Dados do Trabalho

Título

Development and prototyping of rapid immunochromatographic tests for the diagnosis of hepatitis D

Introdução

It is estimated that 300 million people worldwide are infected with HBV, and that approximately 15 to 20 million of them are concomitantly infected with HDV. Although there is growing consensus that the real prevalence of hepatitis D is underestimated even in developed countries. The Amazon Basin region has one of the highest reported prevalence of HDV infection, where the population's access to laboratory diagnostic tests is still a major public health problem. Currently, the diagnosis of hepatitis D is performed through serological tests after the patient has received a positive HBsAg result. While several tests are available to diagnose hepatitis B, only a few tests for hepatitis D are available worldwide, mainly in ELISA or CLIA formats. Therefore, it is essential to develop new tests with more amenable formats for the diagnosis of hepatitis D. 

Objetivo (s)

Considering that rapid diagnostic tests (RDT) are based on an easy-to-use platform that allows diagnosis in different circumstances, we aimed to develop a prototype of a multiplex RDT capable of simultaneously detecting HBV and HDV infections. 

Material e Métodos

For this, a new recombinant antigen (DTH10.1) was designed from HDAg sequences of the eight HDV genotypes, expressed in Escherichia coli, purified by affinity chromatography. Serum samples from patients with hepatitis B (n = 195), hepatitis D (n = 198) and healthy individuals (n = 106) were used in the development of the tests, with the approval of the Ethics Committee (CEP-UFMG). First, DTH10.1 was tested in an ELISA, followed by the multiplex RDT, which was developed from the combination of two prototypes, one for detecting HBsAg, and the other for anti-HDV IgG antibodies, using a modified DTH10.1 protein. 

Resultados e Conclusão

The ELISA test using the DTH10.1 protein showed a sensitivity of 90.6% (95% CI: 84.2-94.5%) and specificity of 100% (95% CI: 94.2- 100.0%). The HBsAg RDT prototype demonstrated a sensitivity of 94.3% (95% CI: 89.5-96.98%) and a specificity of 100.0% (95% CI: 92.9-100.0%​). The anti-HDV IgG RDT showed sensitivity and specificity of 91,1% (95% CI: 80.7-96.1%) and 92.9% (95% CI: 88.0-95.9%), respectively. The multiplex RDT showed a sensitivity of 91.9% (95% CI: 83.4-96.2%) for HBsAg and 96.4% (95% CI: 87.9-99.4%) for anti-HDV IgG and a specificity of 100% (95% CI: 91.0-100.0%) and 97.8% (95% CI: 92.3-99.6%), respectively. In conclusion, the antigen and prototypes developed proved useful and are innovative tools for diagnosing HDV infection.

Palavras Chave

Hepatitis D; Hepatitis B; Serological diagnosis; ELISA; Rapid diagnostic test.