Quantification of viral DNA and liver enzymes in plasma improves early diagnosis and management of herpes simplex virus hepatitis

Summary.  Herpes simplex virus (HSV) hepatitis is a rare and potential life‐threatening disease. The diagnosis of HSV hepatitis is hampered by its indifferent clinical presentation, which necessitates confirmatory laboratory data to identify HSV in the affected liver. However, liver biopsies are often contraindicated in the context of coagulopathy, are prone to sampling errors and have low sensitivity in mild HSV hepatitis cases. There is an unmet need for less invasive diagnostic tools. The diagnostic and therapeutic value of HSV DNA load and liver enzyme level kinetics was determined in five patients with HSV hepatitis and twenty disease controls with HSV‐DNAemia without hepatitis. At time of hospitalization, patients with HSV hepatitis had a higher median (± interquartile range) HSV DNA load (6.0 × 106 ±1.2 × 109) compared to disease controls (171 ± 2845). Viral DNA load correlated with liver transaminase levels and disease severity. Antiviral treatment led to rapid decline of HSV DNA load and improvement of liver function of patients with HSV hepatitis. The data advocate the prompt and consecutive quantification of the HSV DNA load and liver enzyme levels in plasma of patients suspected of HSV hepatitis as well as those under antiviral treatment.