Clinical implications of aminotransferase elevation in hospitalised infants aged 8-90 days with respiratory virus detection.

Background: Fever and respiratory symptoms are the major causes of hospitalisation in infants aged 90 days or less. Respiratory viruses (RVs) are detected by multiplex reverse transcriptase-polymerase chain reaction (mRT-PCR) in up to 70% of infants tested in this population. Aminotransferase elevation is not uncommon in RV infections, and repeat laboratory investigations are frequent due to concerns regarding the occurrence of hepatic disease.

Methods: This retrospective observational cohort study included 271 infants aged 8-90 days, with positive RV mRT-PCR results. Data were obtained on demographics, laboratory results and final diagnoses of hepatobiliary disease.

Results: Fever (73.1%) and/or respiratory symptoms (75.6%) were the major presentations among the hospitalised infants. Aspartate aminotransferase (AST) or alanine aminotransferase (ALT) levels were elevated in 62 (22.9%) of the 271 infants. Twenty-four of these 62 infants had their first follow-up, and 19 (79.2%) showed persistent elevation. All 10 (100%) infants who had their second follow-up showed persistently elevated aminotransferase levels. Eventually, none of the 10 infants were diagnosed with hepatic disease during the median follow-up of 10 days (range 3-232 days). Among the RVs of interest, parainfluenza virus type 1 was significantly associated with aminotransferase elevation (odds ratio: 2.95; 95% confidence interval [CI]: 1.11-7.83).

Conclusions: RV-related non-specific hepatitis is occasionally observed in infants aged 8-90 days, and ALT elevation is the most common abnormality. However, a final diagnosis of primary hepatobiliary disease appears to be rare. Therefore, regular follow-ups and targeted testing may be recommended in this specific population.