ABSTRACT
Background: The SARS-CoV-2 virus led to the COVID-19 pandemic, which affected the health of the world population immensely, as well as demonstrated the multi-organ involvement of patients experiencing severe manifestations of COVID-19. Although the symptoms were mainly of the respiratory system, data showed that SARS-CoV-2 triggered extensive histopathology alterations in different body organs. The insights into these microscopic changes have played a pivotal role in the discovery of the pathogenesis of the virus as well as the forecast of the possible long-term consequences.
Objective: The purpose of the study was to conduct the investigation and description of the histopathological changes of various organs of the patients infected with COVID-19 and gain new insights into the pathogenesis of the virus and its long-term impact on the body systems.
Methods: This descriptive study was done on a hospital basis and the cases were done in PIMS Islamabad in the time period June 2024 till May 2025. Ninety autopsy cases of patients who died because of COVID-19 were chosen. The postmortem tissue samples on lungs, heart, liver, kidneys and brain were taken and processed by the standard histopathologic techniques. Hematoxylin and eosin (H&E) staining was done and the results observed at microscopic scale by skilled pathologists. Analysis of data was done to evaluate the kind and frequency of the changes affecting the tissues in the sampled organs.
Results: Histopathological assessment indicated that Lung tissues showed diffuse alveolar injury in majority of 86% of the cases, showing formation of hyaline membrane and lymphocytic inflammation of the interstitial tissue. Focal myocarditis and microthrombi were evident in 48 percent of samples in the myocardial tissues. Centrilobular necrosis and macrovesicular steatosis were found in 41 percent cases of hepatic samples. In 52 percent of patients, renal tissue showed an acute tubular injury and in 29 percent of patients, there were glomerular microthrombi. In 33%, a microglial activation and some isolated perivascular bleeding was also observed in brain tissue. These results proved the multi-organ affection and showed that pathological changes did not stop even in those who died fairly early in the disease episode.
Conclusion: The research concluded that infected SARS-CoV-2 caused considerable tissues alterations not only in lung tissue but in various other organs as well. These observations gave the important understanding of the processes of viral transmission and specific organ destruction. Identification of these changes may be helpful in clinical management as well as long-term follow-up of patients previously hospitalized with COVID-19 and in predicting patients most likely to develop post-viral sequelae.
Keywords: COVID-19, histopathology, organ damage, viral pathogenesis, SARS-CoV-2, postmortem findings, long-term effects, PIMS Islamabad.