals were compared with the global impression of the limitations, range of motion (ROM), and the social impact (change of occupation or education) of Buruli ulcer. To determine inter-observer reliability, the functional limitation score was reassessed in 107 participants within one and three weeks after the first interview by another interviewer and interpreter. Both global impression and ROM correlated well with the functional limitation scores ( 0.66 and 0.61). The inter-observer reliability of 107 participants as measured by an intra-class correlation coefficient of 0.86 was very good. The functional limitation scores measured in the second assessment were significantly higher than in the first assessment. This should be taken into account when the functional limitation score is used for the individual patient. The BUFLS can be used as for between group comparisons of endpoints in clinical trials and in the planning of resources. tations. 5 A reduction in the range of motion (ROM) was found in 58% of the former Buruli ulcer patients in Ghana when using a goniometer. Instead of measuring the physical limitations in ROM of joints, a simple and functional scoring system to assess nature and severity of the impairment on carrying out daily activities as a result of Buruli ulcer has been proposed. 6 Based on frequency endorsement and applicability, a ques- tionnaire with 19 items of daily activities was developed. The questionnaire has a good internal consistency ( 0.89). 7,8 In this study, the validity and reliability of this questionnaire was analyzed.

After tuberculosis and leprosy, Buruli ulcer (BU), caused by Mycobacterium ulcerans , is the third most common mycobacterial disease in immunocompetent humans. The disease occurs in tropical countries, with foci in West Africa, Central Africa, and the western Pacific. BU is defined as an infectious disease involving the skin and the subcutaneous adipose tissue characterized by a painless nodule, papule, plaque, or edema, evolving into a painless ulcer with undermined edges and often leading to invalidating sequelae. Due to the fundamental lack of understanding of modes of transmission, disease control in endemic countries is limited to early case detection through improved active surveillance and surgical treatment. The laboratory confirmation of BU is complicated by the absence of a diagnostic “gold standard.” Therefore, misclassification and delayed diagnosis of BU may occur frequently, causing a considerable socioeconomic impact in terms of treatment costs due to prolonged hospitalization. In order to respond to the urgent need to develop reliable tools for early case detection and to overcome technical difficulties accompanying the implementation of diagnostic PCR procedures in tropical countries, a dry-reagent-based PCR formulation for the detection of M. ulcerans in diagnostic specimens has been developed at the Bernhard Nocht Institute for Tropical Medicine. Following technical and clinical validation, the assay has been successfully installed and field tested at the Kumasi Centre for Collaborative Research in Tropical Medicine, Kumasi, Ghana. Preliminary results show an excellent diagnostic sensitivity of >95%.

Helminth infections elicit an immune response potentially enhancing susceptibility to mycobacterial diseases. Schistosomiasis and infection with Mycobacterium ulcerans show a remarkable similarity in epidemiologic characteristics in Ghana. In 2000, a case-control study was conducted in three districts in Ghana endemic for M. ulcerans. One hundred six patients with confirmed M. ulcerans disease and 106 matched community controls were included. Schistosome infection of these patients and controls was measured by an enzyme-linked immunosorbent assay that detected circulating anodic antigen in serum. Fifty percent of the participants tested positive for schistosomiasis. There was no difference in detection rates among patients and matched controls. Similarly, there were no differences in worm burden between patients and controls. These results do not support the hypothesis that susceptibility to M. ulcerans disease is driven by a co-infection with schistosomes.

Buruli ulcer, a disease with long-term consequences, is emerging in west Africa. Thus, a functional limitation scoring system is needed to assess its nature and severity. A list of daily activities was developed for this disease. Following treatment of Buruli ulcer, persons in Benin (n = 47) and Ghana (n = 41) were investigated. Nineteen items were identified with good internal consistency. Participants (median age = 14 years) could not perform 23% of their daily activities. Twenty-nine participants did not have any functional limitation. The average limitation score was 31% in Benin and 15% in Ghana (P = 0.006). The mean limitation score in participants without visible contractures (n = 65) was 13%, whereas patients with visible contractures (n = 20) or an amputation (n = 3) had a score of more than 50%. Validity and reliability should be further analyzed to optimize the scale for use in individual evaluation, as an end point in intervention trials, and in planning of resources needed for the care of patients with functional limitations.

We echo viewpoints presented in recent publications from EcoHealth and other journals arguing for the need to understand linkages between human health, disease ecology, and landscape change. We underscore the importance of incorporating spatialities of human behaviors and perceptions in such analyses to further understandings of socio-ecological interactions mediating human health. We use Buruli ulcer, an emerging necrotizing skin infection and serious health concern in central Ghana, to illustrate our argument.

Standardized antimycobacterial therapy is considered the treatment of choice for Buruli ulcer disease. To assess the prevalence of drug resistance among clinical Mycobacterium ulcerans isolates in Ghana, we conducted a sequence-based approach to detect mutations associated with drug resistance. We subjected clinical samples to direct DNA sequencing of rpoB and rpsL genes and compared culture and whole-genome extracts regarding the efficiency of sequence analysis; 99.1% (rpoB) and 100% (rpsL) of the patients harbored M. ulcerans wild type. In one isolate (0.9%), a point mutation of the rpoB gene at codon Ser522 leading to an amino acid change was detected. Culture extracts yielded a significantly higher sequencing efficiency than whole-genome extracts. Our data suggest a low level of drug resistance in Ghana. However, mutations associated with drug resistance do occur and require monitoring. Improved techniques are necessary to enhance the efficiency of sequence analysis of whole-genome extracts.

In accordance with recent WHO recommendations, this study evaluates the sensitivities of PCR and microscopy for fine-needle aspiration (FNA) versus techniques involving swabs and punch biopsy specimens and suggests that FNA can replace punch biopsies for nonulcerative lesions and may serve as an alternative for ulcerative lesions in cases where scarred edges prevent the collection of swabs.

This study assesses the frequency of recurrences and treatment outcome after surgery of buruli ulcer dis- ease (BUD) with or without concomitant antimycobacterial treatment. Of 129 laboratory-confirmed BUD patients who underwent surgery in two treatment centers in Ghana, 79 (61%) were retrieved for follow-up 4-29 months after the initial treatment. Among 7 (9%) recurrent cases no significant association was found between recurrences and clinical or treat- ment specific factors including antimycobacterial treatment. In 21 (27%) patients, a reduced range of motion (ROM) of one or more joints was detected. Lesions other than nodules, joint involvement, and skin grafting were identified as inde- pendent risk factors. Functional limitations hampering daily activities were perceived by 22% of the patients. Compared with other studies the recurrence rate was relatively low, functional limitations were, however, frequent. This emphasizes the need for improvement of pre- and post-treatment wound care as well as rehabilitation programs.

Because of the emergence of Buruli ulcer disease, the World Health Organization launched a Global Buruli Ulcer Initiative in 1998. This indolent skin infection is caused by Mycobacterium ulcerans. During a study of risk factors for the disease in Ghana, adequate excisional skin-biopsy specimens were obtained from 124 clinically suspicious lesions. Buruli ulcer disease was diagnosed in 78 lesions since acid-fast bacilli (AFB) were found by histopathologic examination. Lesions with other diagnoses included filariasis (3 cases), zygomycosis (2 cases), ulcerative squamous cell carcinomas (2 cases), keratin cyst (1 case), and lymph node (1 case). Thirty-seven specimens that did not show AFB were considered suspected Buruli ulcer disease cases. Necrosis of subcutaneous tissues and dermal collagen were found more frequently in AFB-positive specimens compared with specimens from suspected case-patients (p

Summary Objective In view of technical and financial limitations in areas of endemicity, the current practice and recommendations for the laboratory diagnosis of Buruli ulcer disease (BUD) may have to be reconsidered. We reviewed diagnostic results in order to explore options for a modified, more practicable, cost-effective and timely approach to the laboratory diagnosis of BUD. Methods Diagnostic specimens from 161 clinically diagnosed BUD patients from four different treatment centres in Ghana were subjected to laboratory analysis. The positivity rates of the laboratory assays were compared. Results The number of laboratory-confirmed clinically diagnosed BUD cases with one positive confirmative test was 20% higher than that with two positive confirmative tests. The specificity of microscopy (MIC) and PCR was 96.6% and 100%, respectively. Subsequent analysis of specimens from surgically excised pre-ulcerative tissue-by-tissue MIC and tissue PCR rendered 65% laboratory-confirmed BUD cases. Subsequent analysis of diagnostic swabs from ulcerative lesions by swab smear MIC and swab PCR rendered 70% of laboratory-confirmed BUD cases. Conclusions The specificity of the diagnostic tests used in this study suggests that one positive diagnostic test may be considered sufficient for the laboratory confirmation of BUD. Subsequent application of different diagnostic tests rendered a laboratory confirmation of 65% pre-ulcerative and of 70% ulcerative lesions. Implementation of a stepwise, subsequent analysis of diagnostic specimens will result in considerable cost saving compared with simultaneous testing of specimens by several diagnostic assays. Objectifs Vu les limitations techniques et financieres dans les zones endemiques, la pratique actuelle et les recommandations pour le diagnostic de laboratoire de la maladie de l'ulcere de Buruli (UB) pourraient etre a revoir. Nous avons analyse des resultats de diagnostic afin de d'investiguer des options pour un diagnostic de laboratoire modifie pour l'UB qui soit plus pratique, avec un bon rapport cout/efficacite et une approche plus opportune. Methodes Des specimens de 161 patients UB cliniquement diagnostiques dans quatre centres de traitement differents du Ghana ont ete analyses en utilisant des tests de laboratoire et les taux de positivite ont ete compares. Resultats Le nombre de cas d'UB cliniquement diagnostiques et confirmes par un seul test positif de laboratoire etait 20% plus eleve que celui par deux tests positifs de laboratoire. La specificite de la microscopie et de la PCR etait de 96,6% et 100% respectivement. Une analyse subsequente par microscopie et par PCR, de specimens provenant d'excision de tissu en state pre ulcere a revele 65% de cas d'UB confirmes au laboratoire. L'analyse subsequente par microscopie et par PCR sur des prelevements sur tiges de coton de lesions ulcerees a revele 70% de cas d'UB confirmes au laboratoire. Conclusions La specificite des tests de diagnostic utilises dans cette etude suggere qu'un seul test positif peut etre considere suffisant pour la confirmation de laboratoire de l'UB. L'application subsequente de differents tests de laboratoire a permis une confirmation de laboratoire pour 65% de cas de lesions en stade pre ulcere et 70% de cas de lesions ulcerees. L'implementation d'une analyse par etape des specimens permettra de reduire considerement les couts par rapport au test simultane des specimens par plusieurs tests de diagnostic. Objetivo En vista de las limitaciones tecnicas y economicas existentes en las areas endemicas, deberia reconsiderarse la practica y recomendaciones actuales para el diagnostico en laboratorio de la ulcera de Buruli (UB). Hemos revisado los resultados del diagnostico en laboratorio de la UB, con el fin de explorar opciones para un nuevo enfoque mas practico, costo-efectivo y oportuno. Metodos Se analizaron 161 especimenes de pacientes con diagnostico clinico de UB de cuatro centros diferentes en Ghana. Se comparo la tasa de positividad de las muestras. Resultados El numero de casos clinicos de UB confirmados por laboratorio con una prueba positiva confirmatoria fue un 20% mas alta que con dos pruebas confirmatorias. La especificidad de la microscopia y la PCR fue del 96.6% y 100% respectivamente. Analisis subsiguientes de especimenes diagnosticos de frotis de lesiones ulcerosas mediante microscopia y PCR dieron un 70% de los casos de UB previamente confirmados en el laboratorio. Conclusiones La especificidad de las pruebas diagnosticas utilizadas en este estudio sugiere que una prueba diagnostica positiva puede considerarse como suficiente para la confirmacion en laboratorio de la UB. La aplicacion subsiguiente de diferentes tecnicas diagnosticas tuvo una confirmacion del 65% para lesiones pre-ulcerativas y un 70% para las ulcerativas. La implementacion de un analisis escalonado de los especimenes diagnosticos resultaria en un ahorro considerable, comparado con una evaluacion simultanea de los especimenes utilizando diferentes pruebas diagnosticas.