What is the differential diagnosis for lymphocytosis (increased lymphocytes)?

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Differential Diagnosis for Increased Lymphocytes

  • Single Most Likely Diagnosis

    • Viral infections (e.g., mononucleosis, influenza): A common cause of increased lymphocytes, especially in the context of recent illness or exposure to infectious agents.
  • Other Likely Diagnoses

    • Chronic demyelinating polyneuropathy: An autoimmune disorder that can cause an increase in lymphocytes.
    • Chronic infections (e.g., tuberculosis, HIV): Long-standing infections can lead to a sustained increase in lymphocytes.
    • Autoimmune disorders (e.g., rheumatoid arthritis, lupus): Conditions characterized by an abnormal immune response, which can result in increased lymphocytes.
    • Lymphocytosis associated with stress or exercise: Transient increases in lymphocytes can occur in response to physical or emotional stress.
  • Do Not Miss Diagnoses

    • Lymphoma (e.g., Hodgkin lymphoma, non-Hodgkin lymphoma): A type of cancer that affects the immune system and can present with increased lymphocytes.
    • Leukemia (e.g., chronic lymphocytic leukemia): A cancer of the blood and bone marrow that can cause an increase in lymphocytes.
    • Severe combined immunodeficiency (SCID): A rare, life-threatening condition characterized by a defective immune system.
  • Rare Diagnoses

    • Castleman disease: A rare disorder characterized by an overgrowth of cells in the lymph nodes, which can cause increased lymphocytes.
    • Angioimmunoblastic T-cell lymphoma: A rare and aggressive type of lymphoma that can present with increased lymphocytes.
    • Pseudolymphoma: A rare condition characterized by an abnormal immune response, which can mimic lymphoma and cause increased lymphocytes.

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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