Parija Subhash Chandra, Garg Atul, Pushpa K, Khairnar Krishna, Priya T
Department of Microbiology, Jawaharlal Institute of Postgraduate Medical Education and Research, Puducherry 605006, India.
Indian J Gastroenterol. 2010 Jul;29(4):140-2. doi: 10.1007/s12664-010-0033-0. Epub 2010 Sep 3.
Stool microscopy, the commonly used test for diagnosis of intestinal amebiasis, is unreliable as it does not differentiate Entamoeba histolytica, the causative agent for amebiasis, from non-pathogenic Entamoeba dispar and Entamoeba moshkovskii.
Two hundred and forty-six stool samples collected between January to February 2009, were examined microscopically for E. histolytica/E. dispar/E. moshkovskii complex cysts and trophozoites. Nested multiplex PCR targeting a 16 S-like rRNA gene for differential detection of all the three morphologically similar forms of E. histolytica, E. moshkovskii and E. dispar simultaneously was done on all microscopy positive stool samples.
Forty-nine stool samples were positive for Entamoeba spp. by microscopy. Nested multiplex PCR for E. histolytica, E. moshkovskii and E. dispar was positive in only 19 of these samples, and only 6 of the 19 samples were positive for E. histolytica.
Stool microscopy grossly over-diagnosed intestinal amebiasis and is likely to result in unnecessary treatment with anti-protozoal drugs.
粪便显微镜检查是诊断肠道阿米巴病常用的检测方法，但该方法不可靠，因为它无法区分引起阿米巴病的溶组织内阿米巴与非致病性的迪斯帕内阿米巴和莫氏内阿米巴。
对2009年1月至2月期间收集的246份粪便样本进行显微镜检查，以检测溶组织内阿米巴/迪斯帕内阿米巴/莫氏内阿米巴复合体的包囊和滋养体。对所有显微镜检查呈阳性的粪便样本进行巢式多重PCR，该方法靶向一个类16S rRNA基因，可同时对形态相似的溶组织内阿米巴、莫氏内阿米巴和迪斯帕内阿米巴三种类型进行鉴别检测。
通过显微镜检查，49份粪便样本的内阿米巴属呈阳性。在这些样本中，只有19份样本的溶组织内阿米巴、莫氏内阿米巴和迪斯帕内阿米巴巢式多重PCR呈阳性，且这19份样本中只有6份溶组织内阿米巴呈阳性。
粪便显微镜检查严重高估了肠道阿米巴病的诊断率，很可能导致不必要的抗寄生虫药物治疗。
