COVID-19 and Sickle Cell Disease in the Province of Quebec, Canada: Outcomes after Two Years of the Pandemic.

BACKGROUND: Patients with sickle cell disease (SCD) are considered at higher risk of severe COVID-19 infection. However, morbidity and mortality rates are variable among countries. To date, there are no published reports that document outcomes of SCD patients with COVID-19 in Canada. METHODS: A web-based registry was implemented in June 2020 capturing outcomes of SCD patients with COVID-19 from March 2020 to April 2022 and comparing them to the general population of Quebec, Canada. RESULTS: After 24 months of the pandemic, 185 SCD patients with confirmed SARS-CoV-2 infection were included in the registry. Overall, the population was young (median age 12 years old) and had few comorbidities. No deaths were reported. Risk of hospitalization and admission to intensive care unit (ICU) because of COVID-19 was higher in patients with SCD than in the general population (relative risks (RR) 5.15 (95% confidence interval (95% CI) 3.84-6.91), p ˂ 0.001 and 4.56 (95% CI 2.09-9.93) p ˂ 0.001). A history of arterial hypertension or acute chest syndrome in the past 12 months was associated with a higher risk of severe disease (RR = 3.06 (95% CI 1.85-5.06) p = 0.008 and 2.27 (95% CI 1.35-3.83) p = 0.01). Hospitalized patients had lower hemoglobin F than non-hospitalized patients (12% vs. 17%, p = 0.02). For those who had access to vaccination at the time of infection, 25 out of 26 patients were adequately vaccinated and had mild disease. CONCLUSIONS: The SCD population is at higher risk of severe disease than the general population. However, we report favorable outcomes as no deaths occurred. Registries will continue to be critical to document the impact of novel COVID-19 specific therapy and vaccines for the SCD population.

Relative decrease in hemoglobin and outcomes in patients undergoing kidney transplantation surgery: A retrospective cohort study.

BACKGROUND: Recent surgical literature suggests that a relative decrease in hemoglobin (ΔHb) is predictive of adverse outcomes regardless of the absolute level. We aimed to examine the association between perioperative ΔHb and kidney transplantation (KT) outcomes. METHODS: This was a retrospective cohort study of transplant recipients, where ΔHb = [Hb0- Hb1Hb0]x 100 (Hb0 = hemoglobin pre-KT and Hb1 = lowest hemoglobin 24-h post-KT). The main outcome of interest was immediate graft function (IGF). RESULTS: Of the 899 eligible patients, 38% experienced IGF, and ΔHb was associated with 36% lower odds of IGF. Also, ΔHb was associated with higher all-cause graft failure and longer length of stay but not death-censored graft failure or mortality. ΔHb ≥30% was the threshold beyond which the odds of IGF were significantly lower even if Hb1 was ≥7 g/dL. CONCLUSION: ΔHb is associated with inferior outcomes independent of Hb1; whether it can be used to guide transfusion practices should be explored.

Thrombotic Microangiopathy in a Pregnant Woman With Kidney Transplantation: A Case Report.

BACKGROUND: The differential diagnosis of thrombotic microangiopathy (TMA) in pregnancy includes common conditions, such as preeclampsia. In women with kidney transplantation, additional causes of TMA must be considered. CASE: A 22-year-old primigravid woman with a transplanted kidney presented with fetal growth restriction, hypertension, acute kidney injury, and hemolysis at 28 weeks gestation. While her clinical presentation was initially consistent with preeclampsia, hemolysis persisted beyond 1 week postpartum. Diagnoses of TMA associated with tacrolimus and antibody-mediated rejection were considered. An elevated tacrolimus level likely contributed to her TMA and a decrease in dosage improved her clinical picture and laboratory markers. CONCLUSION: We report the case of a pregnant kidney transplant recipient with TMA. A multidisciplinary approach is required to optimize the maternal health outcomes in this complex population.

An innovative short-stay health care model for treatment of uncomplicated vaso-occlusive crisis in adult sickle cell disease patients in Canada to reduce emergency department utilization.

OBJECTIVES: Patients with sickle cell disease (SCD) with vaso-occlusive crises (VOC) often visit the emergency department (ED) for management of painful episodes. The primary objective of this pilot study was to evaluate the acceptability of a short-stay model for treatment of VOC in SCD outside of the ED in Toronto, Canada. Secondary objectives were to assess patient satisfaction of this model, barriers to its use and comparison of clinical outcomes to a historical control. METHODS: Adult SCD patients with symptoms of an uncomplicated VOC between October 2014 to July 2016 were managed according to best practice recommendations in a short-stay unit as an alternative to the local emergency room. Primary outcome of time to first analgesia, and secondary outcome of discharge rate were compared to a historical control at a local ED from 2009-2012. Satisfaction and barriers to use of the ambulatory care delivery model were assessed by patient survey. RESULTS: Twenty-one visits were recorded at the short-stay unit during the study period. Average time to first opiate dose was 23.5 minutes in the short-stay unit compared to 100.3 minutes in the ED (p4/5 on Likert scale) except for geographic accessibility (85% response rate, n=18). CONCLUSION: This study demonstrated high patient satisfaction and acceptability of a short-stay model for treatment of uncomplicated VOC in adult SCD patients in Toronto, the first of its kind in Canada.

Safety and feasibility of red cell exchange for sickle cell disease across Canada.

We outline a case whereby RBCX was successfully provided over disparate geographical areas and time zones in Canada and overcame the logistical challenges of coordinating care across four different health care systems with the application of modern telecommunication technologies. We present this case as a model for other SCD providers and patients.

In vivo profiling of focal cortical dysplasia on high-resolution MRI with computational models.

PURPOSE: On MRI, focal cortical dysplasia (FCD) is characterized by a combination of increased cortical thickness, hyperintense signal within the dysplastic lesion, and blurred transition between gray and white matter (GM-WM). The visual identification of these abnormal characteristics may be difficult, and it is unclear to what degree these features occur among different FCD lesions. Our purpose was to investigate the pattern of occurrence of abnormal MRI characteristics in FCD by using a set of computational models and to generate quantitative lesion profiling. METHODS: A set of voxel-wise operators was applied to high-resolution 3D T1-weighted MRI in 23 patients with histologically proven FCD and 39 healthy controls, creating maps of GM thickness, maps of relative intensity highlighting areas with hyperintense signal, and maps of gradient magnitude modeling the GM-WM transition. All FCD lesions were segmented manually on the T1-weighted MRI. RESULTS: FCD volumes ranged from 734 mm3 to 80,726 mm3 (mean, 8,629 mm3 +/- 16,238). The manually segmented FCD lesions were used to estimate features in the lesional area and to determine possible local variations of each feature by means of a histogram. In 78% of the patients, FCD lesions were characterized by simultaneous GM thickening, hyperintense signal, and blurring of the GM-WM transition. Moreover, in all patients, the FCD lesion had at least two of these three characteristics. CONCLUSIONS: The three features occurred regardless of the lesion volume, and they characterized not only large FCD lesions, but also subtle ones that had been overlooked by conventional radiologic inspection before surgery.