Biopsy-proven BK virus nephropathy in renal transplant recipients: A multi-central study from Turkey (BK-TURK STUDY).

AIM: BK polyomavirus infection is a challenging complication of renal transplantation. The management is not standardized and is based on reports from transplantation centers' experiences, usually with small sample sizes. Therefore, we aimed to present our countrywide experience with BK virus nephropathy (BKVN) in renal transplant recipients. MATERIALS AND METHODS: Our study was carried out with the participation of 30 transplantation centers from all regions of Turkey. Only cases with allograft biopsy-proven BKVN were included in the study. RESULTS: 13,857 patients from 30 transplantation centers were screened, and 207 BK nephropathy cases were included. The mean age was 46.4 ±  13.1 years, and 146 (70.5%) patients were male. The mean time to diagnosis of BK nephropathy was 15.8 ± 22.2 months after transplantation. At diagnosis, the mean creatinine level was 1.8 ±  0.7 mg/dL, and the mean estimated glomerular filtration rate was 45.8 ± 19.6 mL/min/1.73m2. In addition to dose reduction or discontinuation of immunosuppressive drugs, 18 patients were treated with cidofovir, 11 patients with leflunomide, 17 patients with quinolones, 15 patients with intravenous immunoglobulin (IVIG), 5 patients with cidofovir plus IVIG, and 12 patients with leflunomide plus IVIG. None of the patients receiving leflunomide or leflunomide plus IVIG had allograft loss. During follow-up, allograft loss occurred in 32 (15%) out of 207 patients with BK nephropathy. CONCLUSION: BKVN is still a frequent cause of allograft loss in kidney transplantation and is not fully elucidated. The results of our study suggest that leflunomide treatment is associated with more favorable allograft outcomes.

Thirst intensity survey in ADPKD patients.

INTRODUCTION: With increased fluid intake and tolvaptan treatment, the growth rate of cysts can be theoretically decelerated in autosomal polycystic kidney disease. In this prospective study, it was planned to evaluate thirst sensation in these patients and the parameters affecting its intensity. METHODS: Forty-one ADPKD patients on tolvaptan and 40 ADPKD patients not on tolvaptan as the control group were evaluated for thirst distress sensation and intensity. The feeling of thirst and the discomfort caused by excessive fluid intake was assessed with Thirst Distress Scale-HF 12 questions (60/12). Thirst intensity was evaluated with a 100 mm visual scale. RESULTS: Of the whole group, 35.8% (29) were males, and 64.2% (52) were females. The mean age of the tolvaptan group was 39.17 ± 9.35 years and for the control group, it was 41.95 ± 12.29 years. There was a negative correlation between the thirst distress score of the patients and an increase in creatinine level after a year of tolvaptan treatment (r = - 0.335, p = 0.035). The patients not taking thiazide had higher thirst intensity scores (p = 0.004). There was no impact of tolvaptan dosage, total kidney volume, serum sodium, urinary osmolarity or eGFR on thirst distress and thirst intensity scores. DISCUSSION/CONCLUSION: Only thiazide co-treatment had a positive impact on thirst distress and intensity when given tolvaptan. Thirst Distress Scale for ADPKD patients can be used to classify patients before and during tolvaptan treatment.

The Clinical Frailty Scale as a triage tool for ICU admission of dialysis patients with COVID-19: an ERACODA analysis.

BACKGROUND: Several guidelines recommend using the Clinical Frailty Scale (CFS) for triage of critically ill coronavirus disease 2019 (COVID-19) patients. This study evaluates the impact of CFS on intensive care unit (ICU) admission rate and hospital and ICU mortality rates in hospitalized dialysis patients with COVID-19. METHODS: We analysed data of dialysis patients diagnosed with COVID-19 from the European Renal Association COVID-19 Database. The primary outcome was ICU admission rate and secondary outcomes were hospital and ICU mortality until 3 months after COVID-19 diagnosis. Cox regression analyses were performed to assess associations between CFS and outcomes. RESULTS: A total of 1501 dialysis patients were hospitalized due to COVID-19, of whom 219 (15%) were admitted to an ICU. The ICU admission rate was lowest (5%) in patients >75 years of age with a CFS of 7-9 and highest (27%) in patients 65-75 years of age with a CFS of 5. A CFS of 7-9 was associated with a lower ICU admission rate than a CFS of 1-3 [relative risk 0.49 (95% confidence interval 0.27-0.87)]. Overall, mortality at 3 months was 34% in hospitalized patients, 65% in ICU-admitted patients and highest in patients >75 years of age with a CFS of 7-9 (69%). Only 9% of patients with a CFS ≥6 survived after ICU admission. After adjustment for age and sex, each CFS category ≥4 was associated with higher hospital and ICU mortality compared with a CFS of 1-3. CONCLUSIONS: Frail dialysis patients with COVID-19 were less frequently admitted to the ICU. Large differences in mortality rates between fit and frail patients suggest that the CFS may be a useful complementary triage tool for ICU admission in dialysis patients with COVID-19.

Characteristics and outcomes of hospitalised older patients with chronic kidney disease and COVID-19: A multicenter nationwide controlled study.

OBJECTIVE: Older adults with co-morbidities have been reported to be at higher risk for adverse outcomes of coronavirus disease 2019 (COVID-19). The characteristics of COVID-19 in older patients and its clinical outcomes in different kidney disease groups are not well known. METHODS: Data were retrieved from a national multicentric database supported by Turkish Society of Nephrology, which consists of retrospectively collected data between 17 April 2020 and 31 December 2020. Hospitalised patients aged 18 years or older with confirmed COVID-19 diagnosis suffering from stage 3-5 chronic kidney disease (CKD) or on maintenance haemodialysis (HD) treatment were included in the database. Non-uraemic hospitalised patients with COVID-19 were also included as the control group. RESULTS: We included 879 patients [388 (44.1%) female, median age: 63 (IQR: 50-73) years]. The percentage of older patients in the CKD group was 68.8% (n = 188/273), in the HD group was 49.0% (n = 150/306) and in the control group was 30.4% (n = 70/300). Co-morbidities were higher in the CKD and HD groups. The rate of presentation with severe-critical disease was higher in the older CKD and HD groups (43.6%, 55.3% and 16.1%, respectively). Among older patients, the intensive care unit (ICU) admission rate was significantly higher in the CKD and HD groups than in the control group (38.8%, 37.3% and 15.7%, respectively). In-hospital mortality or death and/or ICU admission rates in the older group were significantly higher in the CKD (29.3% and 39.4%) and HD groups (26.7% and 30.1%) compared with the control group (8.6% and 17.1%). In the multivariate analysis, in-hospital mortality rates in CKD and HD groups were higher than control group [hazard ratio (HR): 4.33 (95% confidence interval [CI]: 1.53-12.26) and HR: 3.09 (95% CI: 1.04-9.17), respectively]. CONCLUSION: Among older COVID-19 patients, in-hospital mortality is significantly higher in those with stage 3-5 CKD and on maintenance HD than older patients without CKD regardless of demographic characteristics, co-morbidities, clinical and laboratory data on admission.

Impact of hospital-acquired acute kidney injury on Covid-19 outcomes in patients with and without chronic kidney disease: a multicenter retrospective cohort study

Background/aim: Hospital-acquired acute kidney injury (HA-AKI) may commonly develop in Covid-19 patients and is expected to have higher mortality. There is little comparative data investigating the effect of HA-AKI on mortality of chronic kidney disease (CKD) patients and a control group of general population suffering from Covid-19. Materials and methods: HA-AKI development was assessed in a group of stage 3­5 CKD patients and control group without CKD among adult patients hospitalized for Covid-19. The role of AKI development on the outcome (in-hospital mortality and admission to the intensive care unit [ICU]) of patients with and without CKD was compared. Results: Among 621 hospitalized patients (age 60 [IQR: 47­73]), women: 44.1%), AKI developed in 32.5% of the patients, as stage 1 in 84.2%, stage 2 in 8.4%, and stage 3 in 7.4%. AKI developed in 48.0 % of CKD patients, whereas it developed in 17.6% of patients without CKD. CKD patients with HA-AKI had the highest mortality rate of 41.1% compared to 14.3% of patients with HA-AKI but no CKD (p < 0.001). However, patients with AKI+non-CKD had similar rates of ICU admission, mechanical ventilation, and death rate to patients with CKD without AKI. Adjusted mortality risks of the AKI+non-CKD group (HR: 9.0, 95% CI: 1.9­44.2) and AKI+CKD group (HR: 7.9, 95% CI: 1.9­33.3) were significantly higher than that of the non-AKI+non-CKD group. Conclusion: AKI frequently develops in hospitalized patients due to Covid-19 and is associated with high mortality. HA-AKI has worse outcomes whether it develops in patients with or without CKD, but the worst outcome was seen in AKI+CKD patients.

COVID-19-related mortality in kidney transplant and dialysis patients: results of the ERACODA collaboration.

BACKGROUND: Patients on kidney replacement therapy comprise a vulnerable population and may be at increased risk of death from coronavirus disease 2019 (COVID-19). Currently, only limited data are available on outcomes in this patient population. METHODS: We set up the ERACODA (European Renal Association COVID-19 Database) database, which is specifically designed to prospectively collect detailed data on kidney transplant and dialysis patients with COVID-19. For this analysis, patients were included who presented between 1 February and 1 May 2020 and had complete information available on the primary outcome parameter, 28-day mortality. RESULTS: Of the 1073 patients enrolled, 305 (28%) were kidney transplant and 768 (72%) dialysis patients with a mean age of 60 ± 13 and 67 ± 14 years, respectively. The 28-day probability of death was 21.3% [95% confidence interval (95% CI) 14.3-30.2%] in kidney transplant and 25.0% (95% CI 20.2-30.0%) in dialysis patients. Mortality was primarily associated with advanced age in kidney transplant patients, and with age and frailty in dialysis patients. After adjusting for sex, age and frailty, in-hospital mortality did not significantly differ between transplant and dialysis patients [hazard ratio (HR) 0.81, 95% CI 0.59-1.10, P = 0.18]. In the subset of dialysis patients who were a candidate for transplantation (n = 148), 8 patients died within 28 days, as compared with 7 deaths in 23 patients who underwent a kidney transplantation <1 year before presentation (HR adjusted for sex, age and frailty 0.20, 95% CI 0.07-0.56, P < 0.01). CONCLUSIONS: The 28-day case-fatality rate is high in patients on kidney replacement therapy with COVID-19 and is primarily driven by the risk factors age and frailty. Furthermore, in the first year after kidney transplantation, patients may be at increased risk of COVID-19-related mortality as compared with dialysis patients on the waiting list for transplantation. This information is important in guiding clinical decision-making, and for informing the public and healthcare authorities on the COVID-19-related mortality risk in kidney transplant and dialysis patients.

Mortality analysis of COVID-19 infection in chronic kidney disease, haemodialysis and renal transplant patients compared with patients without kidney disease: a nationwide analysis from Turkey.

BACKGROUND: Chronic kidney disease (CKD) and immunosuppression, such as in renal transplantation (RT), stand as one of the established potential risk factors for severe coronavirus disease 2019 (COVID-19). Case morbidity and mortality rates for any type of infection have always been much higher in CKD, haemodialysis (HD) and RT patients than in the general population. A large study comparing COVID-19 outcome in moderate to advanced CKD (Stages 3-5), HD and RT patients with a control group of patients is still lacking. METHODS: We conducted a multicentre, retrospective, observational study, involving hospitalized adult patients with COVID-19 from 47 centres in Turkey. Patients with CKD Stages 3-5, chronic HD and RT were compared with patients who had COVID-19 but no kidney disease. Demographics, comorbidities, medications, laboratory tests, COVID-19 treatments and outcome [in-hospital mortality and combined in-hospital outcome mortality or admission to the intensive care unit (ICU)] were compared. RESULTS: A total of 1210 patients were included [median age, 61 (quartile 1-quartile 3 48-71) years, female 551 (45.5%)] composed of four groups: control (n = 450), HD (n = 390), RT (n = 81) and CKD (n = 289). The ICU admission rate was 266/1210 (22.0%). A total of 172/1210 (14.2%) patients died. The ICU admission and in-hospital mortality rates in the CKD group [114/289 (39.4%); 95% confidence interval (CI) 33.9-45.2; and 82/289 (28.4%); 95% CI 23.9-34.5)] were significantly higher than the other groups: HD = 99/390 (25.4%; 95% CI 21.3-29.9; P < 0.001) and 63/390 (16.2%; 95% CI 13.0-20.4; P < 0.001); RT = 17/81 (21.0%; 95% CI 13.2-30.8; P = 0.002) and 9/81 (11.1%; 95% CI 5.7-19.5; P = 0.001); and control = 36/450 (8.0%; 95% CI 5.8-10.8; P < 0.001) and 18/450 (4%; 95% CI 2.5-6.2; P < 0.001). Adjusted mortality and adjusted combined outcomes in CKD group and HD groups were significantly higher than the control group [hazard ratio (HR) (95% CI) CKD: 2.88 (1.52-5.44); P = 0.001; 2.44 (1.35-4.40); P = 0.003; HD: 2.32 (1.21-4.46); P = 0.011; 2.25 (1.23-4.12); P = 0.008), respectively], but these were not significantly different in the RT from in the control group [HR (95% CI) 1.89 (0.76-4.72); P = 0.169; 1.87 (0.81-4.28); P = 0.138, respectively]. CONCLUSIONS: Hospitalized COVID-19 patients with CKDs, including Stages 3-5 CKD, HD and RT, have significantly higher mortality than patients without kidney disease. Stages 3-5 CKD patients have an in-hospital mortality rate as much as HD patients, which may be in part because of similar age and comorbidity burden. We were unable to assess if RT patients were or were not at increased risk for in-hospital mortality because of the relatively small sample size of the RT patients in this study.

Sodium bicarbonate is a potential alternative to classic heparin as a lock solution for non-tunneled dialysis catheters: a result from the prospective randomized BicarbLock trial.

OBJECTIVE: Temporary vascular access is mandatory for acute hemodialysis. Heparin lock solution is the standard of care worldwide. Many lock solutions were studied in terms of thrombosis and catheter-related infection prevention, but none replaced heparin as a standard measure. Our main aim is to investigate the effectiveness of sodium bicarbonate (NaHCO3), a ubiquitous and cheap option as a catheter lock solution, in comparison with traditionally used heparin in non-tunneled hemodialysis catheters. METHODS: We conducted our prospective study between March 2021 and March 2022. Our study included 441 patients > 18 years old who needed either femoral or jugular non-tunneled dialysis catheters. Patients were assigned to either heparin (5000 IU/ml) or 8.4% sodium bicarbonate on a consecutive basis. Basic characteristics and information regarding catheters, dialysis sessions, and complications were recorded. We divided patients according to the catheter insertion site as well as the lock solution. RESULTS: We analyzed 426 patients divided into four groups: jugular heparin (n = 113), jugular bicarbonate (n = 113), femoral heparin (n = 113), and femoral bicarbonate (n = 100). Basal characteristics were similar for all groups. The mean time to last effective dialysis in our institution was 10.7 ± 12.1 days for heparin vs 11.5 ± 10.8 days for the bicarbonate group. 25 (5.9%) patients had some kind of blood flow problems (13 in the heparin and 12 in the bicarbonate group). There was no significant difference in terms of catheter malfunction among groups (p = 0.50). Out of these 25 cases, only 12 (7 in heparin and 5 in the bicarbonate arm) had catheter dysfunction (p = 0.386). Sixty-four patients (28%) with jugular catheters were discharged with patent catheters and continued their dialysis in other facilities. CONCLUSION: Sodium bicarbonate is as effective as classic unfractionated heparin in preventing catheter lumen thrombosis with a comparable incidence of catheter-related complications. Furthermore, it is a cost-effective option that can be used confidently, especially when heparin is contraindicated. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT04772209 (26.02.2021).

Resilience and challenges of peritoneal dialysis survivors in the aftermath of the 2023 Kahramanmaras earthquake.

INTRODUCTION: Peritoneal dialysis (PD) remains understudied in disaster nephrology. This retrospective multicenter study explores the experiences of PD survivors following the February 6, 2023, Kahramanmaras Earthquake. METHODS: Adult PD patients from 11 affected cities were analyzed to assess challenges faced during and postearthquake, alongside clinical outcomes. RESULTS: Among 101 participants (median age: 45 years, median PD duration: 24 months), 57 were female, with 79 on continuous ambulatory PD. Challenges included power outages and water shortages, with primary shelter in kin's houses (33%) and homes (28%). Twelve patients experienced PD program delays, and three lacked assistance postdisaster. Sixteen patients changed PD modalities, with seven experiencing postearthquake peritonitis. Clinical parameters remained stable, except for a slight decrease in hemoglobin levels. CONCLUSION: Despite challenges, PD survivors exhibited resilience, highlighting the importance of addressing peritonitis and unusual pathogens in disaster preparedness initiatives.

Does Monocyte Chemoattractant Protein-1 Levels Determine the Prognosis of Covid-19 Disease in Kidney Transplant Recipients?

BACKGROUND: In the normal population, a high monocyte chemoattractant protein (MCP-1) level is an important biomarker for the progression of COVID-19. This study investigated whether MCP-1 level can determine the disease prognosis in kidney transplant (KT) patients with COVID-19. METHODS: A total of 89 patients, including 49 KT patients (group 1) diagnosed with COVID-19 who required hospitalization, and 40 KT patients who did not have COVID-19 disease (group 2), were included. Demographic characteristics and laboratory results of the patients were recorded. The serum reserved for MCP-1 was stored at -80°C and studied blindly by a single microbiologist at the end of the study. RESULTS: While the mean age of the patients was 51.0 years (40.0-59.50) in group 1, it was 48.0 years (40.75-54.75) in group 2 (P > .05). In terms of the female sex, it was 36 (73.5%) and 27 (67.5%) in group 1 and group 2, respectively (P > .05). Similarly, there was no significant difference between the 2 groups regarding primary disease and basal graft function (P > .05). There was a statistically significant difference in inflammation indicators in group 1 compared with group 2 (P < .05). A correlation was found between inflammation indicators and COVID-19 (P < .05). However, no significant correlation was detected between COVID-19 disease and MCP-1 levels in both groups (P > .05). Also, according to basal MCP-1 levels, we did not find a significant difference between survival and nonsurvival patients (164.0 pg/mL [146.0-202.0] vs 156.0 pg/mL [143.0-173.0], respectively (P > .05). CONCLUSION: Monocyte chemoattractant protein, an indicator of inflammation, was not found to predict the prognosis of COVID-19 disease in kidney recipients.

Can Fetuin-A Deficiency Predict the Severity of COVID-19 Disease in Kidney Transplant Recipients?

BACKGROUND: This study aims to investigate whether fetuin A deficiency predicts the prognosis of COVID-19 disease in kidney transplant recipients (KTRs). METHOD: The study was conducted on 35 hospitalized KTRs with COVID-19 pneumonia between November 2020 and June 2021. Serums were collected for fetuin-A measurement at admission and after six months of follow-up. The demographic and laboratory data of the patients were recorded and analyzed with the appropriate statistical method. RESULTS: A total of 35 KTRs, 23 of which (65.7%) were men, were included in the study. The mean age of the patients was 51.6 ± 14.0 years. Seventeen (48.6%) patients had severe disease criteria and required intensive care (ICU) support. Biopsy-proven acute rejection developed in 6 (17.1%) patients in the follow-up. At admission, the median fetuin-A value was 173.5 mcg/mL (143.5-199.25) in the moderate disease group and 126.0 mcg/mL (89.4-165.5) in the severe patient group (p = 0.005). While the Median fetuin-A value at the time of diagnosis was 173.5 mcg/mL (143.5-199.25), and in the 6th month was 208 mcg/mL [184-229] (p<0.001). By ROC analysis, the effect of serum fetuin-A level in predicting the severity of COVID-19 disease was significant (AUC: 0.771, p = 0.006, 95% CI: 0.615-0.927). When serum fetuin-A cut-off value was taken as 138 mcg/mL to determine disease severity, it was shown to have 83.3% sensitivity and 64.7% specificity. CONCLUSIONS: Serum fetuin-A level can predict disease severity in kidney transplant recipients in the presence of active COVID-19 disease.

Association of obesity with 3-month mortality in kidney failure patients with COVID-19.

Background: In the general population with coronavirus disease 2019 (COVID-19), obesity is associated with an increased risk of mortality. Given the typically observed obesity paradox among patients on kidney function replacement therapy (KFRT), especially dialysis patients, we examined the association of obesity with mortality among dialysis patients or living with a kidney transplant with COVID-19. Methods: Data from the European Renal Association COVID-19 Database (ERACODA) were used. KFRT patients diagnosed with COVID-19 between 1 February 2020 and 31 January 2021 were included. The association of Quetelet's body mass index (BMI) (kg/m2), divided into: <18.5 (lean), 18.5-24.9 (normal weight), 25-29.9 (overweight), 30-34.9 (obese I) and ≥35 (obese II/III), with 3-month mortality was investigated using Cox proportional-hazards regression analyses. Results: In 3160 patients on KFRT (mean age: 65 years, male: 61%), 99 patients were lean, 1151 normal weight (reference), 1160 overweight, 525 obese I and 225 obese II/III. During follow-up of 3 months, 28, 20, 21, 23 and 27% of patients died in these categories, respectively. In the fully adjusted model, the hazard ratios (HRs) for 3-month mortality were 1.65 [95% confidence interval (CI): 1.10, 2.47], 1 (ref.), 1.07 (95% CI: 0.89, 1.28), 1.17 (95% CI: 0.93, 1.46) and 1.71 (95% CI: 1.27, 2.30), respectively. Results were similar among dialysis patients (N = 2343) and among those living with a kidney transplant (N = 817) (Pinteraction = 0.99), but differed by sex (Pinteraction = 0.019). In males, the HRs for the association of aforementioned BMI categories with 3-month mortality were 2.07 (95% CI: 1.22, 3.52), 1 (ref.), 0.97 (95% CI: 0.78. 1.21), 0.99 (95% CI: 0.74, 1.33) and 1.22 (95% CI: 0.78, 1.91), respectively, and in females corresponding HRs were 1.34 (95% CI: 0.70, 2.57), 1 (ref.), 1.31 (95% CI: 0.94, 1.85), 1.54 (95% CI: 1.05, 2.26) and 2.49 (95% CI: 1.62, 3.84), respectively. Conclusion: In KFRT patients with COVID-19, on dialysis or a kidney transplant, obesity is associated with an increased risk of mortality at 3 months. This is in contrast to the obesity paradox generally observed in dialysis patients. Additional studies are required to corroborate the sex difference in the association of obesity with mortality.

Clinical outcomes of COVID-19 in hemodialysis patients in the city of Zonguldak, Turkey.

PURPOSE: Patients on maintenance hemodialysis are vulnerable to viral infections like COVID-19 because of the low chance of obedience and complying with rules besides the need for transfer to distant dialysis facilities. We investigated the impact and clinical effect of treatment of COVID-19 in dialysis patients. METHODS: We included patients on maintenance hemodialysis at different healthcare facilities in Zonguldak city. With the diagnosis of the first infected HD case, all other patients who shared the same session were screened. Hospitalized and clinically confirmed cases were included. COVID-19 diagnosis was made based on clinical, biochemical along radiologic findings. RESULTS: 34 (F/M:19/15, mean age 62 ± 13.2 years, dialysis duration 66.9 ± 57.7 months, length of hospital stay 16.2 ± 7.9 days) were diagnosed with COVID-19 infection. The prevalence of COVID-19 was found to be 18.4% of our exposed population. 38.2% of our patients were initially diagnosed by CT screening while asymptomatic. 35.3% had a fever as the first presenting symptom. Lymphopenia was the most common laboratory finding. Except for one, all had at least one comorbidity. Out of 12 (35.3%) patients admitted to ICU 6(17.6%) died. The deceased patients were older, presented with lower serum albumin and lymphocyte count, and had higher CRP and fibrinogen levels. High CRP level on admission was the only significant predictor of mortality. CONCLUSION: Early detection will lower mortality. In this study, with a low prevalence of COVID-19, the importance of early screening of both symptomatic and asymptomatic patients was shown to be highly important. Further studies are still needed to find out the most appropriate medical management.

Characteristics and outcomes of acute kidney injury in hospitalized COVID-19 patients: A multicenter study by the Turkish society of nephrology.

BACKGROUND: Acute kidney injury (AKI) is common in coronavirus disease-2019 (COVID-19) and the severity of AKI is linked to adverse outcomes. In this study, we investigated the factors associated with in-hospital outcomes among hospitalized patients with COVID-19 and AKI. METHODS: In this multicenter retrospective observational study, we evaluated the characteristics and in-hospital renal and patient outcomes of 578 patients with confirmed COVID-19 and AKI. Data were collected from 34 hospitals in Turkey from March 11 to June 30, 2020. AKI definition and staging were based on the Kidney Disease Improving Global Outcomes criteria. Patients with end-stage kidney disease or with a kidney transplant were excluded. Renal outcomes were identified only in discharged patients. RESULTS: The median age of the patients was 69 years, and 60.9% were males. The most frequent comorbid conditions were hypertension (70.5%), diabetes mellitus (43.8%), and chronic kidney disease (CKD) (37.6%). The proportions of AKI stages 1, 2, and 3 were 54.0%, 24.7%, and 21.3%, respectively. 291 patients (50.3%) were admitted to the intensive care unit. Renal improvement was complete in 81.7% and partial in 17.2% of the patients who were discharged. Renal outcomes were worse in patients with AKI stage 3 or baseline CKD. The overall in-hospital mortality in patients with AKI was 38.9%. In-hospital mortality rate was not different in patients with preexisting non-dialysis CKD compared to patients without CKD (34.4 versus 34.0%, p = 0.924). By multivariate Cox regression analysis, age (hazard ratio [HR] [95% confidence interval (95%CI)]: 1.01 [1.0-1.03], p = 0.035], male gender (HR [95%CI]: 1.47 [1.04-2.09], p = 0.029), diabetes mellitus (HR [95%CI]: 1.51 [1.06-2.17], p = 0.022) and cerebrovascular disease (HR [95%CI]: 1.82 [1.08-3.07], p = 0.023), serum lactate dehydrogenase (greater than two-fold increase) (HR [95%CI]: 1.55 [1.05-2.30], p = 0.027) and AKI stage 2 (HR [95%CI]: 1.98 [1.25-3.14], p = 0.003) and stage 3 (HR [95%CI]: 2.25 [1.44-3.51], p = 0.0001) were independent predictors of in-hospital mortality. CONCLUSIONS: Advanced-stage AKI is associated with extremely high mortality among hospitalized COVID-19 patients. Age, male gender, comorbidities, which are risk factors for mortality in patients with COVID-19 in the general population, are also related to in-hospital mortality in patients with AKI. However, preexisting non-dialysis CKD did not increase in-hospital mortality rate among AKI patients. Renal problems continue in a significant portion of the patients who were discharged.