From past to present: Exploring COVID-19 in Qatar's hemodialysis population across Omicron dominant and pre-Omicron periods

COVID-19 carries a high risk of morbidity and mortality in dialysis patients. Multiple SARS-CoV-2 variants have been identified since the start of the COVID-19 pandemic. The current study aimed to compare the incidence and outcomes of the COVID-19 Omicron dominant period versus other pre-Omicron period in hemodialysis patients. In this observational, analytical, retrospective, nationwide study, we reviewed adult chronic hemodialysis patients between March 1, 2020, and January 31, 2022. Four hundred twenty-one patients had COVID-19 during the study period. The incidence of COVID-19 due to the Omicron dominant period was significantly higher than other pre-Omicron period (30.3% vs. 18.7%, P<0.001). In contrast, the admission rate to ICU was significantly lower in the Omicron dominant period than in the pre-Omicron period (2.8% vs. 25%, P<0001) but with no significant difference in ICU length of stay. The mortality rate was lower in the Omicron dominant period compared to the pre-Omicron period (2.4% vs. 15.5%, P<0.001). Using multivariate analysis, older age [OR 1.093 (95% CI 1.044-1.145); P<0.0001] and need for mechanical ventilation [OR 70.4 (95% CI 20.39-243.1); P<0.0001] were identified as two independent risk factors for death in hemodialysis patients with COVID-19. In Conclusion, the COVID-19 Omicron variant had a higher incidence and lower morbidity and mortality than pre-Omicron period in our hemodialysis population.

Effectiveness of Messenger RNA Vaccines against SARS-CoV-2 Infection in Hemodialysis Patients: A Case-Control Study

Patients with end-stage kidney disease (ESKD) are at increased risk for SARS-CoV-2 infection and its complications compared with the general population. Several studies evaluated the effectiveness of COVID-19 vaccines in the dialysis population but showed mixed results. The aim of this study was to determine the effectiveness of COVID-19 mRNA vaccines against confirmed SARS-CoV-2 infection in hemodialysis (HD) patients in the State of Qatar. We included all adult ESKD patients on chronic HD who had at least one SARS-CoV-2 PCR test done after the introduction of the COVID-19 mRNA vaccines on 24 December 2020. Vaccinated patients who were only tested before receiving any dose of their COVID-19 vaccine or within 14 days after receiving the first vaccine dose were excluded from the study. We used a test-negative case−control design to determine the effectiveness of the COVID-19 vaccination. Sixty-eight patients had positive SARS-CoV-2 PCR tests (cases), while 714 patients had negative tests (controls). Ninety-one percent of patients received the COVID-19 mRNA vaccine. Compared with the controls, the cases were more likely to be older (62 ± 14 vs. 57 ± 15, p = 0.02), on dialysis for more than one year (84% vs. 72%, p = 0.03), unvaccinated (46% vs. 5%, p < 0.0001), and symptomatic (54% vs. 21%, p < 0.0001). The effectiveness of receiving two doses of COVID-19 mRNA vaccines against confirmed SARS-CoV-2 infection was 94.7% (95% CI: 89.9−97.2) in our HD population. The findings of this study support the importance of using the COVID-19 mRNA vaccine in chronic HD patients to prevent SARS-CoV-2 infection in such a high-risk population.

Risk factors associated with chronic kidney disease progression: Long-term retrospective analysis from Qatar

Introduction: The risk factors influencing the natural course of chronic kidney disease (CKD) are complex and heterogeneous. Recognizing the factors associated with CKD progression can enable the identification of high-risk patients for more intensive treatment.

Patients and methods: A retrospective evaluation of CKD patients was performed under follow-up between January 1, 2001 and December 31, 2016 at a tertiary health care center.

Results: Among 5370 screened patients, 1020 patients with complete data were included in the analysis. The median follow-up period for the studied patients was 9.3 years. Based on the analysis, 120 (11.8%) patients had reached end-stage kidney disease “ESKD” or death. The study revealed that the risk factors associated with reaching ESKD and/or death using Kaplan–Meier survival curve and log rank test included higher hemoglobin A1c among diabetic patients, higher grade of proteinuria, and non use of renin-angiotensin system blockers. The patients with CKD progression constituted 77.2% of all CKD patients. The study findings indicated that older age, Arab ethnicity, smoking habit, diabetes mellitus and hypertension (presumed as original kidney diseases) are among the significant risk factors associated with a further decline of the estimated glomerular filtration rate (eGFR) and further CKD progression.

Conclusion: This study summarized the demographic and clinical risk factors associated with CKD progression and patients’ outcomes among a unique and heterogeneous population in the state of Qatar. Intensive treatment of modifiable risk factors could be of value in halting the progression of CKD. However, prospective studies are warranted to confirm our findings.

Prevalence of coronavirus disease 2019 in a multiethnic cohort of patients with autoimmune rheumatic diseases in Qatar

Background: Autoimmune rheumatic diseases (ARDs) are characterized by immune dysfunction and associated with an increased risk of infections, which were of significant concern during the coronavirus disease 2019 (COVID-19) pandemic. Variable rates of COVID-19 incidence have been reported in patients with ARDs; however, the true effect of this infection on this patient population is still unclear. We, therefore, aimed to evaluate the COVID-19 prevalence among a multiethnic cohort of patients with ARDs in Qatar.

Material and Methods: We used telephonic surveys to collect demographic and clinical information of patients with ARD in Qatar between April 1 and July 31, 2020, including any close contact with a COVID-19 case at home or work and polymerase chain reaction (PCR)-confirmed COVID-19 diagnosis. An electronic medical records review was conducted to verify pertinent data collected through the surveys. Prevalence with 95% confidence interval (CI), Student's t-tests, and chi-square/Fisher's exact tests were used for univariate analyses, whereas multivariate logistic regression was used to identify factors associated with COVID-19.

Results: The study included 700 patients with ARD (mean age, 43.2 ± 12.3 years), and 73% were female. Until July 2020, 75 (11%, 95% CI 9%–13%) patients had COVID-19. Factors associated with COVID-19 included being a man (adjusted odds ratio [aOR] 2.56, 95% CI 1.35–4.88, p = 0.01) and having close contact with a COVID-19 case (aOR 27.89, 95% CI 14.85–52.38, p = 0.01). Disease severity and rheumatic medications had no significant association with the odds of contracting COVID-19. In the 86 patients with ARD having close contact, the frequency of hydroxychloroquine utilization was lower in patients who contracted COVID-19 than in those who did not (35% vs 72.5%, p = 0.01).

Conclusions: In Qatar, patients with ARDs had an overall higher prevalence of COVID-19 than global estimates. Being male and having close contact with a COVID-19 case were strongly associated with COVID-19 as reported globally. The presence of comorbid conditions, disease-specific factors, and rheumatic medications had no significant effect on the risk of COVID-19 in our study suggesting alternative mechanisms to the increased prevalence.

Validation of a noninvasive prognostic signature for allograft failure following BK virus associated nephropathy

Identifying kidney transplant recipients at risk for graft failure following BK virus nephropathy (BKVN) may allow personalization of therapy. We have reported that a noninvasive composite signature of urinary cell level of plasminogen activator inhibitor-1(PAI-1) mRNA and serum creatinine level, measured at the time of BKVN diagnosis, is prognostic of graft failure. In this investigation, we determined whether the composite signature is prognostic of graft failure in an independent cohort of 25 patients with BKVN. Of the 25 patients, 8 developed graft failure and 17 did not. We measured urinary cell levels of PAI-1 mRNA, 18S rRNA, and BKV VP1 mRNA at the time of BKVN diagnosis and evaluated clinical parameters including Banff pathology scores, acute rejection, and graft function. The area under the receiver operating characteristic curve for the noninvasive composite signature was 0.95 (P < .001) for prognosticating graft failure. The previously reported threshold of -0.858 predicted graft failure with a sensitivity of 75% and a specificity of 94%. Our current study validates the use of composite signature and the threshold of -0.858 to identify those at risk for graft failure following BKVN diagnosis, and supports future studies utilizing the composite signature score to personalize treatment of BKVN.

Restructuring nephrology services to combat COVID-19 pandemic: Report from a Middle Eastern country

Coronavirus disease 2019 has spread across the world and has been classified as a pandemic. It has overwhelmed the healthcare systems. Specifically, it has overstretched the intensive care units and renal replacement therapy services in many countries. In this paper, we discuss the reconfiguration of nephrology services in the State of Qatar during the current pandemic. We highlight the key strategies that have been implemented to ensure that renal replacement therapy capacity is not constrained in either the intensive care or ambulatory setting. Some innovative approaches for the safe delivery of ambulatory care to dialysis and kidney transplant patients are also discussed.

Prediabetes and older age increase the risk of post-transplantation diabetes mellitus: Qatar experience

Post-transplantation diabetes mellitus (PTDM) is a major complication in kidney transplant recipients leading to reduced allograft and patient survival. Given the high prevalence of diabetes in Qatar, which is twice the global average, we were interested in determining the incidence of PTDM, identifying risk factors, and comparing clinical outcomes in kidney transplant recipients with and without diabetes. We retrospectively followed up 191 adult kidney allograft recipients transplanted between January 1, 2012, and December 31, 2016, for a median of 41 months. A total of 76 patients (40%) had pre-existing diabetes. A total of 39 patients developed PTDM during follow-up; they represent 34% of patients who did not have diabetes prior to transplantation. Two thirds of PTDM occurred within 3-6 months post-transplantation. Prediabetes before transplant [OR = 6.07 (1.24-29.74), P = .026] older recipient's age at the time of transplantation [OR = 1.10 (1.00-1.20), P = .039] and average fasting blood sugar during 3-6 months post-transplant [OR = 1.06 (1.01-1.11), P = .010] were independently associated with PTDM. Patient and kidney allograft survival rates exceeded 97% in all groups. The incidence of PTDM in kidney transplant recipients living in Qatar is high. Older age and prediabetes are independent risk factors for developing PTDM.

Acute Rejection, Kidney Allograft Function, and Graft Survival in Patients with Circulating Pre-Transplant IgG Antibodies Directed Against Donor HLA-A, -B, or -C Locus Determined Antigens

The relationship between circulating pre-transplant immunoglobulin G (IgG) antibodies to donor human leukocyte antigen (HLA) -C locus determined antigens alone and acute rejection, kidney allograft function, and graft survival is not fully defined. Also, the impact of circulating pre-transplant IgG antibodies to donor HLA-C locus antigens alone on these outcomes has not been compared with the impact of circulating pre-transplant IgG antibodies to donor HLA-A or -B locus antigens. We conducted a retrospective review of records of 1252 kidney allograft recipients transplanted at our center between January 2010 and January 2016 to identify patients with circulating pre-transplant IgG antibodies directed at kidney donor HLA-A, -B, or -C locus determined antigens. Antibodies were detected and reported using the LABScreen Single Antigen Bead assay with microbeads coated with single HLA class I antigens. Pre-transplant and post-transplant data were collected and the graft outcomes of 16 kidney graft recipients with antibodies to HLA-C locus antigens were compared to the outcomes in 56 recipients with antibodies to HLA-A or -B locus determined antigens. The one-year acute rejection rate was 6% in those with donor-specific antibodies (DSA) to HLA-C locus antigens and 20% in those with DSA to HLA-A or -B locus antigens. The graft survival rate was 100% in those with DSA to HLA-C locus antigens and 95% in those with DSA to HLA-A or -B locus antigens. None of the numerical differences were statistically significant (p>0.05). The presence of circulating pre-transplant IgG antibodies directed at kidney donor HLA-C locus antigens alone may not be associated with an increased risk of acute rejection or a decreased graft survival rate. Our observations support the concept that circulating pre-transplant IgG antibodies directed at kidney donor HLA-C locus antigens alone do not negatively impact kidney allograft outcomes and that the mean fluorescence intensities of the antibodies directed at HLA-C locus alone should not be used to list unacceptable HLA-C locus antigens for kidney allocation. A study with a larger cohort is needed to investigate our hypothesis.