The Perioperative Anticoagulation Use for Surgery Evaluation (PAUSE) study prospectively evaluated a prespecified periprocedural-interruption strategy of direct oral anticoagulants (DOACs) among patients with atrial fibrillation. Logistic regression analyses were performed to identify clinical parameters associated with residual DOAC levels ≥30 ng/mL or ≥50 ng/mL. Patients undergoing low-bleed-risk procedures were more likely to have residual levels of ≥30 ng/mL and ≥50 ng/mL. For low-risk procedures, age ≥75 years, female sex, a creatinine clearance (CrCl) <50 mL/min, and an interruption of <36 hours were associated with a greater likelihood of levels ≥30 ng/mL, whereas age ≥75 years, female sex, a CrCl of <50 mL/min, and standard DOAC dosing were associated with levels ≥50 ng/mL. For high-risk procedures, weight of <70 kg, CrCl <50 mL/min, and standard DOAC dosing were associated with residual levels ≥30 ng/mL, whereas female sex was associated with levels ≥50 ng/mL. For low-risk procedures, apixaban was associated with a higher likelihood of levels ≥30 ng/mL as compared with dabigatran (P = .0019) and of levels ≥50 ng/mL when compared with rivaroxaban (P = .0003). For high-risk procedures, apixaban was marginally associated with a higher likelihood of residual levels ≥30 ng/mL when compared with dabigatran (P = .05), whereas rivaroxaban was associated with a higher likelihood of levels ≥30 ng/mL as compared with apixaban. Further study is required to determine whether adjustments to perioperative plans based on these clinical parameters could result in a lower risk of residual DOAC levels. The PAUSE trial was registered at www.clinicaltrials.gov as #NCT2228798.

Hemolytic uremic syndrome (HUS) is classically described as a triad of nonimmune hemolytic anemia, thrombocytopenia, and acute kidney injury. Atypical HUS (aHUS) is a rare variant of the disease, and it accounts for 5–10% of the cases. It has a poor prognosis, with a mortality rate exceeding 25% and a more than 50% chance of progressing into end-stage kidney disease (ESKD). Genetic or acquired dysregulation of the alternative complement pathway is highly implicated in the pathogenesis of aHUS. Multiple triggers for aHUS have been described in the literature, including pregnancy, transplantation, vaccination, and viral infections. Herein, we report a case of a previously healthy 38-year-old male who developed microangiopathic hemolytic anemia and severe kidney impairment one week after receiving the first dose of AstraZeneca SARS-CoV-2 vaccine. A diagnosis of aHUS was made after excluding other causes of thrombotic microangiopathies. Treatment with plasma exchange, prednisone, and rituximab (375 mg/m²) once weekly for four doses resulted in improvement of his hematological parameters. However, he progressed to ESKD.

Background: Data on outcomes of renal transplantation in the Kingdom of Saudi Arabia (KSA) is limited. We describe renal transplant experience in one of the largest referral centers for renal transplants in KSA. Methods: This is a retrospective cohort study of patients who underwent kidney transplantation at King Abdulaziz Medical City (KAMC) from January 2016 to July 31, 2019, with at least one year of follow-up post-transplantation. Results: One hundred ninety-four individuals were identified and included in the analysis. The mean age of the renal transplant cohort was 45 years with an average pre-transplant body mass index of 26.1 kg/m². The most common comorbidities were hypertension (77.3%) and diabetes mellitus (34.5%). The most common etiology of end-stage kidney disease (ESKD) was unknown (49.0%) followed by Lupus nephropathy (16.0%). Central venous catheters were the predominant dialysis access (56.2%). Living-related kidney donation was the commonest source of kidney transplantation (61.3%), followed by deceased donor renal transplantation (22.7%). Anti-thymocytes globulin (ATG) was the predominant induction agent (57.7%) and nearly all patients received tacrolimus-based maintenance immunosuppression. Mean serum creatinine at the time of discharge was 109 umol/l. Delayed graft function was observed in 6.7% of our patients. The most common medical complications were urinary tract infection (26.3%). Post-transplant surgical complications occurred at a low rate. Conclusion: Our study demonstrated a successful renal transplant experience among a relatively healthy cohort and identifies potential gaps, particularly the high rate of central venous catheters, the frequent lack of clear etiology of ESKD, the low rate of pre-emptive transplant, and deceased donors. Further studies are needed to evaluate and close these gaps.

Patients with end-stage kidney disease (ESKD) are disproportionately vulnerable to COVID-19 and its complications due to the older age and significant burden of comorbid conditions. Data about the impact of COVID-19 on the ESKD population in the Kingdom of Saudi Arabia is scarce, and this study aims to bridge this gap. This is a retrospective cohort study that included ESKD patients who were receiving either in-center hemodialysis (HD) or peritoneal dialysis (PD) for at least three months and were hospitalized due to COVID-19 at King Abdulaziz Medical City in Riyadh (KAMC) between March 2020 and March 2021. Of note, the in-center hemodialysis means that the patients come to the dialysis center three times per week to receive their dialysis sessions, as home hemodialysis is not available at our center. Multivariate logistic regression was performed to explore the association of clinical characteristics and laboratory parameters with ICU admission and mortality. A total of 104 patients were included in the analysis. The mean age was 62.6 (SD=17.4) years, 101 (97%) were on HD, predominantly through a central venous catheter (72%), and 53 patients (51%) were male. Patients with COVID-19 were either asymptomatic (42%) or had mild symptoms (37%), mainly cough and fever. At the time of admission, 37 patients (36%) had extrapulmonary symptoms, and 13 patients (12%) had altered mental status. Normal chest X-ray (48%), followed by bilateral lung infiltrates (24%), and unilateral lung infiltrate (11%) were the most common radiological findings. We did not observe any thromboembolic events. Twenty patients (19%) required ICU admission and 19 patients (18%) died during hospitalization. Predictors for in-hospital mortality were: 1) the need for inotropes (adjusted OR: 53.01, p=0.006), 2) age (adjusted OR: 1.07, p=0.019), and 3) C-reactive protein (CRP) level on admission (adjusted OR: 1.02, p=0.04). We did not find any strong predictor for ICU admission. Our study demonstrated that COVID-19 carries significant mortality and morbidity in the ESKD population. Age, inotropic support requirement and elevated CRP on admission predicted mortality in our population. The high rate of adverse outcomes of COVID-19 among ESRD patients calls for strict implementation of preventive measures, including vaccination, social distancing, and universal masking at the level of both the healthcare providers and patients. Further studies are needed to assess the association of COVID-19 and hypercoagulability ESKD population.

Overseas kidney transplantation is known to be associated with adverse outcomes. In this study, we aim to present a detailed analysis of our three years of experience with overseas kidney transplantation at one of the largest kidney transplant referral sites in the Kingdom of Saudi Arabia. A retrospective cohort study included patients who underwent kidney transplantation overseas and were subsequently followed up at King Abdulaziz Medical City from January 2016 to July 31, 2019. In addition, we compared the outcomes of the patients who underwent kidney transplantation overseas with a cohort of patients who were transplanted locally within the same period. Patients in both cohorts had to have at least one year of follow-up post-transplantation. We included a total of 51 patients who underwent kidney transplantation overseas. The mean age of the cohort was 44.7 years, and 69% were male. Almost 60% of the cohort had one or no comorbidity prior to transplant, with hypertension (84%) and diabetes mellitus (37%) being the leading comorbidities. The cause of end-stage kidney disease was unknown in 55% of our patients. In those who had an identifiable cause, lupus nephropathy and diabetes were the most common causes of kidney failure. In comparison with the locally transplanted cohort, no difference was detected between these groups in their baseline characteristics, type or number of comorbidities, medical or surgical complications postoperatively, and one-year mortality. However, we found that the graft rejection rate was significantly higher in patients transplanted overseas (OR=5.4, p<0.001). In addition, the proportion of patients who received anti-thymocyte globulin (ATG) induction was also less in the group with overseas kidney transplantation (58% vs. 22%, p<0.001). Overseas transplantation is associated with an increased risk for graft rejection. Our study suggests that overseas kidney transplantation is possibly driven by a lack of donors, especially cadaveric. Counseling patients about risks associated with overseas kidney transplantation and encouraging the public to register for organ donation after death may help curb out this practice.