Clinical and microbiological features of cryptococcal meningitis

Introduction In this study, the clinical features, underlying diseases and clinical outcomes of patients with cryptococcosis were investigated. In addition, a molecular analysis of the Cryptococcus neoformans species complex isolated from these patients was performed. Methods A prospective study of 62 cases of patients with cryptococcal infection was conducted at the Hospital de Doenças Tropicais de Goiás Dr. Anuar Auad from 2009-2010. Cryptococcal meningitis cases were diagnosed by direct examination and cerebrospinal fluid (CSF) sample culture. The profiling of these patients was assessed. The CSF samples were submitted to India ink preparation and cultured on Sabouraud dextrose agar, and C. neoformans was identified by the production of urease, a positive phenoloxidase test and assimilation of carbohydrates. C. neoformans and C. gattii isolates were distinguished by growth on L-canavanine-glycine-bromothymol blue medium, and molecular analysis was conducted via PCR fingerprinting reactions using M13 and (GACA)4 primers. Results From the 62 patients with cryptococcosis, 71 isolates of CSF were obtained; 67 (94.4%) isolates were identified as C. neoformans var. grubii/VNI, and 4 (5.6%) were identified as C. gattii/VGII. Of these patients, 53 had an HIV diagnosis. The incidence of cryptococcosis was higher among patients 20-40 years of age, with 74.2% of the cases reported in males. Cryptococcus-related mortality was noted in 48.4% of the patients, and the symptoms were altered sensorium, headache, fever and stiff neck. Conclusions The high morbidity and mortality observed among patients with cryptococcosis demonstrate the importance of obtaining information regarding the epidemiological profile and clinical course of the disease in the State of Goiás, Brazil.

引言 本研究旨在探究隐球菌病患者的临床特征、基础疾病与临床结局，并对从上述患者体内分离得到的新型隐球菌物种复合体（Cryptococcus neoformans species complex）开展分子生物学分析。
方法 本研究为前瞻性研究，于2009年至2010年在戈亚斯阿努尔·奥阿德博士热带病医院（Hospital de Doenças Tropicais de Goiás Dr. Anuar Auad）纳入62例隐球菌感染患者。隐球菌性脑膜炎的诊断通过直接镜检及脑脊液（cerebrospinal fluid, CSF）样本培养完成。本研究对入组患者的临床特征进行了评估。脑脊液标本经印度墨汁染色制片，并接种于沙氏葡萄糖琼脂（Sabouraud dextrose agar）培养基进行培养；通过脲酶产生试验、酚氧化酶阳性试验及碳水化合物同化试验鉴定新型隐球菌。通过L-刀豆氨酸-甘氨酸-溴百里酚蓝培养基（L-canavanine-glycine-bromothymol blue medium）上的生长特性区分新型隐球菌与格特隐球菌（Cryptococcus gattii）菌株，并采用M13引物及(GACA)4引物进行PCR指纹图谱（PCR fingerprinting）反应以完成分子生物学分析。
结果 本研究共从62例隐球菌病患者体内获得71株脑脊液分离菌株，其中67株（94.4%）鉴定为新型隐球菌格鲁比变种/VNI型，4株（5.6%）鉴定为格特隐球菌VGII型。入组患者中53例确诊HIV感染。隐球菌病的高发年龄段为20~40岁，男性患者占比达74.2%。隐球菌相关病死率为48.4%，患者常见临床症状包括意识改变、头痛、发热及颈项强直。
结论 本研究中隐球菌病患者呈现较高的发病率与病死率，提示在巴西戈亚斯州开展该疾病的流行病学特征及临床病程相关研究具有重要意义。