The Role of Adenovirus in Hepatitis of Unknown Etiology Among Children in Turkey, July 2022 to January 2023

Background:In the first half of 2022, the increase in cases of severe acute hepatitis in children with no epidemiological link and unknown cause has aroused concern worldwide. In this study, we aimed to determine the frequency of adenovirus in children with hepatitis of unknown origin in Turkey.Methods:In this study, which was conducted with the participation of 16 centers from Turkey, between July 2022 and January 2023, 36 pediatric patients under the age of 18 who met the definition of acute hepatitis were included.Results:Twenty (55,6%) of patients were female and 16 (44,4%) were male, with a mean age of 41.55 +/- 39.22 (3-192) months. The most common symptoms were fever (66.7%), weakness (66.7%), loss of appetite (66.7%), fatigue (61.1%), vomiting (61.1%), and diarrhea (47.2%). Six (16 %) children had acute hepatic failure. Eight of the 15 children (46%) had respiratory viral infections (rhinovirus/enterovirus, n = 4; rhinovirus + parainfluenza, n = 1; parainfluenza, n = 1, SARS-CoV-2 n = 2). Adenovirus was detected in 16 (44%) patients. Adenovirus and coinfections were detected in 7 patients. History of diarrhea and fatigue in the last month was significantly higher in the adenovirus group (P = 0.023 and 0.018). One child who had both adenovirus and rhinovirus infection required liver transplantation; all others recovered with supportive care.Conclusion:There were no deaths in our series; however, the number of cases, etiology, and severity of the clinical course may have differed between countries owing to differences in case definitions, laboratory facilities, or regional genetic differences.