Granulocyte Number

Question 1

1. Identify the basic morphologic features of neutrophils, eosinophils, basophils, monocytes, and macrophages and explain their production, distribution, and turnover.

Answer 1

All produced by CFU-GM cells in the BM.

Neutrophils = segmented nuclei
Distribution: marrow –> ‘storage pool’ –> infection –> circulate ~6h –> tissues, die after 7-24h later

Monocytes and macrophages are kind of amorphic and tend to show vacuoles.
Developed in marrow for 7 days –> blood for 3-5 days –> tissues (days to months)

Eosinophils (bi-lobed) stain red or orange
Basophils stain blue due to their acidic granules
mature –> blood –> tissues –> survive for weeks.

Question 2

Define neutropenia and describe the clinical consequences of neutropenia.

Answer 2

Decrease in the absolute neutrophil count (bands and segs) below accepted norms (varies with age & ethnicity, see below)

dec delivery of neutrophils to infected tissues —> shift the balance in favor of the microbes.

Question 3

3. Diagram the major causes and differentiate the major acquired or congenital/genetic disorders of neutropenia.

Answer 3

Marked decrease bone marrow reserve

• Primary disorders: Kostmann syndrome, Shwachman-Diamond syndrome, cyclic neutropenia
• Secondary: Chemotherapy, drug induced (non-immune), nutritional, viral infection
• Part of a complex phenotype, e.g., Glycogenosis Ib, Cartilage-hair hypoplasia
• Other: e.g., idiopathic

Normal marrow reserve

• Immune: Chronic benign neutropenia of childhood, autoimmune, alloimmune, drug induced, infection
• Non-immune: Infection, hypersplenism, excessive margination

Question 4

Discuss major treatment strategies including growth factors for treating neutropenia.

Answer 4

Broad spectrum ABX
G-CSF
IVIG

Question 5

Define leukocytosis and provide reasons for a high white blood cell count. Describe the term “left shift” and what it indicates.

Answer 5

An increase in total WBC beyond norms

• infection
• inflammation
• some other stress
• malignancy (leukemia)

“Left shift” is a term which describes changes in a normal white blood cell differential characterized by an increase in neutrophils (segs and bands).

Question 6

Eosinophilia

Answer 6

> 350/ul

• allergies/allergic disorders (asthma, atopic dermatitis, hay fever, hives, etc.),
• parasitic infections
• drug reactions (allergic).

Rarer causes include pemphigus, tumors or malignancies, and other infections like chronic active hepatitis. Hypereosinophilic syndromes and eosinophilic leukemia are rare.

Question 7

Basophila

Answer 7

Seen primarily in drug or food hypersensitivity or urticaria.

• Infection
• Inflammation (rheumatoid arthritis, ulcerative colitis, influenza, chickenpox, smallpox, tuberculosis)
• Myeloproliferative diseases (CML, myeloid metaplasia).

Question 8

Monocytosis

Answer 8

Newborns: >1,000/μl Else: >500/μl

• hematologic (pre) malignancies (AML, pre-leukemia states, lymphoma, Hodgkin’s disease)
• Collagen vascular diseases (SLE, RA),
• Granulomatous diseases (sarcoid, ulcerative colitis, Crohn’s disease),
• Infections (subacute bacterial endocarditis, syphilis, tuberculosis, protozoal rickettsial, and Pertussis infections),
• Carcinoma