Evaluation of urinary hepatitis E virus antigen colloidal gold immunochromatographic assay in clinical diagnosis of hepatitis E virus infection.

BACKGROUND

Hepatitis E virus (HEV) is a significant public health concern worldwide. Current diagnostic methods for HEV infection have limitations in terms of accessibility and timeliness.

OBJECTIVE

To assess the diagnostic performance of the Wantai urinary HEV antigen (Ag) colloidal gold immunochromatographic assay (GICA) in HEV infection.

METHODS

This prospective study enrolled 150 patients with suspected acute hepatitis E and 50 healthy controls. Paired urine, fecal, and serum samples were collected during initial clinical evaluation. Serum and fecal HEV RNA levels were quantified via reverse transcription-quantitative polymerase chain reaction (RT-qPCR), with genotyping performed by nested RT-PCR. Serum anti-HEV IgM/IgG levels were measured by Enzyme-Linked Immunosorbent Assay (ELISA), and urinary HEV antigen was detected using GICA. Diagnostic accuracy metrics were calculated against the reference standard of HEV RNA detection.

RESULTS

HEV RNA was detected in 58 % (87/150) of suspected cases. All successfully genotyped cases (69 %, 60/87) were HEV genotype 4. All healthy controls tested negative for HEV RNA and urinary HEV Ag.The urinary HEV Ag GICA showed 98.9 % sensitivity and 87.6 % specificity, with high concordance with RT-qPCR (Kappa = 0.85). Longitudinal follow-up revealed viral clearance and liver function normalization in most patients within 3-4 weeks post-symptom onset. 85.7 % of patients achieved urinary HEV Ag negative conversion within 6-7 weeks, while anti-HEV IgM remained positive in all patients at follow-up conclusion.

CONCLUSION

Urinary HEV Ag GICA demonstrates high diagnostic reliability for acute HEV infection, offering a practical non-invasive option for resource-limited settings.