Castellanos Yeny Zulay, Cucunubá Zulma Milena, Flórez Astrid Carolina, Orozco-Vargas Luis Carlos
Facultad de Salud, Universidad Industrial de Santander, Bucaramanga, Colombia.
Grupo de Parasitología, Instituto Nacional de Salud, Bogotá, D.C, Colombia.
Biomedica. 2014 Apr-Jun;34(2):198-206. doi: 10.1590/S0120-41572014000200006.
The diagnosis of chronic Trypanosoma cruzi infection is supported by serological tests whose reproducibility has not been well documented.
To evaluate the reproducibility of the serological tests ELISA, IFAT and IHAT for the diagnosis of T. cruzi infection in pregnant women in an endemic zone in Santander.
Through an evaluation study of diagnostic technologies, the reproducibility of the serological tests ELISA, IFAT and IHAT was determined in serum and eluted blood from pregnant women living in an endemic area for Chagas' disease in Santander. The samples were selected by cross sectional sampling. The software Stata version 10.0 was used for statistical analysis. By means of the comparison of the highest kappa coefficient of each technique, the test with the best reproducibility was determined.
A total of 777 samples were tested. In serum, ELISA (cutoff point: 0.3), IFAT (cutoff point: 1/32) and IHAT (cutoff point: 1/16) had kappa coefficients greater than 0.8 (0.98, 95% CI: 0.93-1.00; 0.98, 95% CI: 0.92-1.00 and 0.88, 95% CI: 0.74-0.97, respectively); no statistically significant differences among the three tests were found (p> 0.05). For the blood eluates, kappa coefficients were below 0.8 (highest kappa: 0.55, 95% CI: 0.41-0.68).
For the three serological tests using serum, the reproducibility determined by the kappa coefficient was perfect. Selecting any of them is useful for the diagnosis of T. cruzi infection. Given its simplicity and cost, the ELISA test is recommended for screening for this infection.
慢性克氏锥虫感染的诊断依靠血清学检测，但这些检测的可重复性尚未得到充分记录。
评估酶联免疫吸附测定（ELISA）、间接荧光抗体试验（IFAT）和间接血凝试验（IHAT）这三种血清学检测在桑坦德一个流行地区诊断孕妇克氏锥虫感染中的可重复性。
通过一项诊断技术评估研究，在桑坦德恰加斯病流行地区的孕妇血清和洗脱血中测定ELISA、IFAT和IHAT这三种血清学检测的可重复性。样本通过横断面抽样选取。使用Stata™ 10.0软件进行统计分析。通过比较每种技术的最高kappa系数，确定可重复性最佳的检测方法。
共检测了777份样本。在血清检测中，ELISA（临界值：0.3）、IFAT（临界值：1/32）和IHAT（临界值：1/16）的kappa系数大于0.8（分别为0.98，95%置信区间：0.93 - 1.00；0.98，95%置信区间：0.92 - 1.00；0.88，95%置信区间：0.74 - 0.97）；三项检测之间未发现统计学显著差异（p > 0.05）。对于血液洗脱液，kappa系数低于0.8（最高kappa值：0.55，95%置信区间：0.41 - 0.68）。
对于使用血清的三种血清学检测，由kappa系数确定的可重复性极佳。选择其中任何一种都有助于诊断克氏锥虫感染。鉴于其简便性和成本，推荐使用ELISA检测进行这种感染的筛查。
