Systemic thrombolysis for acute central retinal artery occlusion in sickle cell disease: Case report.

INTRODUCTION: In sickle cell disease (SCD), blood oxygen content is decreased due to anemia and the Hb-SS phenotype, in particular leads to an increased blood viscosity, which limits tissue oxygen delivery. Nonetheless, vasculopathy, correlating with daytime oxygen saturation,1 thrombophilia and hyper coagulability are all underappreciated etiologies of stroke in SCD.2 As a result, there is less known about the role of systemic thrombolysis for the management of acute stroke in SCD. Given the lack of studies and cases reviewed in literature, we describe a patient with SCD found to have an acute stroke treated with both intravenous (IV) alteplase and exchange transfusion. RESULTS & DISCUSSION: We describe a 42-year-old African- American man with SCD (HbSS) who presented with an acute central retinal artery occlusion (CRAO) within an hour of onset and subsequently received IV thrombolysis with alteplase. His labs were significant for HbS 91%. He had no central vascular access to undergo emergent red blood cell (RBC) exchange so interventional radiology was consulted to minimize his bleeding risk after receiving tissue plasminogen activator (tPA). A right internal jugular catheter was placed with fluoro-guidance, resulting in minimal blood loss. After two sessions of RBC exchange, his HbS decreased to 26%. He reported an improvement of vision in his left eye the day following acute management and followed up with Hematology for secondary stroke prevention. IMPLICATIONS: In reviewing this case, we recommend that current clinical trials for management of acute stroke including an acute CRAO carefully consider including patients with sickle cell disease to receive simultaneous IV thrombolysis and RBC exchange. The benefits outweigh the risk of a permanent disabling deficit with significant functional impairment. And while considering care plans tailored to the projected needs of acute care management for this patient population, we also recommend implementing healthcare models that improve access to preventative care in settings where the majority of children and adults with SCD live.

Tolerability of memantine monotherapy versus adding memantine as combination therapy.

INTRODUCTION: Prior studies have focused on the clinical efficacy of combination therapy, donepezil and memantine, for patient's diagnosed with Alzheimer's disease. As a result, it has become increasingly routine for providers to prescribe both medications for all-cause neurodegenerative disorders in variable stages of disease. However, the potential adverse drug reactions while described as mild can have serious sequelae in older adults who are already managing the side effects of polypharmacy. This study looks to explore the tolerability of switching cholinesterase inhibitors to memantine monotherapy versus adding memantine as combination therapy for all-cause neurodegenerative disorders. MATERIALS & METHODS: The study is an IRB approved retrospective chart review that includes 175 patients diagnosed with neurocognitive disorders (ICD 10 F00-F03.91 and ICD10 G30-G31.84). Only side effects reported to and recorded by a neurocognitive subspecialist at Jefferson's Memory Disorder Center from 2016 to 2019 were included. RESULTS & DISCUSSION: The odds of a patient reporting side effects on combination therapy in comparison with those patients on memantine monotherapy reporting side effects were significantly greater (OR = 4.33, CI 95% (1.62, 11.52), p = 0.003). In our patient sample, more than 80% of the patients reporting side effects qualified as polypharmacy or excessive polypharmacy (Table 2). As a result, variable polypharmacy (p = 0.047) was statistically significant in the in a binary logistic regression model for predicting outcomes for patients on combination therapy (Table 3). Therefore, as a patient progresses to moderate-severe stages of disease, we recommend switching CI monotherapy to memantine monotherapy as opposed to adding memantine as combination therapy for those patients on more than 10 other medications to increase tolerability. Given the limitations of a smaller sample size, variables such as severity of disease, renal and liver impairment as well as medication dosing were not significant predictors (Table 3) for those reporting side effects on combination therapy.