Hepatitis E Virus Capsid Antigen (HEV-Ag) – A practical diagnostic biomarker in the HEV outbreak scenario

Wang

Front. Cell. Infect. Microbiol.

et al. 2023

Hepatitis E virus (HEV) is a common cause of acute hepatitis that threatens human health worldwide. With the popularization of detection technology, the reports of hepatitis E have gradually increased. Here, we present a rare case of co-infection with hepatitis E viruses, Clonorchis sinensis and Escherichia coli. A 52-year-old man was hospitalized because of fatigue, jaundice, and nausea for more than 2 weeks. Laboratory tests showed elevated bilirubin, aminotransferase (ALT), and aspartate aminotransferase (AST); HEV-IgM was positive, and HEV-RNA could be detected. Moreover, parasites were found in the biliary drainage and the biliary culture, which suggested Escherichia coli. The patient was effectively treated with praziquantel, imipenem, and hepatoprotective drugs and his clinical symptoms were relieved after 2 months; total bilirubin decreased to 85.1 μmol/L, ALT decreased to 92.4 U/L, and AST decreased to 102 U/L.

Section: Discussionmentioning

confidence: 99%

Co-infection of hepatitis E virus, Clonorchis sinensis, and Escherichia coli: A case report

Wang

Front. Cell. Infect. Microbiol.

et al. 2023

“…[3,4] The commercial Ag detection kit targets both ORF2 S and ORF2 C , which contributes to the high sensitivity of serum HEV Ag kits that rivals the sensitivity of RNA testing in diagnosing HE. This Ag kit targeting serum ORF2 S has been used in clinical and laboratory studies [17][18][19][20] and has also been recommended for the diagnosis of acute and chronic HEV infection by the European Association for the Study of the Liver. [21] Nevertheless, level of HEV Ag in urine is 80 times higher than in serum, especially in acute HE patients (Figure S8).…”

Section: Discussionmentioning

confidence: 99%

Urine is a viral antigen reservoir in hepatitis E virus infection

Dong

Tian

et al. 2022

Hepatology

Background and Aims: HEV ORF2 antigen (Ag) in serum has become a tool for diagnosing current HEV infection. Particularly, urinary shedding of HEV Ag has been gaining increasing interest. We aim to uncover the origin, antigenicity, diagnostic performance, and diagnostic significance of Ag in urine in HEV infection.Approach and Results: Clinical serum and urine samples from patients with acute and chronic HEV infection were analyzed for their Ag levels. Ag in urine was analyzed by biochemical and proteomic approaches. The origin of urinary Ag and Ag kinetics during HEV infection was investigated in mouse and rabbit models, respectively. We found that both the Ag level and diagnostic sensitivity in urine were higher than in serum. Antigenic protein in urine was an E2slike dimer spanning amino acids 453-606. pORF2 entered urine from serum in mice i.v. injected with pORF2. Ag in urine originated from the secreted form of pORF2 (ORF2 S ) that abundantly existed in hepatitis E patients' serum. HEV Ag was specifically taken up by renal cells and was disposed into urine, during which the level of Ag was concentrated >10-fold, resulting in the higher diagnosing sensitivity of urine Ag than serum Ag. Moreover, Ag in urine appeared 6 days earlier, lasted longer than viremia and antigenemia, and showed good concordance with fecal RNA in a rabbit model.

Current Opinion in Gastroenterology

“…Stool shedding of virus persists longer, but most clinical laboratories will not accept stool specimens. In resource-limited settings during an HEV outbreak, testing for anti-HEV IgM or HEV capsid antigen in serum samples can be performed with rapid field tests [10 ▪ ,27,28].…”

Section: Diagnosis Of Infection With Hepatitis E Virusmentioning

confidence: 99%

Hepatitis E virus: has anything changed?

Willauer¹,

Sherman

2023

Purpose of reviewInfection with hepatitis E virus (HEV) is a global health concern, yet a clinically underdiagnosed cause of acute and chronic hepatitis. The WHO estimates that 20 million people are infected with HEV annually, yet the epidemiology, diagnosis and prevention remain elusive in many clinical settings. Recent findingsOrthohepevirus A (HEV-A) genotypes 1 and 2 cause acute, self-limited hepatitis through faecal-oral transmission. In 2022, the first-ever vaccine campaign was implemented as a response to an HEV outbreak in an endemic region. HEV-A genotypes 3 and 4 are zoonotic infections that primarily cause chronic HEV infection in immunosuppressed populations. Pregnant women and immunocompromised persons are at high risk for severe illness in some settings. Another recent advance in our knowledge of HEV is the zoonotic transmission of Orthohepevirus C (HEV-C) to humans, presumably from contact with rodents and/or their excrement. Previously, HEV infection in humans was presumed to be limited to HEV-A only. SummaryClinical recognition and accurate diagnosis are essential to the management of HEV infection and understanding the global burden of the disease. Epidemiology affects clinical presentations. Targeted response strategies in HEV outbreaks are needed for the prevention of disease, and vaccine campaigns may prove to be an effective part of these strategies.