Alteration of bronchiolar club cells and pneumocytes as markers of fatal pulmonary toxicity from systemic agents: Considerations on a group of autopsy samples

Introduction: Club cells and pneumocytes may undergo qualitative and quantitative modifications when lungs are damaged and the modifications of these cells when the body is involved in systemic toxicity, thus when lung is not the target organ, may be an interesting challenge. Therefore, crucial information may be provided by the investigation of the feasibility of possible markers of lung damage in case of intoxication by different substances. Methods: For this reason, the study aimed at assessing the histological changes of club cells and type I-II pneumocytes in 85 cases of acute poisoning by exogenous substances, whilst controls were 50 cases of death related to non-toxic causes. A total of 405 histological thin sections were analyzed after staining with hematoxylin-eosin, Masson’s trichrome and Periodic acid–Schiff (PAS). Results: The results showed a numerical variation of club cells and type I and type II pneumocytes depending on the toxic agent examined. Conclusion: It is therefore possible to ascribe to this kind of bronchiolar cells a detoxifying effect, capable of detecting lung injuries in an early stage and which may represent a marker (although not specific for the substance) even when lungs are not directly involved among a systemic toxic mechanism.