Clinical features and outcome of hospitalized patients with HSV-1 DNA in the lower respiratory tract

The aim of this study was to define the clinical impact of Herpes simplex virus-1 (HSV-1) DNA detection in the low respiratory tract of hospitalized patients. Forty-nine patients admitted to the University Hospital Tor Vergata, Rome, Italy, from May 2013 to June 2014, were analysed. Inclusion criteria were the presence or absence of HSV-1 DNA in clinical routine bronchoalveolar lavage (BAL) fluid specimens. Nineteen individuals were positive (cases) and 30 negative (controls) for the presence of HSV-1 DNA. The two groups were matched for age, gender and month of BAL collection. Cases and controls differed significantly according to length of stay in hospital (p=0.027), ICU transfer (p=0.02), disease severity (p=0.003), death (p=0.009), haematological and blood chemistry tests. Among cases, survivors and deceased patients differed significantly regarding ICU transfer (p=0.0001), mechanical ventilation (p=0.0048), disease severity (p=0.028) and risk of death (p=0.013). A trend towards higher HSV-1 loads was observed in the cases who died. These results suggest that detection of HSV-1 DNA in BAL fluid specimens is a marker of disease severity and poor outcome. Further prospective studies are necessary to deepen the clinical significance of HSV-1 DNA detection in the lower respiratory tract of hospitalized patients.