II. Definition: Neutropenia (Neutrophil Count < 1500/mm3)
- Agranulocytosis (severe Neutropenia)
- Complete absence of Neutrophils
- Neutropenia: Based on Absolute Neutrophil Count (ANC)
- Mild Neutropenia: ANC 1000 to 1500 Neutrophils/mm3
- Moderate Neutropenia: ANC 500 to 1000 Neutrophils/mm3
- Severe Neutropenia: ANC <500 Neutrophils/mm3
III. Precautions
- See Neutropenic Fever
- Avoid Rectal Exam in Neutropenia (theoretic risk of bacteremia)
IV. Causes
V. Differential Diagnosis: Pseudoneutropenia (automated)
- Blood examined after long delay after phlebotomy
- Margination (see Neutropenia Causes)
- Neutrophil clumping
VI. Signs: Recurrent infection
-
General
- Typical inflammation signs less commonly seen
- Swelling and heat less often seen with Neutropenia
- Organisms
- Staphylococcus aureus (skin)
- Gram Negative (Gastrointestinal, Genitourinary)
- Early severe Neutropenia
- Oropharyngeal infections
- Skin Infections or delayed Wound Healing
- Persistent severe Neutropenia
- Pulmonary infection
- Gastrointestinal infection
- Sepsis
VII. Labs
VIII. Evaluation: Bone Marrow Biopsy
- Indications
- Indicated in most Neutropenia cases
- Not required in mild Drug-Induced Neutropenia
- Increased Granulocytes in Bone Marrow
- Suggests increased destruction (e.g. immune)
- Decreased Granulocytes in Bone Marrow
- Increased cells seen in marrow
- Suggests marrow infiltration (e.g. Leukemia)
- Decreased cells seen in marrow
- Suggests marrow injury (e.g. medications)
- Increased cells seen in marrow
IX. Complications
- Severe Neutropenia predisposes to serious infection