Hydroxyurea and zileuton differentially modulate cell proliferation and interleukin-2 secretion by murine spleen cells: Possible implication on the immune function and risk of pain crisis in patients with sickle cell disease

Background: Hydroxyurea (HU) reduces major complications associated with sickle cell disease in part because of the induction of fetal hemoglobin. However, because of its antiproliferative property, its long-term use may impair immunity. Zileuton, a derivative of HU, also induces fetal hemoglobin and has antiinflammatory properties, a feature that can reduce the risk of sickling. Our goal was to investigate the capacity of both drugs to modulate the secretion of interleukin-2 (IL-2), a regulatory cytokine for immune responses. Methods: Spleen cells obtained from 11 4-month-old C57BL/6 female mice were incubated without and with 10 µ/mL HU or zileuton, 2.5 µ/mL concanavalin A (ConA), 20 µ/mL phytohemagglutinin (PHA), and 50 ng/mL anti-CD3 antibody for 12-48 h. IL-2 was measured in the supernatant by enzyme-linked immunosorbent assay and cell proliferation byH-thymidine uptake. Results: While HU reduced lymphocyte proliferation in response to mitogens (

Fever and Leg Pain: Consider ALL the Diagnoses

Background: Acute lymphoblastic leukemia (ALL) is the most common childhood cancer diagnosed in the United States. The disease causes a decrease in hematopoiesis, so children often present with symptoms related to anemia, thrombocytopenia, and leukopenia. Symptoms for this malignancy may have significant overlap with other conditions such as osteomyelitis.Case Report: A 2-year-old male with no significant medical history presented with lower extremity pain and fever. Initial investigations, including imaging and complete blood count, led physicians to diagnose bilateral osteomyelitis. The patient was prescribed a course of antibiotics; however, his symptoms returned. Eventually, a bone marrow aspiration showed CD99 membrane-positive small round blue cell tumors. The patient was diagnosed with ALL. He was successfully treated with chemotherapy and is now in remission.Conclusion: This case demonstrates the importance of a broad differential diagnosis for a child presenting with leg pain and fever