Table of ContentsView AllTable of ContentsSymptomsCausesDiagnostic TestsTreatment
Table of ContentsView All
View All
Table of Contents
Symptoms
Causes
Diagnostic Tests
Treatment
Monocytopeniadescribes a low number of monocytes, a type of white blood cell.Monocytesare made in the bone marrow and account for 2% to 6% of white blood cells at any given time.They work throughout the body as infection-fightingmacrophagesanddendriticcells.Your monocyte count, normally above 100 or below 500 cells per microliter, can be determined with acomplete blood count(CBC).
Monocytopenia usually is associated with abnormalities of other types of white blood cells. This can cause health problems, such as inflammation, severe infections, bleeding, orsymptoms of anemia(including fatigue, dizziness, and pale skin). It also can occur with cancer and other illnesses.
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Monocytopenia can cause symptoms, but symptoms may not result or be noticed, especially early on. When you have low monocytes, this reduces your body’s immune defenses.
Frequent infections are common, which can cause a range of symptoms. These symptoms include:
Thebone marrowproduces monocytes, and any condition that affects the bone marrow can affect the production of monocytes and other white blood cells.
Low monocytes can occur due to:
Cancers that invade the bone marrow, such aschronicmyelomonocytic leukemia(CMML), or diseases that affect bone marrow function, can also cause a low monocyte count.
Common medical treatments can affect monocytes. These causes can include:
Sometimes a low monocyte level is associated with prolonged recovery from an injury.
GATA2 Deficiency
GATA2 deficiency symptoms can begin as early as infancy or as late as adulthood. Symptoms can includelymphadenopathy, warts, and frequent viral, fungal, and bacterial infections, including mycobacterial infection.
It is inherited in an autosomal dominant pattern, meaning that anyone who inherits one gene from one parent for the disease will develop the condition. GATA2 deficiency commonly causes monocytopenia, and it can cause neutropenia (low neutrophils) oraplastic anemia(lack of blood cell production) as well.
This condition can also progress to cause acute myeloid leukemia or chronic myeloid leukemia.
Hairy Cell Leukemia
Hairy cell leukemia is a type of blood cancer in which the body makes too many B-cell lymphocytes. It causes low levels of many types of leukocytes, including a low number of monocytes.
The condition causes an enlarged spleen and a predisposition to infections. This type of cancer can be treated with medication or abone marrow transplant(bone marrow is replaced with healthy stem cells from the recipient or a donor).
If your CBC shows that your monocyte count is low, other tests may be needed to evaluate the cause. These tests can include:
Depending on results, specialist care and testing may be needed.
If you have a low monocyte count on repeat tests, your healthcare provider may recommend infection prevention strategies. These may include staying up to date on recommended immunizations and avoiding places where you could be exposed to infections.
You may also need periodically scheduled CBCs or other tests so that complications, especially leukemia, can be identified and treated at an early stage.Keep in mind that causes of low monocytes are varied, and treatments are based on cause.
Summary
The condition is diagnosed with a CBC and other tests that may be needed to identify the cause. Treatment includes managing complications, treating the underlying condition, and preventing infections.
12 SourcesVerywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.National Cancer Institute.Lab Tests.Mangaonkar AA, Tande AJ, Bekele DI.Differential Diagnosis and Workup of Monocytosis: A Systematic Approach to a Common Hematologic Finding.Curr Hematol Malig Rep. 2021 Jun;16(3):267-275. doi:10.1007/s11899-021-00618-4Nursing 2020 Critical Care.Monocyte Count.Guglietta S, Krieg C.Phenotypic and functional heterogeneity of monocytes in health and cancer in the era of high dimensional technologies.Blood Rev. 2023 Mar;58:101012. doi:10.1016/j.blre.2022.101012Merck Manual.Monocyte Disorders.Fabozzi F, Strocchio L, Mastronuzzi A, Merli P.GATA2 and marrow failure.Best Pract Res Clin Haematol.2021;34(2):101278. doi:10.1016/j.beha.2021.101278Osuka A, Ishihara T, Shimizu K, Shintani A, Ogura H, Ueyama M.Natural kinetics of blood cells following major burn: Impact of early decreases in white blood cells and platelets as prognostic markers of mortality.Burns. 2019;45(8):1901-1907. doi:10.1016/j.burns.2019.07.014Warkentin TE, Morin PA, Heddle NM.Neutropenia and monocytopenia in recurrent anaphylactoid reactions after red blood cell transfusions in a woman with immunoglobulin A (IgA) deficiency and anti-IgA.Transfusion.2018;58(10):2320-2325. doi:10.1111/trf.14894Diamantopoulos PT, Charakopoulos E, Symeonidis A, Kotsianidis I, Viniou NA, Pappa V,et al.Real world data on the prognostic significance of monocytopenia in myelodysplastic syndrome.Sci Rep. 2022 Oct 26;12(1):17914. doi:10.1038/s41598-022-21933-7Patel R, Lima A, Burke C, Hoffman M.Monocytopenia in clozapine-induced agranulocytosis: insights into pathophysiology and treatment.BMJ Case Rep.2019;12(1):bcr-2018-226016. doi:10.1136/bcr-2018-226016Polderdijk MCE, Heron M, Kuipers S, Rijkers GT.Deciphering the genotype and phenotype of hairy cell leukemia: clues for diagnosis and treatment.Expert Rev Clin Immunol. 2019;15(8):857-867. doi:10.1080/1744666X.2019.1641405NIH Genetic and Rare Diseases Information Center.Monocytopenia with susceptibility to infections.
12 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.National Cancer Institute.Lab Tests.Mangaonkar AA, Tande AJ, Bekele DI.Differential Diagnosis and Workup of Monocytosis: A Systematic Approach to a Common Hematologic Finding.Curr Hematol Malig Rep. 2021 Jun;16(3):267-275. doi:10.1007/s11899-021-00618-4Nursing 2020 Critical Care.Monocyte Count.Guglietta S, Krieg C.Phenotypic and functional heterogeneity of monocytes in health and cancer in the era of high dimensional technologies.Blood Rev. 2023 Mar;58:101012. doi:10.1016/j.blre.2022.101012Merck Manual.Monocyte Disorders.Fabozzi F, Strocchio L, Mastronuzzi A, Merli P.GATA2 and marrow failure.Best Pract Res Clin Haematol.2021;34(2):101278. doi:10.1016/j.beha.2021.101278Osuka A, Ishihara T, Shimizu K, Shintani A, Ogura H, Ueyama M.Natural kinetics of blood cells following major burn: Impact of early decreases in white blood cells and platelets as prognostic markers of mortality.Burns. 2019;45(8):1901-1907. doi:10.1016/j.burns.2019.07.014Warkentin TE, Morin PA, Heddle NM.Neutropenia and monocytopenia in recurrent anaphylactoid reactions after red blood cell transfusions in a woman with immunoglobulin A (IgA) deficiency and anti-IgA.Transfusion.2018;58(10):2320-2325. doi:10.1111/trf.14894Diamantopoulos PT, Charakopoulos E, Symeonidis A, Kotsianidis I, Viniou NA, Pappa V,et al.Real world data on the prognostic significance of monocytopenia in myelodysplastic syndrome.Sci Rep. 2022 Oct 26;12(1):17914. doi:10.1038/s41598-022-21933-7Patel R, Lima A, Burke C, Hoffman M.Monocytopenia in clozapine-induced agranulocytosis: insights into pathophysiology and treatment.BMJ Case Rep.2019;12(1):bcr-2018-226016. doi:10.1136/bcr-2018-226016Polderdijk MCE, Heron M, Kuipers S, Rijkers GT.Deciphering the genotype and phenotype of hairy cell leukemia: clues for diagnosis and treatment.Expert Rev Clin Immunol. 2019;15(8):857-867. doi:10.1080/1744666X.2019.1641405NIH Genetic and Rare Diseases Information Center.Monocytopenia with susceptibility to infections.
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
National Cancer Institute.Lab Tests.Mangaonkar AA, Tande AJ, Bekele DI.Differential Diagnosis and Workup of Monocytosis: A Systematic Approach to a Common Hematologic Finding.Curr Hematol Malig Rep. 2021 Jun;16(3):267-275. doi:10.1007/s11899-021-00618-4Nursing 2020 Critical Care.Monocyte Count.Guglietta S, Krieg C.Phenotypic and functional heterogeneity of monocytes in health and cancer in the era of high dimensional technologies.Blood Rev. 2023 Mar;58:101012. doi:10.1016/j.blre.2022.101012Merck Manual.Monocyte Disorders.Fabozzi F, Strocchio L, Mastronuzzi A, Merli P.GATA2 and marrow failure.Best Pract Res Clin Haematol.2021;34(2):101278. doi:10.1016/j.beha.2021.101278Osuka A, Ishihara T, Shimizu K, Shintani A, Ogura H, Ueyama M.Natural kinetics of blood cells following major burn: Impact of early decreases in white blood cells and platelets as prognostic markers of mortality.Burns. 2019;45(8):1901-1907. doi:10.1016/j.burns.2019.07.014Warkentin TE, Morin PA, Heddle NM.Neutropenia and monocytopenia in recurrent anaphylactoid reactions after red blood cell transfusions in a woman with immunoglobulin A (IgA) deficiency and anti-IgA.Transfusion.2018;58(10):2320-2325. doi:10.1111/trf.14894Diamantopoulos PT, Charakopoulos E, Symeonidis A, Kotsianidis I, Viniou NA, Pappa V,et al.Real world data on the prognostic significance of monocytopenia in myelodysplastic syndrome.Sci Rep. 2022 Oct 26;12(1):17914. doi:10.1038/s41598-022-21933-7Patel R, Lima A, Burke C, Hoffman M.Monocytopenia in clozapine-induced agranulocytosis: insights into pathophysiology and treatment.BMJ Case Rep.2019;12(1):bcr-2018-226016. doi:10.1136/bcr-2018-226016Polderdijk MCE, Heron M, Kuipers S, Rijkers GT.Deciphering the genotype and phenotype of hairy cell leukemia: clues for diagnosis and treatment.Expert Rev Clin Immunol. 2019;15(8):857-867. doi:10.1080/1744666X.2019.1641405NIH Genetic and Rare Diseases Information Center.Monocytopenia with susceptibility to infections.
National Cancer Institute.Lab Tests.
Mangaonkar AA, Tande AJ, Bekele DI.Differential Diagnosis and Workup of Monocytosis: A Systematic Approach to a Common Hematologic Finding.Curr Hematol Malig Rep. 2021 Jun;16(3):267-275. doi:10.1007/s11899-021-00618-4
Nursing 2020 Critical Care.Monocyte Count.
Guglietta S, Krieg C.Phenotypic and functional heterogeneity of monocytes in health and cancer in the era of high dimensional technologies.Blood Rev. 2023 Mar;58:101012. doi:10.1016/j.blre.2022.101012
Merck Manual.Monocyte Disorders.
Fabozzi F, Strocchio L, Mastronuzzi A, Merli P.GATA2 and marrow failure.Best Pract Res Clin Haematol.2021;34(2):101278. doi:10.1016/j.beha.2021.101278
Osuka A, Ishihara T, Shimizu K, Shintani A, Ogura H, Ueyama M.Natural kinetics of blood cells following major burn: Impact of early decreases in white blood cells and platelets as prognostic markers of mortality.Burns. 2019;45(8):1901-1907. doi:10.1016/j.burns.2019.07.014
Warkentin TE, Morin PA, Heddle NM.Neutropenia and monocytopenia in recurrent anaphylactoid reactions after red blood cell transfusions in a woman with immunoglobulin A (IgA) deficiency and anti-IgA.Transfusion.2018;58(10):2320-2325. doi:10.1111/trf.14894
Diamantopoulos PT, Charakopoulos E, Symeonidis A, Kotsianidis I, Viniou NA, Pappa V,et al.Real world data on the prognostic significance of monocytopenia in myelodysplastic syndrome.Sci Rep. 2022 Oct 26;12(1):17914. doi:10.1038/s41598-022-21933-7
Patel R, Lima A, Burke C, Hoffman M.Monocytopenia in clozapine-induced agranulocytosis: insights into pathophysiology and treatment.BMJ Case Rep.2019;12(1):bcr-2018-226016. doi:10.1136/bcr-2018-226016
Polderdijk MCE, Heron M, Kuipers S, Rijkers GT.Deciphering the genotype and phenotype of hairy cell leukemia: clues for diagnosis and treatment.Expert Rev Clin Immunol. 2019;15(8):857-867. doi:10.1080/1744666X.2019.1641405
NIH Genetic and Rare Diseases Information Center.Monocytopenia with susceptibility to infections.
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