Cytological features suggesting herpes simplex virus (HSV) infection in
samples obtained at bronchoscopy have been described only very rarely in routinely
processed samples. We report four cases where evidence of HSV infection was
identified morphologically in samples processed using thin-layer techniques, with
polymerase chain reaction confirmation of the presence of virus in three cases.
We suggest that the increased morphological clarity provided by this technique for
processing these cytology samples may result in the morphological features of viral
infection being seen more frequently. Pathologists reporting such samples need to be
aware of this possibility in order to avoid potential misinterpretations. In addition,
however, respiratory and intensive care physicians unused to receiving cytology
reports indicating ‘HSV infection’ need to be aware that the significance is uncertain
and in most cases it is likely to indicate the reactivation of a latent infection.
