A study on the morbid histopathological changes in COVID-19 patients with or without comorbidities using minimally invasive tissue sampling

Abstract

Introduction: COVID-19 causes morbid pathological changes in different organs including lungs, kidney, liver,etc especially in those who succumb. Though clinical outcomes in those with comorbidities are known to be different from those without – not much is known about the differences at histopathological level.

Aims: It was to compare the morbid histopathological changes in COVID-19 patients between those who were immunocompromised(Gr 1), malignancy(Gr 2) or had cardiometabolic conditions (hypertension, diabetes or coronary artery disease)(Gr 3).

Methods: Post-mortem tissue sampling (MITS) was done from the lungs, kidney, heart, and liver using biopsy gun within two hours of death. Routine (H & E stain) and special stains (AFB, SM, PAS) were done besides immunohistochemistry.

Results: A total of 100 patients underwent MITS and data of 92 were included (immunocompromised: 27, maligancy:18, cardiometabolic conditions:71). Within lung histopathology, capillary congestion was more in those with malignancy while others like diffuse alveolar damage, microthrombi, pneumocyte hyperplasia etc was equally distributed. Within liver, architecture distortion was significantly different in immunocompromised while steatosis, portal inflammation, Kupffer cell hypertrophy, confluent necrosis were equally distributed. There was a trend towards higher acute tubular injury in those with cardiometabolic conditions as compared to the other groups. No significant histopathological differences in heart was discerned.

Conclusion: Certain histopathological features are markedly different in different groups (Gr 1,2 and3)of COVID-19 patients with fatal outcome.