Cryptococcosis in Atlántico, Colombia: an approximation of the prevalence of this mycosis and the distribution of the etiological agent in the environment

ABSTRACTINTRODUCTION:Cryptococcosis is an invasive disease acquired by inhalation of infectious propagules from the environment. Currently, compulsory notification of the spread of this disease is not required in Colombia. However, reporting of human immunodeficiency virus (HIV)/acquired immune deficiency syndrome cases to the National Surveillance System has suggested that there is a growing population at risk of contracting cryptococcosis. Few studies have described the occurrence of cryptococcosis in Colombia. Therefore, in this study, we examined the pathology of this disease in Atlántico, Colombia and determined the distributions of Cryptococcus neoformans and Cryptococcus gattii in the environment.METHODS:Clinical samples/isolates were gathered from cases of cryptococcosis previously diagnosed at health institutions in Atlántico, and surveys were completed by clinicians. The environmental study considered 32 sampling points and three tree species, i.e., Quickstick ( Gliricidia sepium ), Almond ( Terminalia catappa ), and Pink trumpet ( Tabebuia rosea ). Environmental and clinical samples/isolates were analyzed for phenotypic and genotypic confirmation.RESULTS:From 1997-2014, 41 cases of cryptococcosis were reported. The mean patient age was 40.5 years (range: 18-63 years); 76% were men, and 78% were HIV positive. Isolation was possible in 38 cases ( C. neoformans , molecular type VNI in 37 cases and C. gattii , molecular type VGI in one case). In 2012-2014, 2,068 environmental samples were analyzed with a positivity of 0.4% ( C. neoformans , molecular type VNI) in Almond and Pink trumpet trees.CONCLUSIONS:Cryptococcus neoformans , molecular type VNI had a higher prevalence than C. gattii and was associated with human exposure and the pathogenesis of cryptococcosis in this geographical region.

引言：隐球菌病是一种经吸入环境中感染性繁殖体而感染的侵袭性疾病。目前哥伦比亚尚未要求对该病的传播实施强制报告。不过，向国家监测系统上报的人类免疫缺陷病毒（human immunodeficiency virus, HIV）/获得性免疫缺陷综合征（acquired immune deficiency syndrome, AIDS）病例数据显示，隐球菌病的易感人群规模正逐步扩大。当前针对哥伦比亚隐球菌病发病情况的研究较为匮乏。因此，本研究对哥伦比亚大西洋省的隐球菌病病理特征展开分析，并明确了新型隐球菌（Cryptococcus neoformans）与格特隐球菌（Cryptococcus gattii）在环境中的分布情况。
方法：研究收集了此前在大西洋省各医疗机构确诊的隐球菌病病例的临床样本与分离株，并由临床医生完成了相关调研。环境研究共设置32个采样点，涵盖3个树种，即速生槐（Gliricidia sepium）、扁桃树（Terminalia catappa）与粉花风铃木（Tabebuia rosea）。对环境样本与临床样本/分离株进行表型与基因型鉴定。
结果：1997年至2014年间，共报告41例隐球菌病病例。患者平均年龄为40.5岁（范围：18~63岁）；76%为男性，78%为HIV阳性。38例病例成功分离到菌株，其中37例为新型隐球菌分子型VNI，1例为格特隐球菌分子型VGI。2012年至2014年间，共分析2068份环境样本，阳性率为0.4%，阳性菌株均为新型隐球菌分子型VNI，分离自扁桃树与粉花风铃木。
结论：在该地理区域内，新型隐球菌分子型VNI的流行率高于格特隐球菌，且与人类暴露及隐球菌病的发病机制密切相关。