Histopathological Profile of Lung Lesions- An Autopsy Study at a Tertiary Care Centre, Kerala, India

Abstract

Introduction: Autopsy plays a crucial role in understanding and identifying pulmonary pathology, encompassing non neoplastic lesions, neoplastic conditions and the secondary implications of the lungs in terminal events of cardiovascular diseases. Pathological analysis confirms diagnosis and identifies the prevalence of lesions, contributing significantly to medical understanding and patient care. Aim: To estimate the prevalence of lung pathology in autopsy specimens through Histopathological Examination (HPE). Materials and Methods: A cross-sectional one-year study was conducted to determine the histopathological alterations in 132 lung autopsy specimens from Medicolegal autopsies received in the Department of Pathology at a tertiary care centre in Government Medical College, Cochin, Kerala, India from January 2021 to December 2021. Autopsy specimens of the lung were fixed in 10% formalin. Following gross examination, tissue sections were processed with paraffin and subjected to staining, with microscopy findings recorded. The data was numerically coded and entered into a Microsoft Excel spreadsheet. Statistical Package for Social Sciences (SPSS) version 21.0 was used for descriptive statistics and graphical representations of findings. Results: The mean age of the study population, comprising 132 autopsy cases, was 49.41±52.12 years and the male-to- female ratio was 3.71:1. Most cases 97/132 (73.50%) involved sudden deaths where the cause remained unknown. Significant microscopic findings found in 117 (88.63%) cases were as follows: Pulmonary oedema and congestion: 61 (46.21%), Pneumonia: 17 (12.87%), Diffuse Alveolar Damage (DAD): 12 (9.09%), Chronic venous congestion: 8 (6.06%), Tuberculosis: 7 (5.30%), Emphysema: 7 (5.30%), Pulmonary fibrosis: 1 (0.75%), Fat embolism: 1 (0.75%) and Pulmonary arterial hypertension: 1 (0.75%). Neoplastic lesions were identified in 7 (5.30%) cases, with primary lung cancers accounting for 3 (2.27%) cases. There were 10 cases of Real-time Reverse Transcriptase-Polymerase Chain Reaction (RT-PCR), positive Coronavirus Disease 2019 (COVID-19) autopsies, of which 6 (60%) exhibited DAD, while 4 (40%) showed changes of bronchopneumonia. Conclusion: Non neoplastic lesions such as pulmonary oedema, DAD and infections contributed to mortality in most cases. DAD was the most common lung finding in more than half of COVID- 19 deaths. The prevalence of pulmonary neoplastic lesions in autopsies underscores their epidemiological significance in a particular geographical area.