Pulmonary cytology in lung transplant recipients: recent trends in laboratory utilization

The value of bronchoscopy for the diagnosis of rejection and opportunistic infection in lung transplant recipients is controversial. We review our experience with pulmonary cytology obtained from 10 lung transplant recipients during the first 15 mos of the transplantation program at Cedars-Sinai Medical Center and compare the efficacy of pulmonary cytology for the diagnosis of opportunistic infectious agents with that of histology and microbiology. Our study encompasses 1,465 post-transplant days during which 70 bronchoscopies were performed yielding 94 cytologic specimens (44 bronchial washes, 25 bronchial brushings, and 25 bronchoalveolar lavages) and 55 transbronchial biopsies. The major advantages of cytology in this setting are short turn around time and high specificity for nonbacterial agents. All of the patients experienced episodes of bacterial pneumonia as well as fungal and viral infections. None developed Pneumocystis carinii infection during the study period. Simultaneous and concurrent infections were diagnosed. The initial diagnosis of bacterial pneumonia and herpes simplex virus preceded the diagnosis of cytomegalovirus; the former infections tended to persist and/or recur. Cytology was more effective than histology in establishing the diagnosis of Candida sp. and herpes simplex virus, while histology was more effective in establishing the diagnosis of cytomegalovirus. Increased numbers of polymorphonuclear cells did not constitute a consistent finding in cytologic or histologic samples during episodes of bacterial infection; cultures were most sensitive for detection of bacterial infection. Histochemical and immunohistochemical stains as well as in situ hybridization studies confirmed diagnoses rendered on routine Papanicolaou and hematoxylin and eosin stained material but did not provide additional diagnoses.(ABSTRACT TRUNCATED AT 250 WORDS)