II. Definition

  1. White Blood Cell Count over 10,000/mm3

III. Causes: Cell line specific causes

  1. Neutrophilia (most common cause)
  2. Lymphocytosis
  3. Monocytosis
  4. Eosinophilia (rarely causes Leukocytosis)

IV. Causes: Benign Syndromes

  1. Leukemoid Reaction
    1. WBC Count exceeds 50,000
    2. Cause not involving Bone Marrow
    3. Usually due to non-malignant cause
  2. Reactive Leukocytosis
    1. Fever
    2. Focal infectious signs
    3. Normal Platelet Count and Hemoglobin

V. Causes: Malignancy

  1. Acute Leukemia
    1. Thrombocytopenia
    2. Peripheral Smear with many immature cells (blasts)
    3. Marrow hypercellular with >30% blast cells
    4. Hyperuricemia
  2. Chronic Leukemia
    1. Normal Platelet Count and Hemoglobin

VI. Red flag signs of Bone Marrow disease

  1. Lab abnormalities
    1. Anemia
    2. Thrombocytopenia
    3. Severe Leukocytosis
      1. WBC Count >30,000/mm3 suggests marrow abnormality
      2. WBC Count >100,000/mm3 (urgent hematology consult)
  2. Recent History
    1. Serious Infection
    2. Immunosuppression
    3. Weight loss
  3. Physical Findings
    1. Lymphadenopathy
    2. Splenomegaly
    3. Hepatomegaly
    4. Bleeding, Ecchymosis, or Petechiae
    5. Lethargy

VIII. References

  1. Saiki in Friedman (1991) Medical Diagnosis, p. 227
  2. Abramson (2000) Am Fam Physician 62(9):2053-60

Images: Related links to external sites (from Google)

Ontology: Leukemoid Reaction (C0023501)

Definition (MSH) A peripheral blood picture resembling that of leukemia or indistinguishable from it on the basis of morphologic appearance alone. (Dorland, 27th ed)
Concepts Disease or Syndrome (T047)
MSH D007955
ICD9 288.62
ICD10 D72.823
SnomedCT 56478004
English Leukemoid Reaction, Leukemoid Reactions, Reactions, Leukemoid, LEUKAEMOID REACTION, LEUKEMOID REACTION, REACTION LEUKEMOID, Reaction, Leukemoid, Leukemoid reaction, NOS, Leukemoid reactions, leukemoid reaction (diagnosis), leukemoid reaction, Reaction leukemoid, Leukemoid reaction NOS, Leukemoid Reaction [Disease/Finding], leukemoid reactions, Leukemoid reaction, Leukaemoid reaction, Leukemoid reaction (disorder), leukemoid; reaction, reaction; leukemoid
French REACTION LEUCEMOIDE, Etat pseudoleucémique, Leucemoïde, réaction, Réaction leucémoïde
German LEUKAEMOIDE REAKTION, Reaktion leukomoid, leukaemoide Reaktion, Leukämoide Reaktion
Dutch reactie leukemoïd, leukemoïd; reactie, reactie; leukemoïd, leukemoïde reactie, Leukemoïde reactie, Reactie, leukemoïde
Japanese 類白血病反応, ルイハッケツビョウハンノウ
Swedish Leukemoid reaktion
Czech leukemoidní reakce, Leukemoidní reakce
Finnish Leukemoidireaktio
Russian LEIKEMOIDNYE REAKTSII, ЛЕЙКЕМОИДНЫЕ РЕАКЦИИ
Spanish LEUCEMOIDE, REACCION, reacción leucemoide (trastorno), reacción leucemoide, Reacción leucemoide, Reacción Leucemoide, Reaccion Leucemoide
Portuguese REACCAO LEUCEMOIDE, Reacção leucemóide, Reação Leucemóide
Polish Reakcja białaczkopodobna
Hungarian leukaemoid reakció, Leukemoid reakció
Italian Reazione leucemoide

Ontology: Leukocytosis (C0023518)

Definition (MSH) A transient increase in the number of leukocytes in a body fluid.
Definition (CSP) transient increase in the number of leukocytes in a body fluid.
Concepts Pathologic Function (T046)
MSH D007964
ICD9 288.60
ICD10 D72.829
SnomedCT 142918008, 111583006, 154832004, 191364006, 191368009, 267568006, 414478003
English Leukocytoses, LEUKOCYTOSIS, Leucocytosis, NOS, Leukocytosis (Leucocytosis), Leukocytosis, NOS, Leukocytosis, unspecified, leukocytosis (diagnosis), leukocytosis, Leucocytosis (finding), Leucocytosis NOS, Leukocytosis, Leukocytosis NOS, Leukocytosis [Disease/Finding], leucocytosis, leukocytoses, Leucocytosis, Leukocytosis (disorder), Increased blood leukocyte number (finding), Increased blood leukocyte number, Increased blood leucocyte number
French LEUCOCYTOSE, Leucocytose SAI, Leucocytose, Hyperleucocytose
Portuguese LEUCOCITOSE, Leuocitose NE, Leucocitose
Spanish LEUCOCITOSIS, Leucocitosis NEOM, Leucocytosis, Leukocytosis, leucocitosis (trastorno), leucocitosis, aumento del número de leucocitos en sangre (hallazgo), aumento del número de leucocitos en sangre, Leucocitosis
German LEUKOZYTOSE, Leukozytose NNB, Leukozytose
Dutch leukocytose NAO, leukocytose, Leukocytose
Italian Leucocitosi NAS, Leucocitosi
Japanese 白血球増加症NOS, 白血球増加症, ハッケッキュウゾウカショウNOS, ハッケッキュウゾウカショウ
Swedish Leukocytos
Czech leukocytóza, Leukocytóza, Leukocytóza NOS
Finnish Leukosytoosi
Russian LEIKOTSITOZ, ЛЕЙКОЦИТОЗ
Croatian Not Translated[Leukocytosis]
Polish Leukocytoza
Hungarian leukocytosis, Leukocytosis k.m.n.