Acute Hepatitis of Unknown Origin in Children: Two Cases in a Portuguese Hospital


  • Ricardo Craveiro Costa Centro da Criança e do Adolescente. Hospital CUF Descobertas. Lisboa.
  • Catarina Schrempp Esteves Centro da Criança e do Adolescente. Hospital CUF Descobertas. Lisboa.
  • Pedro Flores Centro da Criança e do Adolescente. Hospital CUF Descobertas. Lisboa.
  • Luís Varandas Centro da Criança e do Adolescente. Hospital CUF Descobertas. Lisboa; Institute of Hygiene and Tropical Medicine. Universidade NOVA de Lisboa. Lisboa; Faculdade de Ciências Médicas | NOVA Medical School. Universidade Nova de Lisboa. Lisboa.



Acute Disease, Child, Disease Outbreaks, Hepatitis, Portugal


Several cases of paediatric acute hepatitis of an unknown aetiology have been described in these last few months and in several countries worldwide. We present two patients, a 7-month-old girl and an 8-year-old boy, with gastrointestinal symptoms and lethargy, associated with elevation of transaminase levels. Serologies for hepatitis A-E virus and PCR test to SARS-CoV-2 were all negative. In the first case, an adenovirus serotype C could be isolated in a respiratory sample as well as cytomegalovirus (CMV) in the blood (100 copies/mL). In both children, there was a progressive decrease in the hepatic markers and symptomatic resolution, compatible with a good prognosis, also seen globally in most cases. To date, infection remains the most plausible cause to consider, especially when it is presumed to be linked to adenovirus. Other potential agents and causes are still being evaluated, thus emphasizing the importance of continuous epidemiological surveillance, notification, and detailed study of all hepatitis cases.


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How to Cite

Craveiro Costa R, Schrempp Esteves C, Flores P, Varandas L. Acute Hepatitis of Unknown Origin in Children: Two Cases in a Portuguese Hospital. Acta Med Port [Internet]. 2023 Jan. 25 [cited 2024 Apr. 25];36(7-8):506-10. Available from:



Case Report