Until the last follow-up, he had a stable disease with glucocorticoid treatment (0.2 mg/kg/day), characterized by moderately severe anemia (Hb 8.7–9.4 g/dL, reference 11.5–15.5 g/dL) with normal reticulocyte counts (70–100 × 109/L), a short stature but a normal growth velocity (at −2.5 SD) and no physical complaints. Here, GSTM1 is linked to anemia.