I. Characteristics

  1. Function: Primary source of viral defense and Antibody
    1. Lymphocyte Sub-Classes
      1. B-Lymphocytes
        1. Differentiate into plasma cells
        2. Plasma cells release specific antibodies
      2. T-Lymphocytes
        1. Response to viral infection, cancer, foreign cell
      3. Natural Killer Cells (NK Cells)
        1. Attack cancer cells and cells infected with virus
  2. Morphology on Blood Smear
    1. Mononuclear Leukocytes (same class as Monocytes)
    2. Small cells with minimal cytoplasm

II. Interpretation: Normal

  1. Percentage Lymphocytes: 15-40% of White Blood Cells
  2. Total Lymphocytes: 800-2600/mm?
  3. Total T Lymphocytes: 800-2200/mm?
    1. T helper Cells: >400/mm?
    2. T suppressor Cells: 250-750/mm?
    3. Helper Cell to Suppressor Cell ratio: >0.9
    4. CD2 Percentage of Lymphocytes: 65-85%
    5. CD4 Percentage of Lymphocytes: 45-75%

III. Interpretation: Increased (Lymphocytosis)

  1. Increased Absolute Lymphocyte Count (>4500/mm3)
    1. Non-activated Lymphocytes
      1. Influenza
      2. Pertussis
      3. Tuberculosis
      4. Mumps
      5. Varicella
      6. Herpes Simplex Virus
      7. Rubeola
      8. Brucellosis
      9. Chronic Lymphocytic Leukemia
      10. Acute Lymphoblastic Leukemia
    2. Activated Lymphocytes (Atypical lymphocytes)
      1. Cytomegalovirus Infection
      2. Infectious Mononucleosis
      3. Infectious Hepatitis
      4. Toxoplasmosis
      5. Post-transfusion
      6. Medication
        1. Mephenytoin
        2. Dilantin
        3. Para-aminosalicylic acid
  2. Increased Relative Lymphocyte Count
    1. Normal finding in children under age 2 years
    2. Acute stage of viral infection
    3. Connective tissue disease
    4. Hyperthyroidism
    5. Addison's Disease
    6. Splenomegaly

IV. Interpretation: Decreased

  1. AIDS
  2. Bone Marrow suppression
  3. Aplastic Anemia
  4. Neoplasms
  5. Steroids
  6. Adrenocortical hyperfunction
  7. Neurologic Disorders
    1. Multiple Sclerosis
    2. Myasthenia Gravis
    3. Gullain Barre Syndrome

Images: Related links to external sites (from Google)

Ontology: Lymphocyte (C0024264)

Definition (MSH) White blood cells formed in the body's lymphoid tissue. The nucleus is round or ovoid with coarse, irregularly clumped chromatin while the cytoplasm is typically pale blue with azurophilic (if any) granules. Most lymphocytes can be classified as either T or B (with subpopulations of each), or NATURAL KILLER CELLS.
Definition (NCI) Refers to lymphocytes (a type of white blood cell).
Definition (NCI) A type of immune cell that is made in the bone marrow and is found in the blood and in lymph tissue. The two main types of lymphocytes are B lymphocytes and T lymphocytes. B lymphocytes make antibodies, and T lymphocytes help kill tumor cells and help control immune responses. A lymphocyte is a type of white blood cell.
Definition (CSP) white blood cells formed in the body's lymphoid tissue.
Definition (NCI) White blood cells formed in the body's lymphoid tissue. The nucleus is round or ovoid with coarse, irregularly clumped chromatin while the cytoplasm is typically pale blue with azurophilic (if any) granules. Most lymphocytes can be classified as either T or B (with subpopulations of each); those with characteristics of neither major class are called null cells.
Definition (NCI) Of or pertaining to lymphocytes.
Concepts Cell (T025)
MSH D008214
SnomedCT 56972008
HL7 LYM
English Lymphocytes, Lymphocyte, NOS, Lymphocytic cell, NOS, lymphocytes, Lymphocytic, lymphocyte, lymphocytic, Blood lymphocytic cell, Blood lymphocyte, Marrow lymphocyte, lymph cell, Lymphocyte (cell), Lymphocytic cell, Lymphocyte
Dutch lymfocyten, Lymfocyt, Lymfocyten
French Lymphocyte, Lymphocytes, Cellules lymphocytaires
Japanese リンパ球, リンパキュウ
Swedish Lymfocyter
Czech lymfocyty, Lymfocyty
Finnish Imusolut
Russian LIMFOIDNYE KLETKI, LIMFOTSITY, ЛИМФОИДНЫЕ КЛЕТКИ, ЛИМФОЦИТЫ
Croatian LIMFOCITI
Latvian Not Translated[Lymphocytes]
Polish Limfocyty
Hungarian Limfociták
Spanish célula linfática, linfocito (célula), linfocito, Linfocitos
German Lymphozyten
Italian Linfociti
Portuguese Linfócitos

Ontology: Lymphocytosis (C0024282)

Definition (NCI) A laboratory test result indicating an abnormal increase in the number of lymphocytes in the peripheral blood, effusions, or bone marrow.
Definition (NCI) A finding based on laboratory test results that indicate an abnormal increase in the number of lymphocytes in the blood, effusions or bone marrow.
Definition (MSH) Excess of normal lymphocytes in the blood or in any effusion.
Definition (CSP) excess of normal lymphocytes in the blood or in any effusion.
Concepts Disease or Syndrome (T047)
MSH D008218
SnomedCT 67023009, 154832004, 267568006, 418010004
English Lymphocytoses, LYMPHOCYTOSIS, Lymphocytosis, NOS, lymphocytosis (diagnosis), lymphocytosis, Lymphocyte count increased, Lymphocytosis [Disease/Finding], Lymphocytosis, lymphocytose, Lymphocytosis (disorder), Increased blood lymphocyte number (finding), Increased blood lymphocyte number
French LYMPHOCYTOSE, Lymphocytose, Hyperlymphocytose
Portuguese LINFOCITOSE, Linfocitose
Spanish LINFOCITOSIS, cantidad de linfocitos sanguíneos elevada, linfocitosis (hallazgo), Lymphocytosis, linfocitosis (trastorno), linfocitosis, Linfocitosis
German LYMPHOZYTOSE, Lymphozytose
Japanese リンパ球増加症, リンパキュウゾウカショウ
Swedish Lymfocytos
Czech lymfocytóza, Lymfocytóza
Finnish Lymfosytoosi
Russian LIMFOTSITOZ, ЛИМФОЦИТОЗ
Croatian LIMFOCITOZA
Polish Limfocytoza
Hungarian lymphocytosis
Dutch lymfocytose, Lymfocytose
Italian Linfocitosi