Pertussis is a common infectious disease affecting both children and adults. In young infants, it can cause severe respiratory illness associated with prolonged hospitalization and high mortality, particularly in cases complicated by severe leukocytosis and lymphocytosis, which increase the risk of pulmonary hypertension and multiorgan failure. Exchange transfusion remains the traditional first-line treatment for severe pertussis-associated hyperleukocytosis. However, in centers with appropriate resources and expertise, leukapheresis may be considered as an alternative therapeutic option. Leukapheresis enables selective reduction of circulating white blood cells, which are thought to play a central role in the pathophysiology of severe pertussis, while avoiding exposure to allogeneic blood products. It may also result in incidental platelet removal, potentially reducing blood viscosity and thrombotic risk in patients with concomitant thrombocytosis. Despite these potential advantages, leukapheresis is technically demanding and should be performed only in experienced centers with established protocols and appropriate expertise. Through the apheresis system we treated two patients who developed malignant pertussis with which successfully decreased their WBC counts by more than 50%. In the presence of limited guidance in the current literature regarding its prescription, usage, and safety specifically in pertussis, this report provides additional insights into the prescription and implementation of an effective leukocyte depletion.

Bruton tyrosine kinase inhibitors (BTKis) are standard therapy for chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL). The second-generation BTKi, acalabrutinib, has similar efficacy but a more favorable cardiovascular toxicity profile than the first-generation BTKi ibrutinib. This retrospective, observational, real-world study used electronic medical records from ONCare Alliance, a network of 32 US community oncology/hematology practices. Adults (N = 454) with treatment-naïve CLL/SLL who initiated acalabrutinib or ibrutinib monotherapy between January 2017 and December 2023 were included (n = 227 per group). Baseline characteristics were well balanced. The primary endpoint was time to new/worsening hypertension; the key secondary endpoint was time to treatment failure (TTF). After a median follow-up of 28 months, acalabrutinib had fewer discontinuations due to intolerability (19.4% vs 46.7%; p<.001), a significantly lower risk of new/worsening hypertension (HR 0.27; 95% CI, 0.14-0.55; p<.001), and prolonged TTF (HR 0.42; 95% CI, 0.31-0.56; p<.001) versus ibrutinib. Sensitivity analyses demonstrated stability in the findings.