Page 356 - Clinical Hematology_ Theory _ Procedures ( PDFDrive )

340 PART 5 ■ Nonmalignant Leukocyte Disorders

TABLE 18.2 Comparative Morphological Characteristics of Granulocyte Abnormalities (continued)

Classi cation Name of Abnormality Major Characteristic Associated Condition

Döhle bodies Single or multiple, light-blue–staining Represent aggregates of rough

inclusions on Wright-stained blood endoplasmic reticulum (RNA) and

smears may be associated with a variety

of conditions such as viral infec-

tions, burns, or certain drugs. Döhle

body–like inclusions may be seen in

May-Hegglin anomaly.

Ehrlichia Ehrlichia are small, gram-negative

bacteria that primarily invade leu-

kocytes. Ehrlichia typically appear

as minute, round bacteria (cocci),

ranging from 1 to 3 µm in diameter.

In the leukocytes, Ehrlichia divide to

form vacuole-bound colonies known

as morulae, the Latin word for mul-

berry, referring to the mulberry-like

clustering of the dividing organisms.

The formation of morulae is a de n-

ing characteristic of this group of

bacterial pathogens.

Vacuoles Circular membrane-enclosed Number and/or size of vacuoles

structures in the cytoplasm increases as a cell ages. The con-

tents of vacuoles consist of water and

soluble waste products of the cell.

Inherited May-Hegglin anomaly Presence of Döhle body–like inclu- 50% of patients do not have symp-

Functional sions in neutrophils, eosinophils, toms; others have manifested abnor-
Abnormalities and monocytes. Abnormally large mal bleeding tendencies. The cause

and poorly granulated platelets and of the hemostatic defect is unclear,
thrombocytopenia (a decreased num- but it is proportionate to the degree of

ber of platelets) frequently coexist in thrombocytopenia.
this condition.

Chédiak-Higashi syndrome Characterized by very large granules. Neutrophils display impaired chemo-

These gigantic, peroxidase-positive taxis and delayed killing of ingested

deposits represent abnormal lyso- bacteria. Patients with this disorder

somal development in neutrophils suffer from frequent infections, which

and other leukocytes, such as suggests that neutrophils with this

monocytes and lymphocytes defect are not ef cient bactericidal

cells.

Alder-Reilly inclusions Purple-red particles are precipitated Alder-Reilly granules are most com-

mucopolysaccharides seen primar- monly seen in patients with Hurler’s,

ily in neutrophils, eosinophils, and Hunter’s, and Maroteaux-Lamy types

basophils. of genetic mucopolysaccharidosis.

Chronic granulomatous

disease

Myeloperoxidase

de ciency

Leukocyte adhesion
de ciency