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

COVID-19 causes morbid pathological changes in different organs including lungs, kidneys, liver, and so on, 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 the histopathological level. To compare the morbid histopathological changes in COVID-19 patients between those who were immunocompromised (Gr 1), had a malignancy (Gr 2), or had cardiometabolic conditions (hypertension, diabetes, or coronary artery disease) (Gr 3), postmortem tissue sampling (minimally invasive tissue sampling [MITS]) was done from the lungs, kidney, heart, and liver using a biopsy gun within 2 hours of death. Routine (hematoxylin and eosin) and special staining (acid fast bacilli, silver methanamine, periodic acid schiff) was done besides immunohistochemistry. A total of 100 patients underwent MITS and data of 92 patients were included (immunocompromised: 27, malignancy: 18, cardiometabolic conditions: 71). In lung histopathology, capillary congestion was more in those with malignancy, while others like diffuse alveolar damage, microthrombi, pneumocyte hyperplasia, and so on, were equally distributed. In liver histopathology, architectural distortion was significantly different in immunocompromised; while steatosis, portal inflammation, Kupffer cell hypertrophy, and 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 difference in the heart was discerned. Certain histopathological features were markedly different in different groups (Gr 1, 2, and 3) of COVID-19 patients with fatal outcomes.

Clinico-pathological features in fatal COVID-19 infection: a preliminary experience of a tertiary care center in North India using postmortem minimally invasive tissue sampling

OBJECTIVES

To study the histopathology of patients dying of COVID-19 using post-mortem minimally invasive sampling techniques.

METHODS

This was a single-center observational study conducted at JPNATC, AIIMS. Thirty-seven patients who died of COVID-19 were enrolled. Post-mortem percutaneous biopsies were taken from lung, heart, liver, kidney and stained with hematoxylin and eosin. Immunohistochemistry was performed using CD61 and CD163. SARS-CoV-2 virus was detected using IHC with primary antibodies.

RESULTS

The mean age was 48.7 years and 59.5% were males. Lung histopathology showed diffuse alveolar damage in 78% patients. Associated bronchopneumonia was seen in 37.5% and scattered microthrombi in 21% patients. Immunopositivity for SARS-CoV-2 was observed in Type II pneumocytes. Acute tubular injury with epithelial vacuolization was seen in 46% of renal biopsies. Seventy-one percent of liver biopsies showed Kupffer cell hyperplasia and 27.5% showed submassive hepatic necrosis.

CONCLUSIONS

Predominant finding was diffuse alveolar damage with demonstration of SARS-CoV-2 protein in the acute phase. Microvascular thrombi were rarely identified in any organ. Substantial hepatocyte necrosis, Kupffer cell hypertrophy, microvesicular, and macrovesicular steatosis unrelated to microvascular thrombi suggested that liver might be a primary target of COVID-19.

A Canadian cancer trials group phase IB study of durvalumab (anti-PD-L1) plus tremelimumab (anti-CTLA-4) given concurrently or sequentially in patients with advanced, incurable solid malignancies

Background The IND.226 study was a phase Ib study to determine the recommended phase II dose of durvalumab + tremelimumab in combination with standard platinum-doublet chemotherapy. Sequential administration of multiple agents increases total chair time adding costs overall and inconvenience for patients. This cohort of the IND.226 study evaluated the safety and tolerability of durvalumab + tremelimumab given either sequentially (SEQ) or concurrently (CON). Methods Patients with advanced solid tumours were enrolled and randomised to either SEQ tremelimumab 75 mg IV over 1 h followed by durvalumab 1500 mg IV over 1 h q4wks on the same day, or CON administration over 1 h. The serum pharmacokinetic profile of SEQ versus CON of durvalumab and tremelimumab administration was also evaluated. Results 14 patients either received SEQ (n = 7pts) or CON (n = 7 pts). There were no infusion related reactions. Drug related adverse events (AEs) were mainly low grade and manageable, and comparable in frequency between SEQ/CON- fatigue (43%/57%), rash (43%/43%), pruritus (43%/29%) and nausea (14%/29%). One patient in each cohort discontinued treatment due to toxicity. The PK profiles of durvalumab and tremelimumab were similar between CON and SEQ, and to historical reference data. Conclusions Concurrent administration of durvalumab and tremelimumab over 1 h is safe with a comparable PK profile to sequential administration.