Investigations showed anemia (Hb 9.6 g/dL), marked leukocytosis with neutrophilic predominance (WBC count 31.4 × 109 cells/L), thrombocytosis (platelet count 800 × 109/L), CRP 345.3 mg/L, marked hyperammonemia of >600 (16–52) μmol/L, hypogammaglobulinemia (immunoglobulin G, 4.3 g/L; immunoglobulin A, <0.4 g/L; immunoglobulin M, <0.3 g/L), with normal renal and liver function tests. Here, GSTM1 is linked to Thrombocytosis.