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Related to leukocytosis: digestive leukocytosis




Leukocytosis is a condition characterized by an elevated number of white cells in the blood.


Leukocytosis is a condition that affects all types of white blood cells. Other illnesses, such as neutrophilia, lymphocytosis, and granulocytosis, target specific types of white blood cells. Normal white blood cell counts are 4,300-10,800 white blood cells per microliter. Leukocyte or white blood cell levels are considered elevated when they are between 15,000-20,000 per microliter. The increased number of leukocytes can occur abnormally as a result of an infection, cancer, or drug intake; however, leukocytosis can occur normally after eating a large meal or experiencing stress.

Causes and symptoms

Leukemias can cause white blood cell counts to increase to as much as 100,000. Each kind of white cell can produce a leukemia. Apart from leukemias, nearly all leukocytosis is due to one type of white blood cell, the polymorphonuclear leukocyte (PMN). These conditions are more accurately referred to as neutrophilia.
The most common and important cause of neutrophilia is infection, and most infections cause neutrophilia. The degree of elevation often indicates the severity of the infection. Tissue damage from other causes raises the white count for similar reasons. Burns, infarction (cutting off the blood supply to a region of the body so that it dies), crush injuries, inflammatory diseases, poisonings, and severe diseases, like kidney failure and diabetic ketoacidosis, all cause neutrophilia.
Counts almost as high occur in leukemoid (leukemia-like) reactions caused by infection and non-infectious inflammation.
Drugs can also cause leukocytosis. Cortisone-like drugs (prednisone), lithium, and NSAIDs are the most common offenders.
Non-specific stresses also cause white blood cells to increase in the blood. Extensive testing of medical students reveals that neutrophilia accompanies every examination. Vigorous exercise and intense excitement also cause elevated white blood cell counts.


A complete blood count (CBC) is one of the first tests obtained in any medical setting. More than 11,000 white cells in a cubic millimeter of blood is considered high. Bone marrow biopsy may help clarify the cause.


Relieving the underlying cause returns the count to normal.

Key terms

Biopsy — Surgical removal of tissue for examination.
Inflammation — Heat, swelling, redness, and pain caused by tissue injury.
Ketoacidosis — A severe stage of diabetes where acids and ketones accumulate in the body.
NSAID — Non-steroidal anti-inflammatory drug such as ibuprofen.


By treating the underlying condition, white blood cell counts usually return to normal



Holland, Steven M., and John I. Gallin. "Disorders of Granulocytes and Monocytes." In Harrison's Principles of Internal Medicine, edited by Anthony S. Fauci, et al. New York: McGraw-Hill, 1997.
Gale Encyclopedia of Medicine. Copyright 2008 The Gale Group, Inc. All rights reserved.


a transient increase in the number of leukocytes in the blood, due to various causes.
basophilic leukocytosis basophilia (def. 1).
eosinophilic leukocytosis eosinophilia (def. 1).
mononuclear leukocytosis mononucleosis.
neutrophilic leukocytosis neutrophilia.
pathologic leukocytosis that due to some morbid condition, such as infection or trauma.
physiologic leukocytosis that caused by nonpathologic factors such as strenuous exercise.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.


An abnormally large number of leukocytes, as observed in acute infections, inflammation, hemorrhage, and other conditions. A white blood cell count of 10,000/mm3 (or more) usually indicates leukocytosis Most examples of leukocytosis represent a disproportionate increase in the number of cells in the neutrophilic series, and the term is frequently used synonymously with the designation neutrophilia. Leukocytosis of 15,000-25,000/mm3 is frequently observed in various pathologic conditions, and values as high as 40,000 are not unusual; occasionally, as in some examples of leukemoid reactions, white blood cell counts may range up to 100,000/mm3.
[leukocyte + G. -osis, condition]
Farlex Partner Medical Dictionary © Farlex 2012




n. pl. leukocyto·ses (-sēz)
An abnormally large increase in the number of white blood cells in the blood, often occurring during an acute infection or inflammation.

leu′ko·cy·tot′ic (-tŏt′ĭk) adj.
The American Heritage® Medical Dictionary Copyright © 2007, 2004 by Houghton Mifflin Company. Published by Houghton Mifflin Company. All rights reserved.


↑ in WBCs–WBC count > 11 x 109/L–US: 11,000/mm3, benign or malignant. See Reactive leukocytosis, WBC. Cf Leukemia, Leukopenia.
Physiologic Follows nonspecific immune stimulation, eg intense exercise; it may be idiopathic or hereditary, neonatal, induced by heat or solar irradiation, diurnal, ↑ in afternoon, related to stress, eg pain, nausea, vomiting, anxiety, womanhood–↑ during ovulation and near term, ↑ during labor, ether anesthesia, ↑ adrenalin, convulsions, paroxysmal tachycardia, pain, nausea, vomiting, anoxia, exercise, convulsions
Pathologic May be due to infections, often bacterial, inflammation, severe burns, post-operative, MI, strangulated hernias, intestinal obstruction, gouty attacks, acute glomerulonephritis, serum sickness, rheumatic fever, immune disorders and connective tissue diseases, metabolism–ketoacidosis, uremia, eclampsia, heavy metals–lead, mercury, petrochemicals–benzene, turpentine, drugs–phenacetin, digitalis, black widow spider venom, endotoxin or toxoid injection, Jarisch-Herxheimer reaction, hemorrhage–often into cranial cavity, serosal surfaces–pleural pericardium and peritoneum or acute hemolysis, malignancy–GI tract or hematopoietic, and Cushing syndrome
McGraw-Hill Concise Dictionary of Modern Medicine. © 2002 by The McGraw-Hill Companies, Inc.


An actual increase in the total number of leukocytes in the blood, as distinguished from a relative increase (e.g., in dehydration).
Synonym(s): leucocytosis.
[leukocyte + G. -osis, condition]
Medical Dictionary for the Health Professions and Nursing © Farlex 2012


An abnormally large number of leukocytes, as observed in acute infections, inflammation, hemorrhage, and other conditions.
Synonym(s): leucocytosis.
[leukocyte + G. -osis, condition]
Medical Dictionary for the Dental Professions © Farlex 2012
References in periodicals archive ?
Results of a CBC showed continued improvement of the leukocytosis (31 000 cells/(xL) with no toxic changes.
Baum et al., "Perigraft air, fever, and leukocytosis after endovascular repair of abdominal aortic aneurysms," The American Journal of Surgery, vol.
Rapidly relapsing squamous cell carcinoma of the renal pelvis associated with paraneoplastic syndromes of leukocytosis, thrombocytosis and hypercalcemia.
Although the picture of pneumonia in our patient might be related with Ebstein-Barr virus, it was thought that it would be appropriate to continue parenteral antibiotic treatment because of presence of poor general status, leukocytosis and possibility of bacterial co-infection.
The laboratory findings presented significantly higher percentage of leukocytosis for age, neutrophilic leukocytosis for age, and positive CRP in E.
Other findings include cough, wheezing, bronchopneumonia, anaemia, leukocytosis, and positive Toxocara serology.
Blood examination revealed moderate leukocytosis (white blood cell count: 11,200/mm3; reference range: 4,200-9,000/mm3), a serum glucose level of 326 mg/dl (normal range, 70-125 mg/dl), a serum bilirubin level of 0.32 mg% (normal range, 0.7-1.1 mg%), a serum alkaline phosphatase level of 80 IU (normal range, 40-125 IU), and a serum CRP level of 0.66 mg/dl (normal range, 0-0.5 mg/dl).
The women were split into two groups: 212 met criteria for suspected triple I (documented fever plus clinical signs of intrauterine infection such as maternal leukocytosis greater than 15,000 per [mm.sup.3], fetal tachycardia greater than 160 beats per minute, and purulent amniotic fluid) and 127 met criteria for isolated maternal fever.
The cere lesion improved and no evidence of systemic granulomas was observed over 4 months of treatment, although leukocytosis and monocytosis persisted.
Laboratory tests revealed leukocytosis, elevated C-reactive protein (CRP) and aspartate aminotransferase (AST) levels whereas other biochemical values were within normal limits.