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Related to lymphocytopenia: lymphocytosis, leukemia, neutropenia, neutrophilia, thrombocytopenia




Lymphocytopenia is a condition marked by an abnormally low level of lymphocytes in the blood. Lymphocytes are a specific type of white blood cell with important functions in the immune system.


Lymphocytes normally account for 15-40% of all white cells in the bloodstream. They help to protect the body from infections caused by viruses or fungi. They also coordinate the activities of other cells in the immune system. In addition, lymphocytes fight cancer and develop into antibody-producing cells that neutralize the effect of foreign substances in the blood.
Lymphocytopenia is the result of abnormalities in the way lymphocytes are produced, make their way through the bloodstream, or are lost or destroyed. These conditions can result from congenital or drug-induced decreases in the body's ability to recognize and attack invaders.

Causes and symptoms

Lymphocytopenia has a wide range of possible causes:
  • AIDS and other viral, bacterial, and fungal infections
  • Chronic failure of the right ventricle of the heart. This chamber of the heart pumps blood to the lungs.
  • Hodgkin's disease and cancers of the lymphatic system
  • A leak or rupture in the thoracic duct. The thoracic duct removes lymphatic fluid from the legs and abdomen.
  • Leukemia
  • Side effects of prescription medications
  • Malnutrition. Diets that are low in protein and overall calorie intake may cause lymphocytopenia.
  • Radiation therapy
  • High stress levels
  • Trauma.
The symptoms of lymphocytopenia vary. Lymphocytes constitute only a fraction of the body's white blood cells, and a decline in their number may not produce any symptoms. A patient who has lymphocytopenia may have symptoms of the condition responsible for the depressed level of lymphocytes.


Lymphocytopenia is most often detected when blood tests are performed to diagnose other diseases.


Treatment for lymphocytopenia is designed to identify and correct the underlying cause of the condition.
Drug-depressed lymphocyte levels usually return to normal a few days after the patient stops taking the medication.

Key terms

B lymphocyte — A type of lymphocyte that circulates in the blood and lymph and produces antibodies when it encounters specific antigens. B lymphocytes are also called B cells.
Lymph — A clear yellowish fluid circulated by the lymphatic system. The lymph carries mostly lymphocytes and fats.
Lymphocyte — A specific type of white blood cell that is important in the production of antibodies.
A deficiency of B lymphocytes, which mature into antibody-producing plasma cells, can result in abnormally low lymphocyte levels. When the number of B lymphocytes is low, the patient may be treated with antibiotics, antifungal medications, antiviral agents, or a substance containing a high concentration of antibodies (gamma globulin) to prevent infection.
It is not usually possible to restore normal lymphocyte levels in AIDS patients. Drugs like AZT (azidothymidine, sold under the trade name Retrovir) can increase the number of helper T cells, which help other cells wipe out disease organisms.


Very low levels of lymphocytes make patients vulnerable to life-threatening infection. Researchers are studying the effectiveness of transplanting bone marrow and other cells to restore normal lymphocyte levels. Gene therapy, which uses the body's own resources or artificial substances to counter diseases or disorders, is also being evaluated as a treatment for lymphocytopenia.



Berktow, Robert, et al., editors. Merck Manual of Medical Information: Home Edition. Whitehouse Station, NJ: Merck Research Laboratories, 1997.


A reduction, relative or absolute, in the number of lymphocytes in the circulating blood.
[lympho- + G. penia, poverty]


/lym·pho·cy·to·pe·nia/ (-si″to-pe´ne-ah) lymphopenia; reduction of the number of lymphocytes in the blood.


Etymology: L, lympha + Gk, kytos, cell, penes, poor
a decreased number of lymphocytes in the peripheral circulation, associated with immunodeficiency, neoplasm, or chemotherapy. Compare alymphocytosis. See also agranulocyte.


A reduction, relative or absolute, in the number of lymphocytes in the circulating blood.
Synonym(s): lymphocytopenia.
[lympho- + G. penia, poverty]

lymphocytopenia (limˈ·fō·sīˈ·tō·pēˑ·nē·),

n an abnormally low number of lymphocytes in the blood due to malignancy, malnutrition, drugs, infectious mononucleosis, or a primary hematologic disorder.

lymphocytopenia (lim´fōsī´tōpē´nēə),

n a decrease in the normal number of lymphocytes in the circulating blood. Various limits are given (e.g., a total number less than 600/mm3). It may be associated with agranulocytosis, hyperadrenocorticism, leukemia, advanced Hodgkin disease, irradiation, and acute infections with neutrophilia.


see lymphopenia.

lymphopenia, lymphocytopenia

decrease in the number of lymphocytes of the blood.
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It was concluded that regardless of the duration, transport of rabbits under hot humid tropical conditions, resulted in heat distress since the rabbits showed hyperglycemia, hypercalcemia, lactacidemia, lymphocytopenia, dehydration and increase in blood enzyme activities.
2% of the women who received ipriflavone (600 mg/day) developed sub-clinical lymphocytopenia.
2007), the PIR was defined as neutrophilia, lymphocytopenia, and elevated monocytes.
In light of the absolute lymphocytopenia (416 cells/[mm.
Serum IL-6 was also compared with age and gender, Ann Arbor stage, mediastinal involvement, splenomegaly, extranodal disease, bone marrow involvement, bulky disease, leukocytosis, lymphocytopenia, albumin serum levels, lactate dehydrogenase, serum [beta]2 microglobulin, EBV-encoded RNA 1, HL histologic subtype, CD15 and CD20 positivity and response to treatment, but no association was found (Table 1).
Lymphocytopenia is also fairly common but resolves on cessation of treatment.
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The initial diagnosis presumed to be idiopathic CD4+ T-cell lymphocytopenia (ICL) became a diagnosis of AIDS upon isolation of a group O strain of HIV-1, referred to as HIV-1vau.
The most common hematologic laboratory abnormalities in the Xofigo arm (greater than or equal to 10%) vs the placebo arm, respectively, were anemia (93% vs 88%), lymphocytopenia (72% vs 53%), leukopenia (35% vs 10%), thrombocytopenia (31% vs 22%), and neutropenia (18% vs 5%).
Total leukocyte counts in peripheral blood were mostly normal or elevated with lymphocytopenia and anemia also present.
In the 38 patients who developed pneumonia during the study, RSV infection was found to be significantly associated with its development, and lymphocytopenia had a nonsignificant association.
Multiple quinine-dependent antibodies in a patient with episodic thrombocytopenia, neutropenia, lymphocytopenia, and granulomatous hepatitis.