Clinicopathological characteristics of 3 probable pediatric cases with acute severe hepatitis of unknown aetiology.

BACKGROUND

Acute severe hepatitis with unknown aetiology in children (ASHep-UA) has become a global health alert. This article reported clinicopathological characteristics of 3 probable ASHep-UA cases.

METHODS

We respectively collected serological data and liver biopsies of 3 suspected cases of ASHep-UA. Neutralizing antibodies titer for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron variants were determined by virus neutralization test (VNT). Histological assessment, immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH) for cytomegalovirus (CMV), Epstein-Barr virus (EBV), human adenoviruses (HAdV), adeno-associated virus (AAV2), human herpes virus type 6 (HHV-6) were performed to identify possible aetiologies.

RESULTS

Remarkable elevation of transaminase (median ALT level, 1100 IU/liter; median AST level, 500 IU/liter) were revealed with undetectable hepatitis A-E and non-hepatotropic virus in both sera and tissues. Weakness, jaundice, pale stools and splenomegaly were observed. Interestingly, two individuals had SARS-CoV-2 Omicron variants infection. Histologically, moderate or severe lobular necroinflammation, active interface hepatitis and portal inflammatory infiltrate with lymphocytic, plasma cells, neutrophils and eosinophilic cells were noted.

CONCLUSIONS

The exact aetiology of ASHep-UA was still unknown. By reporting the 3 probable cases, we expect to enrich the clinical experience in diagnosis and treatment of ASHep-UA as well as the pathological characteristics.