Neutrophil trends and bone marrow findings in two patients with immune neutropenia treated with ruxolitinib. (A and D) Neutrophil counts for case 1 (A) and case 2 (D) over time, with shaded areas indicating the normal range (1.5–8.0 × 10⁹/liter) and annotated arrows marking ruxolitinib (RUX) dosing changes. (B and C) Case 2 bone marrow biopsy (B and C) shows slightly hypercellular bone marrow with trilineage hematopoiesis and a relative decrease in mature neutrophils. Panels show hematoxylin and eosin–stained sections at 50× (B) and 400× (C) magnification.