COVID-19 Infection in Chronic Kidney Disease Patients in Bulgaria: Risk Factors for Death and Acute Kidney Injury

Post-Acute Sequelae of SARS-CoV-2 Infection (PASC) for Patients-3-Year Follow-Up of Patients with Chronic Kidney Disease

Post-acute sequelae of SARS-CoV-2 (PASC) is a significant health concern, particularly for patients with chronic kidney disease (CKD). This study investigates the long-term outcomes of individuals with CKD who were infected with COVID-19, focusing on their health status over a three-year period post-infection. Data were collected from both CKD and non-CKD patients who survived SARS-CoV-2 infection and were followed for three years as part of a research study on the impact, prognosis, and consequences of COVID-19 infection in CKD patients. In this prospective cohort study, we analyzed clinical records, laboratory findings, and patient-reported outcomes assessed at intervals during follow-up. The results indicated no permanent changes in renal function in any of the groups analyzed, although patients without CKD exhibited faster recovery over time. Furthermore, we examined the effect of RAAS-blocker therapy over time, finding no influence on PASC symptoms or renal function recovery. Regarding PASC symptoms, most patients recovered within a short period, but some required prolonged follow-up and specialized post-recovery management. Following up with patients in the post-COVID-19 period is crucial, as there is still insufficient information and evidence regarding the long-term effects, particularly in relation to CKD.

IL-6 and SAA-Strong Predictors for the Outcome in COVID-19 CKD Patients

In this prospective study, we assessed biomarkers of inflammation (IL-6 and SAA) from the serum of 120 COVID-19 patients, of whom 70 had chronic kidney disease. All the samples were taken at emergency-department (ED) admission. Our goal was to relate the biomarkers to the results of death and acute kidney injury. All the patients underwent chest computer tomography to estimate the severity score (0-5), which was performed at hospital admission. Finally, biomarkers were also evaluated in a healthy control group and in non-COVID-19-CKD patients. IL-6 and SAA were statistically different between the subgroups, i.e., they were significantly increased in patients with COVID-19. Both of the biomarkers (IL-6 and SAA) were independently associated with mortality, AKI and a higher grade of pathological changes in the lung's parenchyma. Both high baseline levels of IL-6 and SAA on hospital admission were highly correlated with a later ventilatory requirement and mortality, independent of hospital stay. Mortality was found to be significantly higher when the chest CT severity score was 3-4, compared with a severity score of 0-2 (p < 0.0001). Conclusions: at the admission stage, IL-6 and SAA are useful markers for COVID-19 patients with CKD.

Serum and Urinary Biomarkers in COVID-19 Patients with or without Baseline Chronic Kidney Disease

In a prospective, observational, non-interventional, single-center study, we assessed various plasma and urinary biomarkers of kidney injury (neutrophil gelatinase-associated Lipocain [NGAL], kidney-injury molecule-1 [KIM-1], and interleukin-18 [IL-18]); inflammation (IL-6, C-reactive protein [CRP]); plus angiotensin converting enzyme 2 (ACE2) in 120 COVID-19 patients (of whom 70 had chronic kidney disease (CKD) at emergency-department (ED) admission). Our aim was to correlate the biomarkers with the outcomes (death, acute kidney injury [AKI]). All patients had received a chest-CT scan at admission to calculate the severity score (0–5). Biomarkers were also assessed in healthy volunteers and non-COVID-19-CKD patients. These biomarkers statistically differed across subgroups, i.e., they were significantly increased in COVID-19 patients, except for urinary (u)KIM1 and uIL-18. Amongst the biomarkers, only IL-6 was independently associated with mortality, along with AKI and not using remdesivir. Regarding the prediction of AKI, only IL-6 and uKIM1 were significantly elevated in patients presenting with AKI. However, AKI could not be predicted. Having high baseline IL-6 levels was associated with subsequent ventilation requirement and death. The mortality rate was almost 90% when the chest CT-scan severity score was 3 or 4 vs. 6.8% when the severity score was 0–2 (p < 0.0001).

Renin-angiotensin-aldosterone system blockers in Bulgarian COVID-19 patients with or without chronic kidney disease

When angiotensin-converting enzyme inhibitor/angiotensin receptor blocker-treated patients present with SARS-CoV-2 infection there is a debate to know whether renin-angiotensin-aldosterone (RAAS) blockers should be stopped or not. We conducted a prospective observational study in Bulgarian COVID-19-infected patients with or without chronic kidney disease (CKD) to assess whether maintenance RAAS blocker therapy has an impact on SARS-CoV-2 infection and its complications. We included 120 in-patient COVID-19 subjects, of whom 70 had CKD and 50 had normal renal function. A total of 30% of the patients (total number of 36 patients, 21 females) were receiving RAAS therapy at admission and it was maintained throughout hospitalization. The overall mortality was 19.2% (23 patients); there was no significant difference across the 2 groups (P-value = .21), except in RAAS blockers-treated hypertensive patients who had a significantly lower mortality as compared to non-RAAS-blockers-treated hypertensive patients (P = .04). Regarding subsequent intensive-care unit admission, there were 50% less patients in the RAAS group (4 out of 36, i.e., 11%) as compared to 19 out of 84 from the non-RAAS group, that is, 22.6% (P = .29). Overall, 37 patients developed acute kidney injury (any stage by KDIGO); of them 14 (37.8%) were receiving RAAS blockers. Acute kidney injury was not significantly associated with the use of RAAS blockers (P-value = .28). Likewise, both in non-CKD and in CKD patients the use of RAAS blockers did not have an impact on renal function recovery after SARS-CoV-2 infection. Finally, regarding RAAS blockers and the biological parameters outcome only D-dimers were significantly lower at the follow-up as compared to that in non-RAAS blocker treated patients. RAAS blockers benefited patients with hypertension by lowering mortality rate. Other than that, RAAS blocker therapy continuation during SARS-CoV-2 infection in CKD and non-CKD patients had no significant impact upon major outcomes.