Rapid cytologic diagnosis of cytomegalovirus interstitial pneumonia on touch imprints from open-lung biopsy.

The diagnostic utility of Wright-Giemsa-stained touch imprints for identifying cytomegalovirus (CMV) in open-lung biopsies from marrow transplant recipients was studied. Of 41 consecutive biopsy specimens, 18 had culturally proven CMV, and 15 had typical intranuclear and intracytoplasmic inclusion bodies on permanent histologic sections. Wright-Giemsa-stained touch imprints from ten of the 15 biopsy specimens with CMV had characteristically enlarged cells containing 20-75 round to oval intracytoplasmic inclusions while only rarely containing intranuclear inclusions. The diagnosis of CMV from Wright-Giemsa-staining imprints (10/15) was superior to hematoxylin and eosin (H & E)-stained touch imprints (5/15) and H & E-stained frozen sections (2/15). Two cases of CMV had Papanicolaou-stained imprints that also demonstrated both intranuclear and intracytoplasmic inclusions. This simple technic of examining cytologic imprints from open-lung biopsy specimens will rapidly identify more than 50% of all confirmed cases of CMV, allowing earlier and possibly more successful antiviral therapy.