Laboratory of Medical Mycology, Universidad Miguel Hernández, Avenida Santiago Ramón y Cajal s/n, Edificio Muhammad Al Shafra, Sant Joan d'Alacant, Spain.
Alicante Institute for Health and Biomedical Research (ISABIAL), Alicante, Spain.
PLoS Negl Trop Dis. 2023 Aug 14;17(8):e0011327. doi: 10.1371/journal.pntd.0011327. eCollection 2023 Aug.
Mycetoma is one of the six Neglected Tropical Diseases that are prevalent in Turkana County (northwest Kenya). The aim of the study was to estimate the prevalence of mycetoma in the county, as well as to describe the main causative agents involved in the disease using methods affordable locally. Based on the data collected by the team of cooperative medicine Cirugia en Turkana (Surgery in Turkana), a specific study for mycetoma was started during the 16th humanitarian medicine campaign in February 2019. Patients with suspected mycetoma were studied at the Lodwar County Referral Hospital (LCRH). After informing the patient and getting their consent, the lesions were examined and sampled (mainly by biopsy) and clinical data were recorded. Samples were washed in sterile saline solution and cut in fragments. Some of these were inoculated on Sabouraud Dextrose Agar, Malt Extract Agar, and diluted Nutrient Agar plates. One fragment of each sample was used for DNA extraction. The DNA and the rest of the fragments of samples were kept at -20°C. All cultures were incubated at room temperature at the LCRH laboratory. The DNA obtained from clinical samples was submitted to PCR amplification of the ITS-5.8S and the V4-V5 16S rRNA gene region, for the detection and identification of fungi and bacteria respectively. From February 2019 till February 2022, 60 patients were studied. Most of them were men (43, 74,1%) between 13 and 78 y.o. (mean age 37). Half of the patients were herdsmen but, among women 40% (6) were housewives and 26.7% (4) charcoal burners. Lesions were mainly located at the feet (87.9%) and most of the patients (54; 93.1%) reported discharge of grains in the exudate, being 27 (46.6%) yellow or pale colored and 19 (32.8%) of them dark grains. Culture of clinical samples yielded 35 fungal and bacterial putative causative agents. Culture and molecular methods allowed the identification of a total of 21 causative agents of mycetoma (39.6% of cases studied). Most of them (17) corresponded to fungi causing eumycetoma (80.9%) being the most prevalent the genus Madurella (7; 41.2%), with two species involved (M. mycetomatis and M. fahalii), followed by Aspergillus (2; 11.8%). Other minority genera detected were Cladosporium, Fusarium, Acremonium, Penicillium, and Trichophyton (5.9% each of them). Actinobacteria were detected in 19.1% of samples, but only Streptomyces somaliensis was identified as a known agent of mycetoma, the rest being actinobacteria not previously described as causative agents of the disease, such as Cellulosimicrobium cellulans detected in two of the patients. Although Kenya is geographically located in the mycetoma belt, to our knowledge this is the first report on mycetoma in this country from 1973, and the first one for Turkana County.
足菌肿是在肯尼亚图尔卡纳县(西北部)流行的六种被忽视热带病之一。本研究的目的是评估该县足菌肿的流行情况,并使用当地负担得起的方法描述参与该疾病的主要病原体。根据合作医学 Cirugia en Turkana(图尔卡纳外科手术)团队收集的数据,2019 年 2 月第 16 次人道主义医学运动期间开始了一项专门针对足菌肿的研究。在洛德瓦尔县转诊医院(LCRH)对疑似患有足菌肿的患者进行了研究。在告知患者并获得其同意后,对病变进行了检查和取样(主要通过活检),并记录了临床数据。将样本在无菌生理盐水溶液中洗涤并切成碎片。将这些样本中的一些接种到萨布罗琼脂、麦芽提取物琼脂和稀释营养琼脂平板上。每个样本的一个片段用于 DNA 提取。将 DNA 和样本的其余部分保存在-20°C。所有培养物均在 LCRH 实验室在室温下孵育。从临床样本中获得的 DNA 被提交用于 ITS-5.8S 和 V4-V5 16S rRNA 基因区域的 PCR 扩增,分别用于真菌和细菌的检测和鉴定。从 2019 年 2 月到 2022 年 2 月,共研究了 60 名患者。他们大多是 13 至 78 岁(平均年龄 37 岁)的男性(43 人,占 74.1%)。一半的患者是牧民,但在女性中,有 40%(6 人)是家庭主妇,26.7%(4 人)是木炭工人。病变主要位于脚部(87.9%),大多数患者(54 人;93.1%)报告渗出物中有谷物排出,其中 27 人(46.6%)的谷物呈黄色或淡色,19 人(32.8%)的谷物呈深色。临床样本的培养产生了 35 种真菌和细菌推定病原体。培养和分子方法总共鉴定出 21 种足菌肿的病原体(研究病例的 39.6%)。其中大多数(17)是引起真真菌肿的病原体(80.9%),最常见的是 Madurella 属(7;41.2%),涉及两种物种(M. mycetomatis 和 M. fahalii),其次是曲霉属(2;11.8%)。检测到的其他少数属包括枝孢菌属、镰孢菌属、枝顶孢属、青霉属和毛癣菌属(各占 5.9%)。在 19.1%的样本中检测到放线菌,但仅鉴定出链霉菌索马里亚种是一种已知的足菌肿病原体,其余为以前未被描述为该疾病病原体的放线菌,例如在两名患者中检测到的纤维单胞菌属纤维素。尽管肯尼亚在地理位置上位于足菌肿带,但据我们所知,这是自 1973 年以来肯尼亚首次报告该病,也是图尔卡纳县的首次报告。