Inflammatory Response and Hepatic Injury Markers in Children and Adult Patients Infected with Influenza Virus: A Hospital-Based Cross-Sectional Study

Influenza mainly involves the pulmonary system, but may cause damage to other organs like liver, kidneys, and bone marrow. It is essential to identify changes in the laboratory markers indicating inflammation and hepatic injury; and changes in white blood cell count in patients with flu. This study aimed to evaluate these laboratory markers and compare them in children and adults.

This retrospective study was performed in three university hospitals in Qazvin, Iran. Clinically available laboratory biomarkers including some inflammatory markers (e.g. CRP and ESR) , marker of hepatic injury (AST, ALT, ALP, billirubin, prothrombin time), and white blood cell count of 435 definite inflenza patients with positive influenza RT-PCR in 2018 and 2019 were collected from their medical records. The results were classified based on age (over 14 years of age in adults) and the normal range reported by the performing laboratory. Using SPSS software 25, data were analyzed by chi-square and pearson correlation coefficient test. P<0.05 was considered significant.

Leukocytosis was observed in 22.5% of adults and 1.0% of children, and the difference between the two groups was significant (p<0.001). ESR was increased in 91.6% of children and 86.9% of adults;CRP was elevated in 34.7% of adults while 80.5% of children showed elevation (p<0.001). The duration of hospital stay was significantly correlated with ESR (p<0.001, r= 0.177), and CRP (p= 0.002, r= 0.163).The increase in ALT was detected in 32.1% of adults versus 10.0% of children and AST in 38.6% of adults versus 10.0% of children. This increase in both liver enzymes was greater in adults compared with children (p<0.044 and p<0.013, respectively). 42.4% of adults, showed increased prothrombin time.

Leukocytosis, CRP elevation and increase in liver enzymes during influenza seems to be more pronounced in adults than in children. The results also showed a significant relationship between a hospital stay and the level of ESR and CRP.