Providing insight into the incubation period of Mycobacterium ulcerans disease: two case reports.

BACKGROUND: Buruli ulcer caused by Mycobacterium ulcerans is endemic in parts of West Africa and is most prevalent among the 5-15 years age group; Buruli ulcer is uncommon among neonates. The mode of transmission and incubation period of Buruli ulcer are unknown. We report two cases of confirmed Buruli ulcer in human immunodeficiency virus-unexposed, vaginally delivered term neonates in Ghana. CASE PRESENTATION: Patient 1: Two weeks after hospital delivery, a baby born to natives of the Ashanti ethnic group of Ghana was noticed by her mother to have a papule with associated edema on the right anterior chest wall and neck that later ulcerated. There was no restriction of neck movements. The diagnosis of Buruli ulcer was confirmed on the basis of a swab sample that had a positive polymerase chain reaction result for the IS2404 repeat sequence of M. ulcerans. Patient 2: This patient, from the Ashanti ethnic group in Ghana, had the mother noticing a swelling in the baby's left gluteal region 4 days after birth. The lesion progressively increased in size to involve almost the entire left gluteal region. Around the same time, the mother noticed a second, smaller lesion on the forehead and left side of neck. The diagnosis of Buruli ulcer was confirmed by polymerase chain reaction when the child was aged 4 weeks. Both patients 1 and 2 were treated with oral rifampicin and clarithromycin at recommended doses for 8 weeks in addition to appropriate daily wound dressing, leading to complete healing. Our report details two cases of polymerase chain reaction-confirmed Buruli ulcer in children whose lesions appeared at ages 14 and 4 days, respectively. The mode of transmission of M. ulcerans infection is unknown, so the incubation period is difficult to estimate and is probably dependent on the infective dose and the age of exposure. In our study, lesions appeared 4 days after birth in patient 2. Unless the infection was acquired in utero, this would be the shortest incubation period ever recorded. CONCLUSIONS: Buruli ulcer should be included in the differential diagnosis of neonates who present with characteristic lesions. The incubation period of Buruli ulcer in neonates is probably shorter than is reported for adults.

Management of BU-HIV co-infection.

BACKGROUND: Buruli Ulcer (BU)-HIV co-infection is an important emerging management challenge for BU disease. Limited by paucity of scientific studies, guidance for management of this co-infection has been lacking. METHODS: Initiated by WHO, a panel of experts in BU and HIV management developed guidance principles for the management of BU-HIV co-infection based on review of available scientific evidence, current treatment experience, and global recommendations established for management of HIV infection and tuberculosis. RESULTS: The expert panel agreed that all BU patients should be offered quality provider-initiated HIV testing and counselling. In areas with high prevalence of malaria and/or bacterial infections, all patients with HIV co-infection should be started on cotrimoxazole preventative therapy. Combination antibiotic treatment for BU should be commenced before starting antiretroviral therapy (ART) and provided for 8 weeks duration. The suggested combination is rifampicin (10 mg/kg daily up to a maximum of 600 mg/day) plus streptomycin (15 mg/kg daily). An alternative regimen is rifampicin plus clarithromycin (7.5 mg/kg twice daily up to a maximum of 1000 mg daily) although due to drug interactions with antiretroviral drugs this regimen should be used with caution. ART should be initiated in all BU-HIV co-infected patients with symptomatic HIV disease (WHO clinical stage 3 or 4) regardless of CD4 cell count and in asymptomatic individuals with CD4 count ≤500 cells/mm(3) . If CD4 count is not available, BU-HIV co-infected individuals with category 2 or 3 BU disease should be offered ART. For eligible individuals, ART should be commenced as soon as possible within 8 weeks after commencing BU treatment, and as a priority in those with advanced HIV disease (CD4 ≤ 350 cells/mm(3) or WHO stage 3 or 4 disease). All co-infected patients should be actively screened for tuberculosis before commencing BU treatment and before starting ART. Programmes should implement a monitoring and reporting system to document the outcomes of BU-HIV interventions. CONCLUSIONS: Knowledge of the clinical and epidemiological interactions between BU and HIV disease is limited. While awaiting more urgently needed evidence, current management practice of both diseases has been useful to build simple 'common sense' preliminary guidance on how to manage BU-HIV co-infection.

In the case of transmission of Mycobacterium ulcerans in buruli ulcer disease Acanthamoeba species stand accused.

Buruli ulcer disease caused by Mycobacterium ulcerans results in extensive destruction of skin and soft tissue and long-term functional disabilities that ultimately require surgery and rehabilitation. The disease is associated with aquatic and swampy environments with the mycobacterium occurring in biofilms, soil, aquatic insects, fish and wildlife however, the mode of transmission to humans remains an enigma. Current transmission ideas including bites from predatory water bugs and mosquitoes, do not explain satisfactorily the spasmodic disease distribution in human populations. Here we argue that Acanthamoeba species are the natural hosts of M. ulcerans and are mainly responsible for disease transmission because; (i) Acanthamoebae are known natural hosts of several microbial pathogens including M. marinum, M. avium and Legionella pneumophila, (ii) culture of slow-to-grow microbial pathogens hosted in nature by Acanthamoeba spp is enhanced when the media is seeded with the protozoa, (iii) acanthamoebae and M. ulcerans share similar bio-ecological and epidemiological settings, (iv) documented evidence that prior growth of L. pneumophila and M. avium in acanthamoebae influences entry mechanisms, intracellular growth and virulence in human monocytes, (v) Acanthamoeba spp also infect humans and cause diseases via routes of openings including broken skin and sites of trauma similar to M. ulcerans and (vi) M. ulcerans is rather a fastidious intracellular organism as recent analysis of the genome indicate. We argue further that temperature plays a significant role in transmission determining the fate of either the intracellular microbe or the host cells. Also, Acanthamoeba-pathogen association has a long evolutionary history because the same set of bacterial genes and gene products e.g. in L. pneumophila are required for survival in both mammalian and protozoan host cells. We suggest that the involvement of Acanthamoeba in the transmission of M. ulcerans to humans better explains the disease's epidemiology.

Sensitivity of PCR targeting Mycobacterium ulcerans by use of fine-needle aspirates for diagnosis of Buruli ulcer.

In a previous study, we reported that the sensitivity of PCR targeting the IS2404 insertion sequence of Mycobacterium ulcerans was 98% when it was applied to 4-mm punch biopsy samples of Buruli lesions. Fine-needle aspiration (FNA) is a less traumatic sampling technique for nonulcerated lesions, and we have studied the sensitivity of PCR using FNA samples. Fine-needle aspirates were taken with a 21-gauge needle from 43 patients diagnosed clinically with M. ulcerans disease. Four-millimeter punch biopsies were obtained for microscopy, culture, and PCR targeting the IS2404 insertion sequence. The sensitivity of PCR using samples obtained by FNA was 86% (95% confidence interval [95% CI], 72 to 94%) compared with that for PCR using punch biopsy samples. In this study, the sensitivities of culture and microscopy for punch biopsy samples were 44% (95% CI, 29 to 60%) and 26% (95% CI, 14 to 41%), respectively. This demonstrates that PCR on an FNA sample is a viable minimally invasive technique to diagnose M. ulcerans lesions.

Removal of colour from a kraft pulp and paper mill effluent in Kenya using a combination of electrochemical method and phosphate rock.

A study was undertaken to remove colour from a kraft mill's treated effluent in Kenya and determine the suitability of phosphate rock to replace wood ash during the electrochemical process. The electrochemical method alone, electrochemical combined with alum (ELCAL), wood ash leachate (ELCAS) and phosphate rock (ELPHOS) solutions at a rate of 165 to 1000 g/m3 were tested. Effluent characteristics were determined after complete removal of colour. Same reduction rates of TS (85%) and TSS (89%) were recorded by ELCAS and ELPHOS. However, ELPHOS removed more COD (86 to 91%) and more BOD (85 to 92%) than ELCAS. Furthermore, the pH of ELPHOS treated solution was 9.3, within the Kenya Local Government's allowable limit. Power reduction with ELCAS and ELPHOS varied between 53 to 73% and 49 to 69% respectively but the difference was not statistically significant. Overnight aeration further improved the quality of ELCAS and ELPHOS treated effluent, reducing BOD and COD values to 0 mg/l. ELPHOS cost ($0.29/m3) was nevertheless three times higher than that of ELCAS ($0.10/m3), mainly because of free wood ash. ELPHOS did not also increase effluent phosphorus. It was therefore recommended that various ways be explored in making ELPHOS more economical to replace ELCAS.

Efficacy of the combination rifampin-streptomycin in preventing growth of Mycobacterium ulcerans in early lesions of Buruli ulcer in humans.

Mycobacterium ulcerans disease is common in some humid tropical areas, particularly in parts of West Africa, and current management is by surgical excision of skin lesions ranging from early nodules to extensive ulcers (Buruli ulcer). Antibiotic therapy would be more accessible to patients in areas of Buruli ulcer endemicity. We report a study of the efficacy of antibiotics in converting early lesions (nodules and plaques) from culture positive to culture negative. Lesions were excised either immediately or after treatment with rifampin orally at 10 mg/kg of body weight and streptomycin intramuscularly at 15 mg/kg of body weight daily for 2, 4, 8, or 12 weeks and examined by quantitative bacterial culture, PCR, and histopathology for M. ulcerans. Lesions were measured during treatment. Five lesions excised without antibiotic treatment and five lesions treated with antibiotics for 2 weeks were culture positive, whereas three lesions treated for 4 weeks, five treated for 8 weeks, and three treated for 12 weeks were culture negative. No lesions became enlarged during antibiotic treatment, and most became smaller. Treatment with rifampin and streptomycin for 4 weeks or more inhibited growth of M. ulcerans in human tissue, and it provides a basis for proceeding to a trial of antibiotic therapy as an alternative to surgery for early M. ulcerans disease.

Clinico-histopathological findings of Buruli ulcer.

Here, we report the clinico-pathological findings of Buruli ulcer. The patients were 2 females, 9 and 23 years of age and one male, 47 years of age from the Ashanti Country of Ghana. Clinically, cutaneous lesions were classified as nodular, ulcero-nodular and ulcerative. Histopathologically, lesions involved cutaneous and subcutaneous tissue, which showed lympho-epithelioid cell proliferation and panniculitis with characteristic fat necrotic changes. Vascular inflammation, with the nerve tissue involvement, are prominent features on the chronological spectrum of the 3 cases. In all but the early case, Mycobacterium ulcerans could be visualized from the mid dermal area to the subcutis by Fite-Faraco and Harada stain. The ulcerated lesions were also immunoreactive to phenolic glycolipid-1 (PGL-1). These findings suggest Mycobacterium ulcerans infection with lesions of different ages. Further, we also show the need to identify distinct characteristics for differential diagnosis with lesions caused by other mycobacteria.

Mycobacterium ulcerans infection.

After tuberculosis and leprosy, Buruli-ulcer disease (caused by infection with Mycobacterium ulcerans) is the third most common mycobacterial disease in immunocompetent people. Countries in which the disease is endemic have been identified, predominantly in areas of tropical rain forest; the emergence of Buruli-ulcer disease in West African countries over the past decade has been dramatic. Current evidence suggests that the infection is transmitted through abraded skin or mild traumatic injuries after contact with contaminated water, soil, or vegetation; there is one unconfirmed preliminary report on possible transmission by insects. The clinical picture ranges from a painless nodule to large, undermined ulcerative lesions that heal spontaneously but slowly. Most patients are children. The disease is accompanied by remarkably few systemic symptoms, but occasionally secondary infections resulting in sepsis or tetanus cause severe systemic disease and death. Extensive scarring can lead to contractures of the limbs, blindness, and other adverse sequelae, which impose a substantial health and economic burden. Treatment is still primarily surgical, and includes excision, skin grafting, or both. Although BCG has a mild but significant protective effect, new vaccine developments directed at the toxins produced by M. ulcerans are warranted. In West Africa, affected populations are underprivileged, and the economic burden imposed by Buruli-ulcer disease is daunting. Combined efforts to improve treatment, prevention, control, and research strategies (overseen by the WHO and funded by international relief agencies) are urgently needed.

PIP: This paper focuses on Buruli-ulcer disease, the third most common mycobacterial disease among immunocompetent people. Buruli-ulcer disease is caused by an infection with Mycobacterium ulcerans, which belongs to the large group of environmental mycobacteria. It is endemic in many countries, usually in areas of tropical rain forest. Transmission of infection is through abraded skin or mild traumatic injuries after contact with contaminated water, soil, or vegetation. This disease mostly affects children which manifest from painless nodules to large, undermined ulcerative lesions that heals spontaneously but slowly. Buruli-ulcer disease is accompanied by few systemic symptoms, but occasionally secondary infections resulting in sepsis or tetanus cause severe systemic disease and death. However, extensive scarring can lead to contractures of the limbs, blindness, and other adverse complications. Management of the disease is still primarily surgical, and includes excision, skin grafting, or both. Although Bacillus Calmette-Guerin vaccine has mild but a significant protective effect, vaccine developments directed at the toxin produced by M. ulcerans are needed.

Socioeconomic implications of Buruli ulcer in Ghana: a three-year review.

This study examines some of the socioeconomic cost of treating 102 cases of Buruli ulcer between 1994 and 1996 at the St. Martin's Catholic Hospital in Agroyesum in the Amansie West district of the Ashanti region of Ghana. Seventy percent of the cases were children (up to 15 years of age). There was no sex difference in the distribution of cases. Hospitalization was prolonged (average = 186 days in 1994, 103 days in 1995, and 102 days in 1996) with no significant age and sex differences. There were 10 limb amputations, 12 patients were left with contracture deformities, one patient lost sight in one eye, and two died of sepsis and tetanus. The average total treatment cost per patient was $966.85 (62% indirect) in 1994, $706.08 (75% indirect) in 1995, and $658.74 (79% indirect) in 1996. With increasing number of cases, high treatment costs, and serious complications, urgent attention should be given to the disease in terms of control and research efforts aimed at early detection and treatment.