Assessing the Performance of Extended Half-Life Coagulation Factor VIII, FC Fusion Protein by Using Chromogenic and One-Stage Assays in Saudi Hemophilia A Patients.

BACKGROUND: The one-stage assay is the most common method to measure factor VIII activity (FVIII : C) in hemophilia A patients. The chromogenic assay is another two-stage test involving purified coagulation factors followed by factor Xa-specific chromogenic substrate. AIM: This study aimed to assess the discrepancy and correlation between the chromogenic and one-stage assays in measuring FVIII : C levels in hemophilia patients receiving Extended Half-Life Elocta® as a recombinant extended half-life coagulation factor. METHODS: We performed a study comparing the measurements of FVIII : C levels by the chromogenic versus the one-stage assays at different drug levels. Data of FVIII : C levels, dosage, and the time interval from administration to measurement were retrieved from the hospital records. The correlation, mean differences, and discrepancy between the two assays were calculated. The linear regression analysis was used to predict the time interval till reaching 1% FVIII : C. RESULTS: Fourteen patients with 56 samples were included in the study. Of them, 13 patients were receiving Elocta® as a prophylactic, while one was receiving Elocta® on demand. One-third of these samples showed a discrepancy between the chromogenic and one-stage assays. The two assays were well correlated. Mean differences were significant at the individual and the time interval level. The time since the last Elocta® injection could significantly predict FVIII : C levels (ß = 0.366, P < 0.001). CONCLUSION: Our findings suggested a significant difference between both methods; the FVIII : C levels measured by the one-stage assay were less than those estimated by the chromogenic assay. However, the measurements of FVIII levels by the two assays were well correlated but discrepant in one-third of the samples. The levels of FVIII : C reach 1% after 5.4 days since the last Elocta® administration.

Characteristics and Outcomes of Younger Adults with Embolic Stroke of Undetermined Source (ESUS): A Retrospective Study.

INTRODUCTION: Embolic stroke of undetermined source (ESUS) in younger adults may have different risk factors compared with ESUS in elderly, and the approach to ESUS in young adults may require new therapies. We aimed to investigate the characteristics and outcomes in younger adults with ESUS at a single centre in Saudi Arabia. PATIENTS AND METHODS: A retrospective study was conducted using the medical records of younger adults with ESUS according to the criteria of the Cryptogenic Stroke/ESUS International Working Group. Younger adults (aged ≤50 years) with ESUS were compared with older patients, on admission and discharge from hospital, using the modified Rankin scale (mRS) and the National Institute of Health Stroke Scale (NIHSS). RESULTS: Among 147 patients with ESUS, 39 (26.5%) were younger adults. Younger adults compared with older adults with ESUS had fewer vascular risk factors, including lower rates of hypertension (43.6% vs. 70.3%; P = 0.004), diabetes (35.9% vs. 57.4%; P = 0.03), and dyslipidaemia (12.8% vs. 28.7%; P = 0.05). There was no significant difference in poor outcome at discharge (defined as mRS > 2), which was observed in 17.9% of younger adults and 28.7% of older adults. Further, there were no significant differences in stroke severity at discharge (NIHSS score ≤5) or median length of stay. DISCUSSION: Although the outcomes of ESUS do not differ between younger and older patients, younger patients have fewer identified risk factors. CONCLUSION: This study showed that 26.5% of patients with ESUS were aged ≤50 years. Although younger adults with ESUS had fewer risk factors, there were no significant differences in neurologic disability or mortality at discharge, stroke severity, or median length of stay.

Embolic Stroke of Undetermined Source in Saudi Arabia: Prevalence, Patient Characteristics, and Outcomes.

BACKGROUND: Embolic stroke of undetermined source (ESUS) is a newly introduced clinical construct to better characterize cryptogenic stroke. It is associated with considerable morbidity and mortality and a high recurrence rate. It has not previously been investigated in Saudi stroke patients. We aimed to conduct a descriptive analysis of ESUS in Saudi Arabia, including its frequency among patients with acute stroke, characteristics, and outcomes. METHODS: We reviewed all ischemic stroke patients admitted to the stroke unit at King Abdulaziz Medical City-Riyadh, Saudi Arabia, from February 2016 to July 2018. We applied the criteria proposed by the Cryptogenic Stroke/ESUS International Working Group, which defines ESUS as a radiologically confirmed nonlacunar brain infarct without (a) extracranial or intracranial atherosclerosis causing ≥50% stenosis in arteries supplying the ischemic area, (b) a major-risk cardioembolic source, (c) any other specific cause of stroke. We compared ESUS patients with the other stroke patients. Study was approved by local institutional review board. RESULTS: Of the 736 patients admitted with ischemic stroke, 147 (20%) had ESUS. Patients with ESUS had fewer vascular risk factors compared to patients without ESUS. Nearly third were either dead or dependent at discharge. There were no significant differences between ESUS and other types of ischemic strokes in mortality rate and independence at discharge. CONCLUSION: ESUS is common in Saudi stroke patients. Despite of the lack of definite etiology, it is associated with considerable morbidity and mortality.

Predictors of poor outcome in embolic stroke of undetermined source.

OBJECTIVE: To identify the clinical predictors of death or disability at discharge. METHODS: We retrospectively reviewed all ischemic stroke patients admitted to the stroke unit of King Abdulaziz Medical City, Riyadh, Saudi Arabia, from February 2016 - July 2018. We applied the Cryptogenic Stroke/ESUS International Working Group Embolic stroke of undetermined source (ESUS) criteria. We compared patients with poor outcomes (death or modified Rankin Scale [mRS] score more than 2 ) to those with favorable outcomes. Multivariate logistic regression was used to identify predictors of poor outcome. The regression model included age more than 60 years, gender, body mass index more than 25 kg/meter square, smoking history, comorbidities, previous ischemic/transient ischemic attack, pre-stroke mRS score more than 1, National Institutes of Health Stroke Scale (NIHSS) score at admission more than 5, pre-stroke antiplatelet use, and thrombolysis treatment. RESULTS: Out of 147 patients who met the ESUS criteria, 28.8% had poor outcomes. Predictors of poor outcome were NIHSS score more than 5 (odds ratio [OR] 11.1, 95% confidence interval [CI] 4.4-28.2), pre-stroke mRS score more than 1 (OR 3.7, 95% CI 1.14-11.59), and age more than 60 years (OR 2.4, 95% CI 1.14-5.22). CONCLUSION: A significant proportion of ESUS patients were dead or disabled at discharge. Poor outcome was more in older patients with pre-stroke functional disability and moderate to severe stroke.