Microsatellite analysis of HSV-1 isolates: from oropharynx reactivation toward lung infection in patients undergoing
C Deback1, C E Luyt, S Lespinats
1UPMC Univ. Paris 06, ER1 DETIV, F-75013 Paris, France. claire.deback@psl.aphp.fr
Background:
According to recent reports, herpes simplex virus type 1 (HSV-1) induces bronchopneumonitis (BPn) in immunocompetent patients undergoing prolonged mechanical ventilation (MV), whose respiratory functions deteriorate with a poor outcome. HSV-1 BPn is associated with HSV symptomatic or symptomless reactivation in the oropharynx.
Objectives:
We sought to systematically and genetically characterize HSV-1 strains isolated from immunocompetent patients receiving prolonged MV and to characterize the genetic relationship of strains sequentially isolated from oropharyngeal samples (OPS) and broncho-alveolar liquids (BAL) to determine the natural course of HSV BPn.
Study Design:
In this molecular epidemiological study, microsatellite technology was used to determine genetic relationships between 211 HSV-1 strains isolated from OPS and/or BAL from 106 patients receiving MV.
Results:
Microsatellite haplotypes of HSV-1 strains sequentially isolated from the same individual were identical, and HSV-1 isolates from the lung were genetically indistinguishable from strains isolated from the oral cavity. Each patient was characterized by their own HSV-1 microsatellite haplotype, and no nosocomial transmission of strains between patients was observed.
Conclusion:
Our results demonstrate that, in patients who receive MV, the HSV-1 pulmonary infection results from the reactivation of genetically related HSV-1 in the oropharynx, which progressively infects the lower respiratory tract.
