Cytological diagnosis of bronchopneumonia at post mortem

We assessed the value of cytology in the rapid diagnosis of bronchopneumonia at post mortem. Cytology scrapes were taken from 249 lung lobes during 50 autopsies. Slides were stained with a modified Giemsa technique and a neutrophil polymorph score recorded on a scale of 0-3. Histology blocks from the same area were then scored for the degree of bronchopneumonia present. Bronchopneumonia was found histologically in 22 patients, but macroscopic examination had identified only eight of these. A cytological neutrophil polymorph score of 2 or more to indicate bronchopneumonia yielded a sensitivity of 52% and a specificity of 98% in terms of lobes. This gave a positive predictive value of 92% and a negative predictive value of 86% for the presence of bronchopneumonia. All eight patients with a cytology score of 3 had histological evidence of bronchopneumonia. Conversely, all patients with a definitive diagnosis of bronchopneumonia exhibited cytology scores of at least 1. Post mortem cytology scrapes reliably predict bronchopneumonia and are superior to gross examination. This is a rapid, reliable and cheap method that can be readily performed in all necropsy practices.