This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Hematology, Subject name: Pediatrics
Kostmann&;s syndrome-treatment is 
Select and explain. 
A. Anti-thymocyte globulin + cyclosporin, B. Anti-thymocyte globuline + cyclosporine + GM-CSF, C. G-CSF, D. GM-CSF
C: G-CSF
Answer: C: G-CSF 
Explanation: kostmann syndrome characterized by hereditary neutropenia and treatment of choice is administration of granulocyte colony stimulating factor. Severe Congenital Neutropenia (Kostmann&;s Syndrome) * Clinical manifestations: Chronic severe neutropenia present at bih Accumulation of granulocytic precursors in the bone marrow Recurrent infections * Treatment with G-CSF -- Reduces infections and improves survival * Marked propensity to develop acute myeloid leukemia or myelodysplasia Reference: GHAI Essential pediatrics, 8th edition