Central Retinal Vein Occlusion After Discontinuation of Rivaroxaban Therapy in a Young Patient with COVID-19 Pulmonary Embolism: A Case Report.

BACKGROUND We present the report of the first case, to the best of our knowledge, of central retinal vein occlusion (CRVO) that occurred 3 days after anticoagulation discontinuation in a patient with a history of pulmonary embolism in the course of COVID-19. CASE REPORT A previously healthy 38-year-old man was hospitalized in April 2021 with severe COVID-19 pneumonia, complicated by segmental and subsegmental pulmonary embolism. The patient was treated with a concurrent combination of remdesivir, dexamethasone, therapeutic enoxaparin, ceftriaxone, passive oxygen therapy, and convalescent plasma therapy, which led to pulmonary improvement. The treatment with therapeutic enoxaparin (80 mg/0.8 mL twice a day) was continued for 1 month after discharge, followed by 15 mg of rivaroxaban twice a day for 3 weeks and 20 mg of rivaroxaban once a day for 11 weeks. Within 3 days after rivaroxaban discontinuation, the patient experienced a decrease in visual acuity in his right eye, to the level of 5/25. Nonischemic CRVO with cystoid macular edema was diagnosed and an intravitreal injection of ranibizumab was performed. Common identifiable factors contributing to CRVO were excluded, and the treatment with prophylactic enoxaparin was initiated. Two weeks later, macular edema decreased significantly and visual acuity improved to 20/20. The treatment with enoxaparin was discontinued. CONCLUSIONS Rebound hypercoagulability after discontinuation of rivaroxaban therapy can manifest as CRVO in a young patient with a history of COVID-19 pulmonary embolism. It was successfully treated with an intravitreal injection of ranibizumab.

Potential of redox therapies in neurodegenerative disorders.

Recently significant advances have been made to understand the pathophysiological mechanisms of neurodegenerative disorders to provide real therapeutic benefits. There is evidence that persistent inflammation and oxidative stress are the crucial factors of ongoing cell damage in neurodegenerative complex etiology. The variety of reactive oxygen and nitrogen species are the cause of both axonal and neuronal destruction, which is pathological hallmark of neurodegeneration. Therefore, the reduction of oxidative stress is currently one of the main neuroprotective strategies. The World Health Organization (WHO) estimates that, by 2040, neurodegenerative diseases will be the main cause of death in industrialized countries ahead of the cancers. The redox therapeutic approch can target: degnerative component, inflammatory/autoimmune component and neurodegenerative component. Redox therapy should not be applied uniformly, and must be develop to target specific mechanisms. This review focus on the main antitoxidative therapies that are used in many countries as a supplements or even as a standart treatment. Aditionally, clinical synmptoms of most common neurodegenerative disordes and centralnervous system structures involved in oxidative/nitrosative stress are showed.