Zufferey J, Sugar A, Rudaz P, Bille J, Glauser M P, Chave J P
Institute of Microbiology, Centre Hospitalier Universitaire Vaudois, Lausanne, Switzerland.
Eur J Clin Microbiol Infect Dis. 1993 Aug;12(8):591-5. doi: 10.1007/BF01973636.
The seroprevalence of latent Toxoplasma gondii infection was determined in a cohort of 715 HIV-positive patients followed up at an HIV outpatient clinic. Using indirect immunofluorescence and direct agglutination assays for detecting IgG, the prevalence of anti-Toxoplasma gondii antibodies was shown to be 50%. During a four-year period, clinically apparent acute toxoplasmosis occurred in 47 patients (43 with cerebral, 3 with ocular and 1 with bone marrow toxoplasmosis) among the 360 patients positive for anti-Toxoplasma gondii IgG and in one patient (with cerebral toxoplasmosis) among the 355 patients who were serologically negative. A significant rise in IgG levels could be shown during acute toxoplasmosis episodes in only 30% of patients, compared with 3% of patients without active toxoplasmosis. During acute toxoplasmosis, IgM antibodies were detected in only two patients (6%) by an immunosorbent agglutination assay and in one (3%) by an enzymatic immunocapture assay. Specific IgA was detected by a non-enzymatic immunocapture assay in six patients (18%) during acute episodes. The very high predictive value (99.7%) of a negative IgG test remains the best serological parameter for excluding an acute episode of toxoplasmosis in HIV-positive patients.
在一家HIV门诊随访的715名HIV阳性患者队列中，确定了潜伏性弓形虫感染的血清阳性率。使用间接免疫荧光法和直接凝集试验检测IgG，结果显示抗弓形虫抗体的阳性率为50%。在四年期间，360名抗弓形虫IgG阳性患者中有47名发生了临床明显的急性弓形虫病（43例脑部感染、3例眼部感染和1例骨髓弓形虫病），355名血清学阴性患者中有1名（脑部弓形虫病）发生了急性弓形虫病。与无活动性弓形虫病的患者相比，仅30%的急性弓形虫病发作患者在发作期间IgG水平有显著升高，而无活动性弓形虫病的患者这一比例为3%。在急性弓形虫病期间，通过免疫吸附凝集试验仅在2名患者（6%）中检测到IgM抗体，通过酶免疫捕获试验在1名患者（3%）中检测到IgM抗体。在急性发作期间，通过非酶免疫捕获试验在6名患者（18%）中检测到特异性IgA。IgG检测阴性的预测价值非常高（99.�%），仍然是排除HIV阳性患者急性弓形虫病发作的最佳血清学参数。
