自然环境中分离出致病性自由生活阿米巴

ISOLATION OF PATHOGENIC FREE-LIVING AMOEBAE FROM NATURAL ENVIRONMENT

湘江、泳池等水源中采集样本236个,其中77.5％有自由生活阿米巴(FLA)生长,从属于9种不同类型。65个阳性样本经鼻滴注小鼠作致病试验,筛选出4个致病性FLA分离物。该分离物使部分小鼠死于阿米巴脑炎。死亡小鼠脑、鼻粘膜等组织可见棘阿米巴滋养体和包囊。进一步观察证明。此阿米巴经鼻粘膜和筛孔直接侵犯中枢神经系统,该种阿米巴初步鉴定为多噬棘阿米巴。

A cultivated method for isolation of free-living amoebae ( FLA) was conducted with samples from Xiangjiang River, warm spring water, pond, sewage of power plant and swimming pool. Out of 236 water and soil samples, 183 (77.5%) contained nine different species of FLA. Out of 183 positive samples, 65 were tested their pathogenicity in mice. A.polyphaga isolated could put 12.5-25% LACA mice and 50% outbred mice to death within 5 to 21 days when inoculated intranasally. These amoebae entered the central nervous system by the nasal mncosa to olfactory bulbs route.There were inflammatory lesions in nasal mucosa, leptomeninges and brain parenchyma.