# A Preliminary Study on Clinical Characteristics of Patients With Autoimmune Liver Following Coronavirus Disease 2019

## TL;DR

This study explores how autoimmune liver disease can develop after a COVID-19 infection and compares its features to typical autoimmune liver disease.

## Contribution

The study identifies unique clinical features of autoimmune liver disease following COVID-19, distinguishing it from typical cases.

## Key findings

- Post-COVID-19 autoimmune liver disease patients had lower age and calcium levels compared to typical autoimmune liver disease patients.
- Post-COVID-19 autoimmune liver disease patients showed higher IgM levels and a higher percentage of ANA positivity.
- The condition shares typical autoimmune liver disease features like acute onset but has distinguishing characteristics.

## Abstract

This study aimed to investigate the clinical features of patients with autoimmune liver disease (AILD) following coronavirus disease 2019 (COVID-19).

For the AILD group, 19 inpatients who were first diagnosed with AILD were enrolled from Wuxi Fifth People's Hospital between January 2021 and December 2021. The post-COVID-19 AILD group comprised seven patients recruited after December 2022 who were initially diagnosed with COVID-19 and later diagnosed with AILD. Routine blood indices, biochemical parameters, serum-related antibodies, and serum immunoglobulin levels were assessed in the two groups. Ultrasound-guided liver biopsy was performed to observe the pathological characteristics of the liver in the two groups. The expression of immune indices in the two groups was observed by immunohistochemistry.

The age and calcium levels of the post-COVID-19 AILD patients were significantly lower than those of the AILD patients (p < 0.05). The IgM levels were significantly higher in the post-COVID-19 AILD group than in the AILD group (p < 0.05). No significant differences in the other routine blood and blood biochemical indices were present between the two groups. The antinuclear antibody (ANA) and SM antibody levels were compared, revealing a significantly higher percentage of ANA positivity among post-COVID-19 AILD patients than AILD patients (p < 0.05).

AILD following COVID-19 has typical AILD characteristics, including acute onset, but has other characteristics that allow it to be distinguished from other AILDs.