Clinical features and outcome of maintenance hemodialysis patients with COVID-19 from a tertiary nephrology care center in Romania.

BACKGROUND: There is limited information about the clinical characteristics, treatment and outcome of maintenance hemodialysis patients with COVID-19. Moreover, regional differences are also conceivable since the extend and severity of outbreaks varied among countries. METHODS: In this retrospective, observational, single-center study, we analyzed the clinical course and outcomes of 37 maintenance hemodialysis patients (median age 64 years, 51% men) hospitalized with COVID-19 from 24 March to 22 May 2020 as confirmed by real-time PCR. RESULTS: The most common symptoms at admission were fatigue (51%), fever (43%), dyspnea (38%) and cough (35%). There were 59% mild/moderate patients and 41% severe/critical patients. Patients in the severe/critical group had a significantly higher atherosclerotic burden since diabetic kidney disease and vascular nephropathies were the most common primary kidney diseases and eighty percent of them had coronary heart disease. Also, Charlson comorbidity score was higher in this group. At admission chest X-ray, 46% had ground-glass abnormalities. Overall, 60% patients received hydroxychloroquine, 22% lopinavir-ritonavir, 11% tocilizumab, 24% systemic glucocorticoids, and 54% received prophylactic anticoagulation. Seven (19%) patients died during hospitalization and 30 were discharged. The main causes of death were cardiovascular (5 patients) and respiratory distress syndrome (2 patients). In Cox regression analysis, lower oxygen saturation, anemia and hypoalbuminemia at admission were associated with increased mortality. CONCLUSIONS: In conclusion, we observed a high mortality rate among maintenance hemodialysis patients hospitalized for COVID-19. Anemia, lower serum albumin and lower basal oxygen saturation at admission were factors associated with poor prognosis.

Abdominal aortic calcification and renal resistive index in patients with chronic kidney disease: is there a connection?

BACKGROUND: We aimed to evaluate the relationship between abdominal aortic calcification (AAC) and renal resistive index (RRI), parameters associated with cardiovascular outcome, in non-dialysis chronic kidney disease (CKD) patients. METHODS: Seventy-seven stable patients mainly in CKD stages 3B and 4 (44 and 28%), median age 69 years, with a positive history of systemic atherosclerosis were prospectively enrolled. RRI, carotid intima-media thickness (IMT), Kauppila score for AAC (AACs), cardio-ankle vascular index (CAVI) and ankle-brachial index (ABI) were assessed. Traditional and non-traditional atherosclerosis risk factors were also evaluated. RESULTS: Vascular (50%), diabetic (26%) and primary glomerular nephropathies (8 %) were the main causes of CKD. AAC was highly prevalent (77%). In the whole cohort, RRI was directly related to AACs (rs = 0.35, p < 0.001). AACs correctly identified patients with RRI >0.7 in 69% (56-81%) of cases, a cut-off of 5 resulting the best combination of sensitivity (65%) and specificity (68%). Compared to those with AACs <5, patients with AACs >5 were older, had higher serum cholesterol, C-reactive protein and IMT, lower ABI, but similar CAVI, estimated glomerular filtration rate, serum calcium and phosphate. In the whole cohort, AACs was negatively correlated with ABI (rs = -0.51, p < 0.001) and positively with IMT (rs = 0.27, p = 0.01), supporting a role for Kauppila score in integrating information on both intra- and extrarenal atherosclerosis. CONCLUSIONS: As Kauppila score correlates with RRI in non-dialysis CKD patients, it could be a fast, convenient and relatively inexpensive tool for estimating RRI, and consequently the intrarenal vascular status, but further research is warranted.

Tuberculin skin test, interferon-gamma assay, and T cells subpopulations in hemodialysis patients.

OBJECTIVE: To examine and compare the responses of hemodialysis (HD) patients to Mycobacterium tuberculosis antigens by using the tuberculin skin test (TST) and an interferon gamma assay (IFN-TB), and to investigate the relationship between T cells subpopulations and tests results. Observational, prospective, diagnostic study conducted in a HD center in a country with high prevalence of tuberculosis. PATIENTS: 195 patients on maintenance HD who consented to participate in this study; 187 (6 were excluded for refusing TST and 2 for indeterminate responses to IFN-TB) were HIV negative, vaccinated with the Bacille Calmette-Guerin vaccine, and without any signs of active tuberculosis, were selected. METHODS: Similar to the Mantoux method, 10 IU tuberculin was used for the TST. An IFN-gamma assay specific for Mycobacterium tuberculosis antigens and phytohemagglutinin was carried out. Flow cytometry analysis of peripheral lymphocytes was also performed. RESULTS: TST and IFN-TB results were found to be positive (44% and 53%, respectively) or negative (32% and 47%, respectively) in similar proportions. Results were in agreement in 71% of positive and 58% of negative tests. IFN-gamma levels were found to be higher in patients with a positive TST. All cell counts and CD4/CD8 were found to be higher in TST-positive patients, whereas only total lymphocytes count and CD4/CD8 were reported to be high in IFN-TB-positive patients. A model of multivariable linear regression including cell counts explained 16% of the mitogen-induced IFN-gamma production (F = 5,11; P = .0003). The majority of subjects with positive tests were younger, in most cases male, belonged to the Roma ethnic group, had a shorter HD vintage, and a better nutritional status. CONCLUSIONS: TST and IFN-gamma production stimulated by Mycobacterium tuberculosis antigens rely on patient's immune status, which could be influenced by either individual (age, gender), dialysis-related (HD vintage), or nutritional factors. In addition, the diagnostic utility for tuberculosis is similar and moderate in HD patients.