Sobieszczańska B, Grzybek-Hryncewicz K, Rudzka A
Katedry i Zakładu Mikrobiologii Akademii Medycznej we Wrocławiu.
Pol Merkur Lekarski. 1997 Nov;3(17):228-30.
The diagnosis of Toxoplasma gondii infection is currently based on immunological tests, but tests for IgM and IgG antibodies alone are often insufficient to estimate the risk of active disease, especially during pregnancy and in immunodeficient patients. Classically the study of anti-toxoplasma immunity involves titration of IgG antibodies, which reflect immunity to the parasite, and IgM antibodies which of present, reveal acute infection. However, technical advances have shown the limitations of these tests as tests for IgM can be positive because of residual specific IgM or even in subjects free of acute infection due to the existence of natural interfering IgM. In addition, IgM can be absent in children with congenital toxoplasmosis or subjects with secondary reactivation. The purpose of our study was to evaluated of IgA antibodies to T. gondii in serum samples which were positive in screening test. Our results confirm the diagnostic value of testing for anti-toxoplasma IgA antibodies. These antibodies are absent in uninfected subjects and are detected rapidly after primary infection. The determination of IgA complements IgM determination for the diagnosis of toxoplasmosis.
目前，弓形虫感染的诊断基于免疫学检测，但仅检测IgM和IgG抗体往往不足以评估活动性疾病的风险，尤其是在孕期和免疫缺陷患者中。传统上，抗弓形虫免疫研究包括滴定反映对该寄生虫免疫力的IgG抗体，以及若存在则表明急性感染的IgM抗体。然而，技术进步已显示出这些检测方法的局限性，因为IgM检测可能因残留特异性IgM而呈阳性，甚至在无急性感染的受试者中因天然干扰性IgM的存在而呈阳性。此外，先天性弓形虫病患儿或继发性再激活患者体内可能不存在IgM。我们研究的目的是评估筛查试验呈阳性的血清样本中抗弓形虫IgA抗体。我们的结果证实了检测抗弓形虫IgA抗体的诊断价值。这些抗体在未感染的受试者中不存在，在初次感染后可迅速检测到。IgA的测定补充了IgM的测定，用于弓形虫病的诊断。
