Severe acute hepatitis of unknown causes in children - Current findings, questions, opinions, and recommendations, a mini-review

Since October 2021 in Alabama, the United States, and March 2022 in central Scotland, the United Kingdom, the number of cases of severe acute hepatitis of unknown etiology/causes in children was found to increase, and the total number of cases has reached 920 worldwide by June 22 this year, 45 cases (5%) required liver transplantation, and 18 cases (2%) died according to World Health Organization (WHO). To understand the basic characteristics of this disease/syndrome, a literature search was performed at PubMed, websites of WHO, UK Health Security Agency, and US and European Centers for Disease Control and Prevention, and more than 20 reports were enrolled as references for this review. The main clinical manifestations are anorexia, vomiting, fatigue, jaundice, and so forth. Most of the cases seemed to have a self-limited course of the disease, about 6% of cases may develop life-threatening acute liver failure. The disease seems to be transmissible from person to person. Human adenovirus was detected in up to 75% of cases, but this virus seems not to be the only and major etiologic agent, other cofactors probably are involved. Researchers proposed many hypotheses concerning the etiology and pathogenesis, and many important works and studies are ongoing. This mini-review is aimed at summarizing, reviewing, and further understanding the characteristics of the disease, raising some clinically relevant questions, and trying to discuss some questions that may be related to the treatment of the disease for consideration.