Neupogen (Filgrastim) Induced Acute Hematuria/Proteinuria with 3 Days of Use in a 7-Year-old Boy Diagnosed as Aplastic Anemia

Filgrastim is a recombinant human Granulocyte Colony-stimulating Factor (G-CSF) approved by the US Food and Drug Administration [1]. It is used to treat patients with neutropenia caused by chemotherapy [2–5], human immunodeficiency virus infection [6], bone marrow transplant [7–9], or in cases of congenital [2,7], cyclic [2,10], or idiopathic neutropenias [2,11]. It is a hematopoietic growth factor that influences leukopoiesis [12–14], and affects the proliferation and differentiation of neutrophils within the bone marrow [15,16] and possibly other sites (e.g., spleen) [17,18]. It binds directly to G-CSF receptors on neutrophil progenitor target cell surfaces [19,20] and stimulates neutrophil proliferation, thereby increasing neutrophil counts and activity [21,22].