Blood/Blood Cells and Cellular Components ›› Monocytes ›› Abnormal
Increased Mature Monocytes
›Microscopic Features:
- 3-4x larger than a mature RBC
- Lower nuclear to cytoplasmic ratio because of increased cytoplasm
- Kidney shaped Indented Nucleus with mature chromatin (clumped)
- Nucleoli is absent
- Cytoplasm is abundant, gray to pale blue and lacks granules
- vacuoles are commonly noted in cytoplasm
›Normal % blood-PB, marrow-BM, lymphoid tissue-LN:
- PB: Monocytes are the 3rd most common WBC in the blood (after neutrophils and lymphocytes)
- BM: Scattered monocytes can be seen in the bone marrow (some as histiocytes/macrophages)
- LN: Scattered monocytes can be seen in the bone marrow (some as histiocytes/macrophages)
›May Resemble:
›Differential Diagnoses:
If increased in blood or increased numbers in bone marrow:
Chronic Myelomonocytic Leukemia
Chronic neutropeniacollagen
Autoimmune (sometimes)
Chronic infections (e.g. CMV, tuberculosis, etc.)
Chronic Myelomonocytic Leukemia
Chronic neutropeniacollagen
Autoimmune (sometimes)
Chronic infections (e.g. CMV, tuberculosis, etc.)
›Classic Immunophenotype:
- N/A
›Cartoon Image:
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›Misc:
Increased monocytes can be associated with many processes including but not limited to infectious etiologies, etc.