Evaluation of bone marrow findings of COVID-19 by minimally invasive autopsies: A single tertiary care centre experience from India

ABSTRACT

Aims & Objectives: The 2019 novel coronavirus (2019-nCoV) or the severe acute respiratory syndrome corona virus 2 (SARS-CoV- 2), originated in Wuhan City of Hubei Province of China. In India, first confirmed case of coronavirus disease (COVID-19) was reported on January 30, 2020 and since then the virus has spread across the country. More than 7.9 million cases of COVID-19 and more than 1.19 lakh deaths have been reported in India. The pathobiology of the disease is poorly known, and significant efforts have been made to understand the disease process worldwide. Clinical autopsies are known to have a vital role in developing an understanding of the disease process. The aim of the present study was to evaluate bone marrow findings of COVID-19 by minimally invasive autopsies. Patients/Materials & Methods: This prospective study was conducted at All India Institute of Medical Sciences, Jodhpur. After obtaining approval from Institute's ethics committee and consent from next of kins, minimally invasive autopsies were conducted within an hour after the death. Procedures were done with all biosafety measures. The tissue specimens were kept in neutral buffered formalin for 48 h and then processed with standard biosafety measures. Electronic medical records were reviewed retrospectively and patients' clinical details and results of laboratory investigations were noted. Results: In this prospective study, bone marrow biopsy procedures were done in 37 COVID-19 minimally invasive autopsies. Mean age of these cases was 61.8 years (Range, 28-85 years) and male female ratio was 2.36. Comorbidities were observed in 25(67.5%) of all cases. Histopathological analysis revealed hypercellular, normocellular and hypocellular marrow in 5, 25 and 5 cases respectively (two biopsies were inadequate). There was marked interstitial prominence of histiocytes in 24(68.5%) cases. Out of these, evidence of haemophagocytosis (Figure 1) was observed in 14(40%) cases, marked increase of haemosiderin laden macrophages in 20(57.1%) cases. There was prominence of plasma cells in 28 (80%) cases. Discussion & Conclusion: Incorporation of minimally invasive autopsies provides an effective method to study the pathological findings in COVID-19 deaths in resource constrained settings. Histopathological findings in bone marrow suggest indirect insult to bone marrow, presumably related to circulatory and/or hyperinflammatory response to viral infections.