Toxic granules are mainly composed of peroxidase and acid hydrolase enzymes,[3] and are similar in composition to the primary granules found in immature granulocytic cells like promyelocytes.[4][5] Although normal, mature neutrophils do contain some primary granules, the granules are difficult to identify by light microscopy because they lose their dark blue colour as the cells mature. Toxic granulation thus represents abnormal maturation of neutrophils.[6]
Similar conditions
Patients with the inherited condition Alder-Reilly anomaly exhibit very large, darkly staining granules in their neutrophils, which can be confused with toxic granulation.[2][7]