Differential Diagnosis for WBC Differential
Single Most Likely Diagnosis
- Viral infection: A viral infection is often the most common cause of an abnormal WBC differential, with a typical presentation of lymphocytosis (increased lymphocytes) and sometimes a left shift (increased immature white blood cells).
Other Likely Diagnoses
- Bacterial infection: Bacterial infections can cause an increase in neutrophils (neutrophilia) and a left shift, indicating an acute inflammatory response.
- Allergic reaction: Allergic reactions can cause an increase in eosinophils (eosinophilia), which can be seen in conditions such as asthma or atopic dermatitis.
- Chronic inflammation: Chronic inflammatory conditions, such as rheumatoid arthritis or inflammatory bowel disease, can cause a persistent increase in WBCs, often with a left shift.
Do Not Miss Diagnoses
- Leukemia: Leukemia, such as acute lymphoblastic leukemia (ALL) or acute myeloid leukemia (AML), can cause an abnormal WBC differential, with an increase in blast cells (immature white blood cells).
- Sepsis: Sepsis, a life-threatening condition caused by a severe infection, can cause a significant increase in WBCs, often with a left shift and a decrease in platelets.
- Aplastic anemia: Aplastic anemia, a condition where the bone marrow fails to produce enough blood cells, can cause a decrease in WBCs, red blood cells, and platelets.
Rare Diagnoses
- Myeloproliferative neoplasm: Myeloproliferative neoplasms, such as polycythemia vera or essential thrombocytosis, can cause an increase in WBCs, red blood cells, and platelets.
- Lymphoma: Lymphoma, a type of cancer that affects the immune system, can cause an abnormal WBC differential, with an increase in lymphocytes.
- Parasitic infection: Parasitic infections, such as malaria or toxoplasmosis, can cause an increase in WBCs, often with a left shift and a decrease in platelets.