Leukocytosis



Leukocytosis


David T. Teachey



INTRODUCTION

Leukocytosis is defined as an increase in the total number of white blood cells (WBCs). The normal WBC count varies by age, with infants having the highest total leukocyte count. Leukocytosis may result from an increase in any of the types of WBCs found in the bone marrow. Neutrophilia is most common, but lymphocytosis, monocytosis, basophilia, eosinophilia, and atypical lymphocytosis can also occur. Lymphoblasts or myeloblasts can be seen in abundance in the peripheral blood in leukemia, causing leukocytosis. Leukemoid reactions, which consist of benign but excessive leukocytosis (WBC counts that can be over 50,000/mm3) associated with an increase in the number of immature myeloid cells (blasts, promyelocytes, myelocytes, and metamyelocytes) in the peripheral blood, can also occur.


DIFFERENTIAL DIAGNOSIS LIST


Neutrophilia



  • Infectious Causes



    • Bacterial Infection



      • Staphylococcus


      • Streptococcus


      • Gonococcus


      • Meningococcus


      • Escherichia coli


      • Pseudomonas


      • Corynebacterium diphtheriae


      • Pasteurella


    • Viral Infection



      • Herpes zoster


      • Varicella


      • Rabies


      • Poliomyelitis


      • Epstein-Barr virus (infectious mononucleosis)


    • Fungal Infection



      • Actinomyces


      • Coccidioides


    • Mycobacterial Infection



      • Tuberculosis


    • Rickettsial Infection


    • Spirochetal Infection



      • Leptospira


      • Lyme disease


      • Syphilis


    • Other Infections



      • Kawasaki disease


    • Toxic/Drug/Hormonal Causes



      • Corticosteroids, adrenocorticotrophic hormone


      • Mercury, lead, kerosene, camphor


      • Epinephrine, norepinephrine, serotonin, histamine, acetylcholine


    • Neoplastic Causes



      • Eclampsia


      • Uremia


      • Anorexia



    • Inflammatory Causes



      • Collagen vascular diseases (e.g., rheumatoid arthritis)


      • Acute rheumatic fever


    • Hematologic Causes



      • Hemolysis—associated with both acute hemolysis, as in autoimmune hemolytic anemia, and chronic hemolysis, as in sickle cell anemia


      • Acute blood loss


      • Myeloproliferative disorders


      • Surgical or functional asplenia


      • Leukemoid reaction


  • Miscellaneous Causes



    • Physical Stimuli



      • Burns


      • Pain


      • Electric shock


      • Trauma/surgery


    • Physiologic



      • Pregnancy/labor


      • Ovulation/menstruation


      • Vigorous exercise


      • Emotional stress


Eosinophilia (> 4% of Total WBC Count)



  • Infectious Causes (Especially Parasites)



    • Ascaris infestation


    • Hookworm infestation


    • Strongyloides infestation


    • Trichinosis


    • Visceral larva migrans


    • Filariasis


    • Malaria


    • Toxoplasmosis


    • Pneumocystis carinii


    • Schistosomiasis


    • Scabies


    • Scarlet fever


    • Aspergillosis


    • Coccidioidomycosis


  • Toxic Causes



    • Drug hypersensitivity reaction


    • Postirradiation


  • Neoplastic Causes



    • Leukemia


    • Hodgkin and non-Hodgkin lymphoma


    • Brain tumors


    • Myeloproliferative disorders


  • Inflammatory/Allergic/Immune Conditions



    • Polyarteritis nodosa


    • Sarcoidosis


    • Goodpasture syndrome


    • Milk precipitin disease


    • Enteritis/ulcerative colitis


    • Environmental allergies


    • Asthma


    • Hay fever


    • Urticaria


    • Lymphoproliferative disorders


  • Miscellaneous Causes



    • Hereditary eosinophilia


    • Tropical eosinophilia (syndrome of pulmonary infiltrates, asthmalike symptoms, lymphadenopathy, and eosinophilia thought to be secondary to an unidentified filarial parasite)


    • Peritoneal dialysis


    • Chronic renal or liver disease


    • Immune deficiency syndromes


Monocytosis (>8% to 10% of Total WBC Count in Childhood; >2% of Total WBC Count in Newborn Period)



  • Infectious Causes



    • Tuberculosis


    • Syphilis


    • Brucellosis


    • Malaria


    • Bacterial endocarditis



    • Rocky Mountain spotted fever


    • Typhoid fever


  • Neoplastic Causes



    • Preleukemia


    • Acute myelogenous leukemia (AML)—myelomonocytic and monocytic forms


    • Juvenile myelomonocytic leukemia


    • Chronic myelogenous leukemia


    • Hodgkin and non-Hodgkin lymphoma


  • Inflammatory Causes



    • Systemic lupus erythematosus


    • Rheumatoid arthritis


    • Ulcerative colitis/Crohn disease


    • Sarcoidosis


  • Miscellaneous Causes



    • Chronic neutropenia syndromes (e.g., Kostmann syndrome)


    • Postsplenectomy


Basophilia (> 1% of Total WBC Count)



  • Infectious Causes



    • Varicella


    • Tuberculosis


    • Influenza


  • Neoplastic Causes



    • Chronic myelogenous leukemia


    • Hodgkin disease


  • Inflammatory Causes



    • Ulcerative colitis


    • Rheumatoid arthritis


  • Miscellaneous Causes



    • Asthma


    • Drug hypersensitivity reaction


    • Chronic hemolytic anemia


    • Postsplenectomy or postradiation


Lymphocytosis



  • Infectious Causes (Associated with an Increased Number of Atypical Lymphocytes)



    • Bacterial infection


    • Pertussis*


    • Tuberculosis


    • Brucellosis


    • Typhoid fever


    • Viral infection


    • Infectious mononucleosis (Epstein-Barr virus) †


    • Cytomegalovirus †


    • Acute viral lymphocytosis (with common viral infections) *


    • Infectious hepatitis (A, B, or C)†


    • Rubeola


    • Rubella


    • Mumps


    • Varicella


  • Other Infections



    • Syphilis


    • Toxoplasmosis


  • Miscellaneous Causes



    • Physiologic lymphocytosis (percentage of lymphocytes is greater than percentage of polymorphonuclear leukocytes from 2 to 5 years of age)


    • Relative lymphocytosis (secondary to neutropenia)


    • Endocrine—thyrotoxicosis, Addison disease


    • Drug hypersensitivity reaction


    • Crohn disease/ulcerative colitis


    • Leukemia



DIFFERENTIAL DIAGNOSIS DISCUSSION


Neutrophilia



image HINT: Healthy newborn infants normally experience a period of neutrophilia associated with a “left-shifted” differential (an increase in the percentage of early myeloid forms in the peripheral blood). The peak WBC count occurs during the first few days of life and decreases to adult levels within the first few weeks.

Only gold members can continue reading. Log In or Register to continue

Related posts:

  1. Animal Bites
  2. Diarrhea, Acute
  3. Jaundice, Newborn
  4. Vaginal Bleeding

Stay updated, free articles. Join our Telegram channel
Tags:
Sep 14, 2016 | Posted by in PEDIATRICS | Comments Off on Leukocytosis

Full access? Get Clinical Tree
Get Clinical Tree app for offline access