Servicio de Inmunología y Alergia, Departamento de Consulta Externa de Pediatría, Instituto Nacional de Pediatría (INP), Ciudad de México, México.
Laboratorio de Parasitología Experimental, Subdirección de Medicina Experimental, Instituto Nacional de Pediatría (INP), Ciudad de México, México.
Immun Inflamm Dis. 2021 Jun;9(2):435-442. doi: 10.1002/iid3.403. Epub 2021 Feb 8.
Toxocara canis can produce or exacerbate asthma, and the detection of anti-T. canis immunoglobulin G (IgG) does not discriminate between recent infection or active larva migrans. In this study, we searched for T. canis third-stage larval antigens (L TES) and anti-T. canis antibodies in children with different severities of asthma, controlled or uncontrolled.
A total of 145 patients with asthma who were previously diagnosed using the Global Initiative for Asthma guidelines were included. The asthma control was evaluated with the Asthma Control Questionnaire (ACQ). Enzyme-linked immunosorbent assay was performed for the detection of L TES; IgG was detected using sera preadsorbed with Ascaris antigens (native kit), and a commercial kit (IgG) was used as the gold standard.
L TES was found in 2 patients (1.37%). One had L TES and anti-T. canis IgG, suggesting active larva migrans. In the other patient, only L TES was detected, likely because an infection had begun. The seroprevalence with the commercial kit and native kit was 6.2% and 17.93%, respectively. There was no significant association among asthma severity, ACQ and T. canis seroprevalence (p > .05).
It is possible to detect L TES in patients with asthma. Two complementary techniques that can determine the infection status with T. canis and rule out cross-reactions involve the detection of L TES and IgG using sera preadsorbed with Ascaris antigen. There was no significant association among asthma severity, ACQ and T. canis seroprevalence.
犬弓首蛔虫可导致或加重哮喘，而抗犬弓首蛔虫免疫球蛋白 G（IgG）的检测并不能区分近期感染或活动性幼虫移行。在这项研究中，我们在不同严重程度（控制或未控制）的哮喘患儿中寻找犬弓首蛔虫第三期幼虫抗原（L TES）和抗犬弓首蛔虫抗体。
共纳入 145 名先前根据全球哮喘倡议指南诊断为哮喘的患者。使用哮喘控制问卷（ACQ）评估哮喘控制情况。采用酶联免疫吸附试验检测 L TES；使用预先吸附了蛔虫抗原的血清（天然试剂盒）检测 IgG，并将商业试剂盒（IgG）作为金标准。
发现 2 名患者（1.37%）存在 L TES。其中 1 名患者存在 L TES 和抗犬弓首蛔虫 IgG，提示活动性幼虫移行。另 1 名患者仅检测到 L TES，可能是因为感染刚刚开始。商业试剂盒和天然试剂盒的血清阳性率分别为 6.2%和 17.93%。哮喘严重程度、ACQ 和犬弓首蛔虫血清阳性率之间无显著相关性（p>0.05）。
可以在哮喘患者中检测到 L TES。两种可互补的技术，即检测经蛔虫抗原预先吸附的血清中的 L TES 和 IgG，可确定犬弓首蛔虫感染状况并排除交叉反应，在哮喘患儿中，检测到 L TES 与哮喘严重程度、ACQ 或犬弓首蛔虫血清阳性率无显著相关性。
