Libyan Journal of Medical Sciences

: 2019  |  Volume : 3  |  Issue : 2  |  Page : 37-

Overview of leukocyte leukemoid reaction

Bashir Abdrhman Bashir Mohammed 
 Department of Hematology, Medical Laboratory Sciences Division, Port Sudan Ahlia College, Port Sudan, Sudan

Correspondence Address:
Dr. Bashir Abdrhman Bashir Mohammed
Department of Hematology, Medical Laboratory Sciences Division, Port Sudan Ahlia College, Port Sudan

How to cite this article:
Bashir Mohammed BA. Overview of leukocyte leukemoid reaction.Libyan J Med Sci 2019;3:37-37

How to cite this URL:
Bashir Mohammed BA. Overview of leukocyte leukemoid reaction. Libyan J Med Sci [serial online] 2019 [cited 2020 Sep 18 ];3:37-37
Available from:

Full Text

Leukemoid reaction is a reverse hematological reaction defined as a response to severe infection, burns, and other conditions associated with high leukocyte count and smear blood films which resemble those shown in leukemic or subleukemic manifestations.[1] It is a reactive condition secondary to various disorders accompanied by immature leukocyte in the peripheral blood, therefore, the count of leukocytes rarely exceeds 60 × 109/L.[2] Due to alterations in the blood similar to hematological neoplastic disorder, it is necessary to distinguish them from leukemia. Leukemoid reaction is usually apparent with many clinical signs. Leukocytosis associated with leukemoid reaction is transient and may return to normal when causer removed.[3] The leukemoid reaction can be classified depending on the disease course and hematopoietic irritation into myeloid (neutrophilic) leukemoid reaction, lymphoid leukemoid reaction, eosinophilic leukemoid reaction, monocytic leukemoid reaction, and basophilic leukemoid reaction.[4]

Leukemoid reactions resembles chronic myeloid leukemia or chronic neutrophilic leukemia, it is the very common type and may take place in tuberculosis (TB), septicemia, acute megaloblastic anemia during pregnancy, acute hepatic necrosis, burns, and following severe bleeding.[2] These disorders are only examples. Moreover, an acute myeloid leukemia-like can be observed with severe pulmonary or extrapulmonary TB. Leukemoid reaction resembling acute lymphoblastic leukemia is commonly seen in children and can be associated with miliary TB, infectious mononucleosis, measles, syphilis, chickenpox, pertussis, and malarial infection. A chronic lymphocytic leukemia-like blood picture can be illustrated with hyperactive malarial splenomegaly.[2] Eosinophilic leukemoid reaction can be developed in allergic conditions or diseases with allergies and children infected with parasitic diseases. It is characterized by an increment number of eosinophils (90% of leukocytes) accompanied by excess lobulation of nuclei.[5] Monocytic leukemoid reaction is purely rare condition. The monocytes and promonocyte form accounting 30% or more of the total circulating blood leukocytes. This condition may be associated with miliary TB and in some cases reported with myelodysplasia treated with glucocorticoid.[6] Basophilic leukemoid reactions are rare type. Reactive basophilia may take place in allergic reactions, primary polycythemia, inflammatory bowel disease, and hypothyroidism as well as some hemolytic anemia.[5]

I'm sure that this view will add to the body of knowledge on the significant types of leukemoid reaction in clinical practice and the importance of differentiating them from other resembling conditions.

Financial support and sponsorship


Conflicts of interest

There are no conflicts of interest.


1Nimieri HS, Makoni SN, Madziwa FH, Nemiary DS. Leukemoid reaction response to chemotherapy and radiotherapy in a patient with cervical carcinoma. Ann Hematol 2003;82:316-7.
2Cheesbrough M. District Laboratory Practice in Tropical Countries. Low Price edition. Part 2. U.K: Cambridge. Org.; 2001. p. 291-3.
3Shalom G, Sion-Vardy N, Dudnik J, Ariad S. Leukemoid reaction in lung cancer patients. Isr Med Assoc J 2010;12:255-6.
4Gonchar MO, Ishchenko TB, Koval VA. Mean features of leukemoid reaction in children. Int Coll J 2016;3:8-11.
5Sakka V, Tsiodras S, Giamarellos-Bourboulis EJ, Giamarellou H. An update on the etiology and diagnostic evaluation of a leukemoid reaction. Eur J Intern Med 2006;17:394-8.
6Hoofien A, Yarden-Bilavski H, Ashkenazi S, Chodick G, Livni G. Leukemoid reaction in the pediatric population: Etiologies, outcome, and implications. Eur J Pediatr 2018;177:1029-36.