SUMMARY BACKGROUND: The COVID-19 pandemic has affected the entire world, posing a serious threat to human health. T cells play a critical role in the cellular immune response against viral infections. We aimed to reveal the relationship between T cell subsets and disease severity. METHODS: 40 COVID-19 patients were randomly recruited in this cross-sectional study. All cases were confirmed by quantitative RT-PCR. Patients were divided into two equivalent groups, one severe and one nonsevere. Clinical, laboratory and flow cytometric data were obtained from both clinical groups and compared. RESULTS: Lymphocyte subsets, CD4+ and CD8+ T cells, memory CD4+ T cells, memory CD8+ T cells, naive CD4+ T cells, effector memory CD4+ T cells, central memory CD4+ T cells, and CD3+CD4+ CD25+ T cells were significantly lower in severe patients. The naive T cell/CD4 + EM T cell ratio, which is an indicator of the differentiation from naive T cells to memory cells, was relatively reduced in severe disease. Peripheral CD4+CD8+ double-positive T cells were notably lower in severe presentations of the disease (median DP T cells 11.12 µL vs 1.95 µL; p< 0.001). CONCLUSIONS: As disease severity increases in COVID-19 infection, the number of T cell subsets decreases significantly. Suppression of differentiation from naive T cells to effector memory T cells is the result of severe impairment in adaptive immune functions. Peripheral CD4+CD8+ double-positive T cells were significantly reduced in severe disease presentations and may be a useful marker to predict disease severity.

Background/aim: In this study, we aim to investigate the efficacy of convalescent plasma (CP) according to blood groups (BGs) in the treatment of critically ill patients diagnosed with COVID-19. Materials and methods: Twenty-eight critically ill and laboratory-confirmed COVID-19 patients who were admitted to the intensive care unit (ICU) of Sakarya University, Medical Faculty were included in the study. Patients were divided into 2 groups: patients who received anti-A antibody (Ab) containing CP (BG O and B) and those who did not receive CP containing anti-A Ab (BG A and AB). Results: Among the 28 patients, 13 patients received anti-A Ab containing CP (BG; B: 6, O: 7) and 15 patients did not receive anti-A Ab CP (BG; A: 13, AB: 2). Duration in ICU, the rates of mechanical ventilation (MV) support and vasopressor support, the case fatality rate, and the discharge rate were lower in patients who received CP containing anti-A Ab than not containing anti-A Ab CP. However, only the difference in the rate of MV support achieved statistically significance (P = 0.04) Conclusion: In our study, it was observed that the efficiency of CP without anti-A antibody was lower than that of plasma containing anti-A antibody, although it was not statistically significant. This result is thought to be due to the anti-A antibody's ability to block the ACE2 receptor. We believe that this hypothesis should be investigated in controlled studies with higher patient numbers.

Objectives: In this study, we aimed to investigate capillary vessel diameters and structural changes of capillaries by using nailfold video capillaroscopy (NVC) in patients with polycythemia vera (PV). Patients and Methods: This cross-sectional study included a total of 24 patients (19 males, 5 females; mean age: 59.8±12.9 years; range, 50.2 to 68 years) who were diagnosed with PV and 15 healthy controls (11 males, 4 females; mean age: 40.7±5.1 years; range, 36 to 44 years) between June 2016 and February 2017. Nailfold video capillaroscopy was performed by an experienced rheumatologist who was blinded to clinical data. The apical, arterial, and venous limb diameters of capillaries were measured and microvascular changes of capillaries were scored. Results: When capillaries were evaluated in terms of morphological structures, giant capillary was detected in 67% of the patients with PV and 0% in the control group (p

OBJECTIVE: The aim of this study was to compare the incidence of factors associated with an increased risk of thrombosis in patients with essential thrombocythemia. METHODS: A total of 200 patients followed-up in our unit with a diagnosis of essential thrombocythemia in 13 years were analyzed retrospectively. RESULTS: Of the study participants, 60.5% were females and 39.5% were males, with an overall mean (+/- SD) age of 54.93 (+/- 14.21) years. In 119 patients, Janus Kinase 2 was positive with 56.3% of cases. When two patient categories were defined as those with or without history of thrombosis, no significant differences were found in terms of Janus Kinase 2 positivity, mean age, as well as white blood cells and platelet counts (p>0.05). Also, no significant differences in thrombotic event incidence were found between patient categories defined on the basis of cut-off values for white blood cells (cut-off values of 15x10(3)/mm(3) and 8.7x10(3)/mm(3)) and platelets (cut-off values of 1500x10(3)/mm(3)) (p>0.05). CONCLUSION: Although our results are generally in line with the published data, some divergence from previous results has been observed with respect to risk factors for thrombotic events. Absence of a correlation between leukocytosis and thrombosis may be related with the significant decline in white blood cells after treatment. Also, a significant reduction in platelet counts occurring in association with treatment is linked with a lowered incidence of thrombosis. Janus Kinase 2-positive patients had a similar thrombosis frequency with that reported in the literature.

There are different drug combinations and conditioning regimens in lymphoma transplants. However, no randomized data is available to demonstrate the superiority of any regimen and the optimal choice is unknown. In this analysis, we compared the efficacy, toxicity and the survival outcomes of the BEAM and the high dose ICE (hdICE) conditioning regimens in relapsed NHL and relapsed/refractory Hodgkin Lymphoma patients undergoing auto-SCT. 83 patients with relapsed/refractory HL or relapsed NHL who were treated with Auto-SCT between 2006 and 2016, were analyzed retrospectively. 52 patients (62.7%) received BEAM, while 31 patients (37.3%) received hdICE. Between two groups there is no significant difference in age, gender, diagnosis, disease stage, chemosensitivity, ECOG performance status, time from diagnosis to transplant, salvage regimens and previous lines of chemotherapy. After a median of 59-month follow-up, PFS and OS rates of both groups were similar (5-year PFS was 51.6% in BEAM group, 48.8% in hdICE group, p = 0.71; 5-year OS was 58% in BEAM group, 54.8% in hdICE group, p = 0.93). The median neutrophil (11 vs. 10 days, p = 0.06) and platelet engraftment (13 vs. 11 days, p = 0.01) was faster and demand of transfusions were lesser in hdICE group (p = 0.03). However, severe renal toxicity was significantly higher in hdICE group in our study (p = 0.01). hdICE conditioning regimen may be used as an alternative to BEAM, with similar survival outcomes and toxicity profile, especially transplant centers that experience some difficulties in the availability of the carmustine.