HIV合并人芽囊原虫和蓝氏贾第鞭毛虫感染1例

HIV co-infection with Blastocystis hominis and Giardia lamblia in a patient

患者,女,64岁,农民,以“腰部间断性疼痛不适”入院。患者人类免疫缺陷病毒(HIV)抗原/抗体检测结果为阳性,粪样常规生理盐水涂片显微镜镜检检出人芽囊原虫和蓝氏贾第鞭毛虫包囊,人芽囊原虫包囊呈圆形、卵圆形,大小不一,1~2颗颗粒状核;碘液染色虫体中间有空泡,在空泡与胞膜之间有不规则、闪亮、似月牙状的边缘,其内见多个小亮点;蓝氏贾第鞭毛虫包囊呈椭圆形,囊壁较厚,与虫体间有明显的间隙,碘液染色囊内轴柱明显,可见2~4个核,核位于轴柱两侧,苏木素染色后包囊内可见明显的4个紫红色的核。巢式PCR从患者粪样DNA中扩增出511 bp的条带,与蓝氏贾第鞭毛虫基因序列TSA417(GenBank登录号AF065606)的一致性为99%;用人芽囊原虫BhRDr和RD5特异引物PCR扩增核糖体小亚基基因,扩增出约600 bp的条带,测序结果为人芽囊原虫ST1型。结合患者饮生水史、使用非水冲式厕所、饲养猫、犬等流行病学史,诊断为HIV合并人芽囊原虫和蓝氏贾第鞭毛虫混合感染。给予甲硝唑(0.2 g/次,3次/d)治疗4 d后,患者症状缓解并出院。

A 64-year-old female patient,who is a farmer,was admitted to the hospital for intermittent pain and discomfort in the lower back.The patient was positive for human immunodeficiency virus(HIV) antigen/antibody test.Blastocystis hominis and Giardia lamblia flagellate cysts were found by microscopic examination for the normal saline smear of the fecal sample.The B.hominis cysts were round,oval,and varying in size,with 1 to 2 granular nuclei.Vacuoles were seen in the middle of the iodine-stained parasites with irregular,shiny,crescent-like edges between the vacuoles and the cell membrane.Many small bright spots were seen in the vacuoles.The G.lamblia flagellate cysts are oval in shape,with thick cyst walls.There is a clear gap between the cyst and the parasite.The iodine stains the inner axis of the cyst with 2 to 4 nuclei.The nuclei are located on both sides of the axis.Four purplish red nuclei were evident in the cyst after hematoxylin staining.Nested PCR amplified a 511 bp band from patient fecal DNA,which was 99% identical to the sequence TSA417 of G.lamblia(GenBank accession number AF065606).The ribosomal small subunit gene was amplified by PCR with the specific primers of BhRDr and RD5 of B.hominis,and a band of approximately 600 bp was amplified.The sequencing suggested it was B.hominis ST1type.Combined with the patient’s epidemiological history of drinking unboiled water,using dry-toilet,breading cats and dogs,etc.,the diagnosis of HIV co-infection with B.hominis and G.lamblia was made.After 4 days of treatment with metronidazole(0.2 g/time,3 times/d),the patient ’s symptoms were relieved,and the patient was discharged.