Identification of cell abnormalities--such as the large azurophilic granules
in toxic granulation, asynchronous maturation, micromegakaryocyte identification or quantitating variant lymphs--still requires a skilled human eye.
Electron microscopic studies suggest that these granules are formed by the fusion of azurophilic granules
The t(8; 21) subtype is characterized by large blasts with abundant basophilic cytoplasm, with perinuclear clearing or hofs, and numerous azurophilic granules.
The myeloid blasts in t(8; 21) AML are large, with abundant basophilic cytoplasm, with perinuclear hofs, occasional to numerous azurophilic granules, and blunted Auer rods.
1,2) The appearance of TG is the result of an increase in acid mucosubstance in azurophilic granules
, which stains more prominently than under normal circumstances.
Activity of tissue MPO, an enzyme that is found predominantly in the azurophilic granules
of polymorphonuclear leukocytes, correlates with the number of polymorphonuclear neutrophils determined histochemically in the inflamed tissues; it is therefore used as an indication of tissue neutrophil accumulation.
It has been also observed that increased myeloperoxidase which is present in azurophilic granules
of polymorphonuclear neutrophils, activity in periodontitis as compared to controls .
4, when viewed at a higher magnification, shows part of a polysomatic nucleus (PN) and several large globules slightly under-focused to show the superficial caps of densely azurophilic granules
in the optical plane above the spheres.
MPO, which is abundant in azurophilic granules
of neutrophils and in the lysosomes of monocytes, plays a key role in amplifying the toxicity of hydrogen peroxide generated by the respiratory burst (1), (2).
The blasts in the peripheral blood varied in appearance from small cells showing lymphoid features with a high nucleus-cytoplasmic ratio, sparse cytoplasm, dense nuclear chromatin, and inconspicuous nucleoli to larger forms with a lower nucleus-cytoplasmic ratio, a moderate amount of basophilic cytoplasm, few fine perinuclear azurophilic granules
, occasional cytoplasmic blebs or buds, dispersed nuclear chromatin, and distinct nucleoli.
Blasts with coarse azurophilic granules are seen in granular ALL and myeloid leukemia with basophilic differentiation, i.
In the two cases described here, coarse azurophilic granules were present in the blasts, both in peripheral blood smear and bone marrow, which were negative for myeloperoxidase and positive for TB.