Unexplained arterial thrombosis: approach to diagnosis and treatment.

Arterial thrombotic events in younger patients without a readily apparent etiology present significant diagnostic and management challenges. We present a structured approach to diagnosis with consideration of common causes, including atherosclerosis and embolism, as well as uncommon causes, including medications and substances, vascular and anatomic abnormalities, systemic disorders, and thrombophilias. We highlight areas of management that have evolved within the past 5 years, including the use of dual-pathway inhibition in atherosclerotic disease, antithrombotic therapy selection in embolic stroke of undetermined source and left ventricular thrombus, the role of closure of patent foramen ovale for secondary stroke prevention, and the thrombotic potential of coronavirus disease 2019 infection and vaccination. We conclude with a representative case to illustrate the application of the diagnostic framework and discuss the importance of consideration of bleeding risk and patient preference in determining the appropriate management plan.

Practical approach to monitoring and prevention of infectious complications associated with systemic corticosteroids, antimetabolites, cyclosporine, and cyclophosphamide in nonmalignant hematologic diseases.

Corticosteroids constitute a first-line therapy for adults and children suffering from nonmalignant immune-mediated hematologic diseases. However, high disease relapse rates during the tapering period or upon drug discontinuation result in long-term corticosteroid use that increases the risk of infection. This same concept applies to other immunosuppressive agents, such as antimetabolites, calcineurin inhibitors, and cyclophosphamide. Corticosteroids are associated with a length-of-treatment and dose-dependent risk for infection. Screening and antimicrobial prophylaxis against tuberculosis, hepatitis B, Strongyloides stercoralis, and Pneumocystis jirovecii pneumonia (PJP) might be indicated in patients who are scheduled to be on high-dose corticosteroids for >4 weeks (>30 mg of prednisone-equivalent dose [PEQ]) or in patients chronically treated (≥8 weeks of continuous or intermittent corticosteroid use) with moderate doses (≥15 to <30 mg PEQ). Antimetabolites (azathioprine, mycophenolate) increase the risk of progressive multifocal leukoencephalopathy (PML); however, other opportunistic infections and viral reactivation have also been reported. In case of new onset of neurological symptoms, PML needs to be considered, and an urgent neurology consultation should be obtained. Cyclophosphamide-induced myelosuppression can lead to serious infections related to neutropenia. PJP prophylaxis should be considered with combination therapy of cyclophosphamide and corticosteroids until a PEQ dose ≤ 5 mg/d is reached. Data on infectious risk when cyclosporine is used in patients with nonmalignant hematologic diseases are lacking. Discontinuation of any immunosuppressive agent during an episode of infection is recommended. In all patients, adherence to an age-based immunization schedule is appropriate.

Vascular thromboembolic events following COVID-19 hospital discharge: Incidence and risk factors.

BACKGROUND: Coronavirus disease 2019 (COVID-19) is associated with high rates of thromboembolic events in hospitalized patients. It remains to be determined if this risk persists following hospital discharge. METHODS: We conducted a retrospective cohort study of outpatients recently hospitalized for COVID-19 to determine the incidence of vascular thromboembolic events within 30 days of discharge. We investigated the risk factors associated with these events, including intensive care admission, age, and anticoagulation. RESULTS: Among 447 patients hospitalized for COVID-19, 2.0% experienced a vascular thromboembolic event within 30 days of discharge. No risk factor variable was significantly associated with an increased risk for these events. CONCLUSIONS: The incidence of vascular thromboembolic events following hospital discharge for COVID-19 is low. These findings suggest against the routine use of postdischarge thromboprophylaxis in patients with COVID-19.