Vinayak V K, Kumar P, Punj V, Vashist N, Kanwar J R, Bhasin D K, Singh K
Department of Experimental Medicine, Postgraduate Institute of Medical Education and Research, Chandigarh.
Indian J Gastroenterol. 1993 Jul;12(3):77-9.
Stool microscopy, the conventional method of diagnosing intestinal amebiasis, fails to detect Entamoeba histolytica in more than 30-40% of clinically suspected cases. Demonstration of parasite products in clinical specimens has been suggested as an alternative. However, the usefulness of demonstrating amebic antigen in the stools of clinical cases needs to be assessed.
A double-antibody sandwich enzyme linked immunosorbent assay (ELISA) using anti-trophozoite antibodies to capture E histolytica specific coproantigen(s) was carried out on stools obtained from 31 patients with microscopically confirmed non-dysenteric amebic colitis, 18 patients with intestinal parasites other than E histolytica and 41 apparently healthy subjects.
The assay detected E histolytica specific coproantigen(s) in stools of 23 (74.2%) of 31 subjects with non-dysenteric amebic colitis, none of 18 with other parasitic infections and 1 (2.4%) of 41 apparently healthy subjects.
Our results provide evidence for the presence of E histolytica specific coproantigen(s) in stool eluates from patients with amebic infection; this finding can be exploited for confirming ongoing amebic infection. However, the sensitivity of the assay needs to be improved by the use of relevant monospecific/monoclonal antibodies.
粪便显微镜检查是诊断肠道阿米巴病的传统方法，但在超过30%-40%的临床疑似病例中无法检测到溶组织内阿米巴。有人建议检测临床标本中的寄生虫产物作为一种替代方法。然而，需要评估在临床病例粪便中检测阿米巴抗原的实用性。
采用双抗体夹心酶联免疫吸附试验（ELISA），使用抗滋养体抗体捕获溶组织内阿米巴特异性粪抗原，对31例经显微镜确诊为非痢疾性阿米巴结肠炎的患者、18例感染除溶组织内阿米巴之外肠道寄生虫的患者以及41名明显健康的受试者的粪便进行检测。
该检测在31例非痢疾性阿米巴结肠炎患者中的23例（74.2%）粪便中检测到溶组织内阿米巴特异性粪抗原，在18例其他寄生虫感染患者的粪便中均未检测到，在41名明显健康的受试者中仅1例（2.4%）检测到。
我们的结果为阿米巴感染患者粪便洗脱液中存在溶组织内阿米巴特异性粪抗原提供了证据；这一发现可用于确认正在进行的阿米巴感染。然而，需要通过使用相关的单特异性/单克隆抗体来提高该检测的灵敏度。
