Effectiveness and safety of oral anticoagulants in patients with sickle cell disease and venous thromboembolism: a retrospective cohort study.

Patients with sickle cell disease (SCD) experience initial and recurrent venous thromboembolism (VTE) more commonly and at a younger age than the general population, and it confers a higher mortality for patients with SCD. However, limited evidence is available to guide anticoagulant use for VTE treatment in this population. The primary objective of this study is to characterize the effectiveness and safety of direct oral anticoagulants (DOAC) and warfarin for VTE treatment among patients with SCD. This single-center retrospective study includes adult patients with SCD who were diagnosed with VTE. Data was obtained from review of electronic health records for the 6 months after VTE diagnosis. Among the 22 patients treated initially with a DOAC, 6 (27%) developed recurrent VTE, none experienced major bleeding, and 3 (14%) experienced clinically relevant non-major bleeding (CRNMB). Similarly, of 15 patients initially treated with warfarin, 3 (20%) developed a recurrent VTE, 1 (7%) experienced major bleeding, and 2 (13%) experienced CRNMB. Twelve patients received more than one oral anticoagulant during the study period, most commonly due to a recurrent VTE, concern for non-adherence, or subtherapeutic INR. Overall, the incidence of VTE recurrence and bleeding events were similar between groups, but occurred at a higher rate than those found in major clinical trials of anticoagulant agents. Prescribers should continue to individualize therapeutic decision-making regarding oral anticoagulant therapy for VTE treatment for individuals with SCD based on patient-specific factors and anticipated ability to adhere to the drug regimen or required monitoring.

Multicenter COMPACT study of COMplications in patients with sickle cell disease and utilization of iron chelation therapy.

BACKGROUND: Over the past few decades, lifespans of sickle cell disease (SCD) patients have increased; hence, they encounter multiple complications. Early detection, appropriate comprehensive care, and treatment may prevent or delay onset of complications. OBJECTIVE: We collected longitudinal data on sickle cell disease (SCD) complication rates and associated resource utilization relative to blood transfusion patterns and iron chelation therapy (ICT) use in patients aged ≥16 years to address a gap in the literature. RESEARCH DESIGN AND METHODS: Medical records of 254 SCD patients ≥16 years were retrospectively reviewed at three US tertiary care centers. MAIN OUTCOME MEASURES: We classified patients into cohorts based on cumulative units of blood transfused and ICT history: <15 units, no ICT (Cohort 1 [C1]), ≥15 units, no ICT (Cohort 2 [C2]), and ≥15 units with ICT (Cohort 3 [C3]). We report SCD complication rates per patient per year; cohort comparisons use rate ratios (RRs). RESULTS: Cohorts had 69 (C1), 91 (C2), and 94 (C3) patients. Pain led to most hospitalizations (76%) and emergency department (ED) (82%) visits. Among transfused patients (C2+C3), those receiving ICT were less likely to experience SCD complications than those who did not (RR [95% CI] C2 vs. C3: 1.33 [1.25-1.42]). Similar trends (RR [95% CI]) were observed in ED visits and hospitalizations associated with SCD complications (C2 vs. C3, ED: 1.94 [1.70-2.21]; hospitalizations: 1.61 [1.45-1.78]), but not in outpatient visits. CONCLUSIONS: Although the most commonly reported SCD complication among all patients was pain, patients who received ICT were less likely to experience pain and other complications than those who did not. These results highlight the need for increased patient and provider education on the importance of comprehensive disease management.

Haemophilus influenzae type B in an immunocompetent, fully vaccinated ALL survivor.

A 7-year-old boy with a history of recurrent acute lymphoblastic leukemia (ALL), in remission, presented to primary care clinic after 2 days of progressive right hip pain with weight-bearing activities. He was otherwise asymptomatic at the time of presentation. Blood cultures revealed Gram-negative diplococci, which prompted an MRI that was significant for a hip joint effusion and femoral head bone marrow edema. The patient had no sick contacts and no significant past medical history other than ALL. The patient had been given all recommended childhood vaccinations. Arthrocentesis and needle biopsy of the femoral neck were not diagnostic for malignancy and revealed only mild hip joint inflammation, leading to a diagnosis of osteomyelitis. The organism in the original blood culture was identified as Haemophilus influenzae type b, ß-lactamase negative. Review of the patient's medical records showed a history of complete immunization to Haemophilus influenzae type b. An immunologic evaluation was made to determine if the patient retained immunity from his other vaccinations. Pathogen-specific antibody testing revealed detectable antibodies to polio but not measles, mumps, rubella, varicella-zoster virus, tetanus, diphtheria, pertussis, or hepatitis B. This loss of immunologic memory appears to be a rarely described side effect of ALL chemotherapy. There is currently no protocol to evaluate the immunologic memory of patients who underwent chemotherapy for ALL or to revaccinate them after their treatment. It is unclear whether the loss of immunologic memory is genuinely rare or is underdiagnosed because affected patients are protected by herd immunity.