T-cell responses in COVID-19 survivors 6-8 months after infection: A longitudinal cohort study in Pune.

BACKGROUND: The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) immune response is crucial for disease management, although diminishing immunity raises the possibility of reinfection. METHODS: We examined the immunological response to SARS-CoV-2 in a cohort of convalescent COVID-19 patients in matched samples collected at 1 and 6-8 months after infection. The peripheral blood mononuclear cells were isolated from enrolled study participants and flow cytometry analysis was done to assess the lymphocyte subsets of naive, effector, central memory, and effector memory CD4+ or CD8+ T cells in COVID-19 patients at 1 and 6-8 months after infection. Immunophenotypic characterization of immune cell subsets was performed on individuals who were followed longitudinally for 1 month (n = 44) and 6-8 months (n = 25) after recovery from COVID infection. RESULTS: We observed that CD4 +T cells in hospitalized SARS-CoV-2 patients tended to decrease, whereas CD8+ T cells steadily recovered after 1 month, while there was a sustained increase in the population of effector T cells and effector memory T cells. Furthermore, COVID-19 patients showed persistently low B cells and a small increase in the NK cell population. CONCLUSION: Our findings show that T cell responses were maintained at 6-8 months after infection. This opens new pathways for further research into the long-term effects in COVID-19 immunopathogenesis.

Lymphopenia with Altered T Cell Subsets in Hospitalized COVID-19 Patients in Pune, India.

The cellular immune cell subsets affecting COVID-19 disease severity are being studied by researchers from many countries. The current study was carried out to investigate the alteration of peripheral blood mononuclear cells (PBMCs) and their subsets in hospitalized COVID-19 patients in a tertiary care center in Pune, India. The PBMCs were isolated from enrolled study participants, and flow cytometry analysis was done to assess peripheral white blood cell alterations. The lymphocyte subsets of naive, effector, central memory, and effector memory CD4+ or CD8+ T cells were then evaluated in COVID-19 patients with different disease categories and compared to healthy controls. The immunophenotypic characterization of the immune cell subset was done for 139 COVID-19 patients and 21 healthy controls. These data were evaluated based on the disease severity. A total of 139 COVID-19 patients were classified as mild (n = 30), moderate (n = 57), or severe (n = 52) cases. The decreased percentages of total lymphocytes, CD3+ T cells, CD4+ T cells, naive T cells, central memory T cells, and Natural Killer (NK) cytotoxic cells were found, and there was increase in effector T (TEf) cells and effector memory T cells in patients with severe COVID-19 compared to healthy controls. The severity of SARS-CoV-2 infection has an effect on lymphocyte subsets, resulting in reduced T memory cells and NK cells but increased TEf cells in severe cases. Clinical Trial Registration: CTRI ID-CTRI/2021/03/032028.

Clinical Profile and Treatment Outcome of Drug Resistant Tuberculosis Patients of Western Maharashtra, India.

BACKGROUND: Drug-resistant tuberculosis (DR-TB) imposes formidable burden on national health systems. OBJECTIVES: This study aims to evaluate clinical profile and treatment outcome of drug resistant tuberculosis patients at tertiary care centre using a standardised treatment regimen (STR). METHODS: Retrospective analysis of 146 patients with DR-TB from Solapur district who were treated with STR from period of September 2012 to December 2014 was done. Statistical analysis of treatment outcome data was done to know predictors of treatment success of DR-TB. RESULTS: Out of total 146 bacteriologically proven cases of DR-TB, 95 were males and 51 females. 41% of patients were residents of Solapur city and the rest from different parts of Solapur district. Out of the 146 patients, 130 (89%) patients achieved sputum culture conversion within three months. Treatment outcome of these patients was as followstreatment success in 84 (58%), 20(14%) died, 28(19%) defaulted and failure in 14(9%) patients. Three predictors were identified for successful treatment outcome of DR-TB that include urban residence, patients with chest x-ray findings of moderately advanced disease and patients whose DR-TB status diagnosed by genexpert technology. CONCLUSION: In resource-poor settings, well-designed STR under national programme provides satisfactory results.

To Study Efficacy of Medical Thoracoscopy in Undiagnosed Pleural Effusions.

BACKGROUND: Medical thoracoscopy has received interest in recent past for diagnostic as well as therapeutic uses. In this study we describe our experience with diagnostic medical thoracoscopy in pleural effusions of undiagnosed etiology. OBJECTIVE: 1.To detect diagnostic yield of medical thoracoscopy in pleural effusions of unknown etiology. 2.To find complication rate in these patients. METHODOLOGY: In a retrospective analysis of thoracoscopic procedures performed between March 2011 and December 2014, diagnostic yield and complications of thoracoscopic pleural biopsy for achieving a diagnosis in undiagnosed pleural effusions were evaluated. STATICAL ANALYSIS: Statistical analysis of all 60 patients underwent thoracoscopy was done and findings expressed in terms of percentages. RESULTS: A total of 60 patients (40 males and 20 females; mean age 45 years) underwent diagnostic pleuroscopy. Tuberculosis was diagnosed in 28 patients, Malignancy was found in 26 patients, three patients had pyogenic infections(empyema) and it was non diagnostic in three patients. There were no major complications, minor complications were observed in 10 patients(17%). INTERPRETATIONS: The diagnostic yield of medical thoracoscopy in our study was 95%. Minor complications were noted in ten patients (17%). CONCLUSIONS: Medical thoracoscopy is a valuable tool in the diagnosis of undiagnosed exudative pleural effusion. It is a simple and safe method with high diagnostic yield and with low complication rates.