Eosinophil Count
| Eosinophil Count | | | |
| Number | | 005298 |
| CPT | | 85048 |
| Synonyms | | Absolute Eosinophil Count ; Eos Count ; Total Eosinophil Count |
| Test Includes | | Enumeration of eosinophils with a cell counter |
| Specimen | | Whole blood |
| Volume | | 3 mL (dependent upon whether cells are badly distorted by excess anticoagulant) |
| Container | | Lavender-top (EDTA) tube |
| Collection | | Invert immediately and mix with anticoagulant. |
| Storage Instructions | | Maintain specimen at room temperature up to 24 hours. |
| Causes for Rejection | | Hemolysis; clotted specimen; tube not filled with minimum volume; improper labeling |
| Use | | Usually increased in allergy, parasitic infestations, tuberculosis, brucellosis, collagen disease, Hodgkin disease, myeloproliferative diseases, and the acute hypereosinophilic syndrome; increased also in angioneurotic edema, dermatitis, thymic disorders, radiotherapy, splenectomy, convalescence from a febrile illness, and hypoadrenocorticism (Addison disease). Decreased eosinophils occurs in adrenal cortical hyperplasia (Cushing syndrome), cortisone therapy, hormone-secreting tumors, intermenstrual period, acute and chronic inflammation, and anoxia. |
| Methodology | | Automated cell counter |
| Additional Information | | Toxocaral disease (visceral larva migrans) is a typical parasitic disease in which eosinophil counts (eosinophils >30% on differential) are usually elevated. Taylor et al1 point out, however, that up to 27% of children with toxocariasis have normal eosinophil counts. Thus, normal eosinophil counts do not rule out toxocaral disease or other parasitic infestations. The cytokine interleukin 5 appears to induce eosinophilia in patients with certain parasitic diseases.2 An important although rare cause of increased eosinophils in the peripheral blood is the acute hypereosinophilic syndrome (HES). Reported mortalities ranged from 81% to 95% in 1-3 years. The HES syndrome includes high peripheral WBC count, circulating early eosinophilic forms without blast cells, mental confusion, delusions, near coma, and severe cardiac symptoms. Consistently associated with a poor prognosis are WBC count ≥90,000/mm3, blast forms in blood, heart failure, and severe CNS symptoms (confusion, organic psychosis and coma). This condition may not be a true leukemic myeloproliferative disease, although concepts of HES are controversial. Infiltrative lung diseases, in which peripheral blood eosinophils may be increased, include eosinophilic pneumonia, Löffler syndrome (often related to Ascaris infestation), and tropical eosinophilia (usually related to filariasis).3 Eosinophilic gastroenteritis may occur with blood eosinophilia.4 Eosinophilia myalgia syndrome (EMS) characterized by an eosinophil count of 2000 cells/mm3 or more and severe often incapacitating myalgia is possibly associated with the use of L-tryptophan-containing products (LTCPs). Further definition of this syndrome, causal association between LTCPs and EMS, and modifying etiologic factors/cofactors has been recommended and is being pursued by CDC.5,6 EMS is potentially fatal (Guillain-Barré like ascending polyneuropathy) with a clinical course resembling the toxic oil syndrome that was epidemic in Spain in 1981.7 |
| Footnotes | | - Taylor MR, Keane CT, O'Connor P, et al, “The Expanded Spectrum of Toxocaral Disease,” Lancet, 1988, 1(8587):692-5.
- Limaye AP, Abrams JS, Silver JE, et al, “Regulation of Parasitic Induced Eosinophilia: Selectively Increased Interleukin-5 Production in Helminth-Infected Patients,” J Exp Med, 1990, 172(1):399-402.
- Colby TV and Carrington CB, “Infiltrative Lung Disease,” Chapter 20, Pathology of the Lung, Thurlbeck WM, ed, New York, NY: Thieme Medical Publishers, Inc, 1988, 425-517.
- Pavli P and Doe WF, “The Alimentary Tract in Disorders of the Immune System,” Gastrointestinal and Oesophageal Pathology, Whitehead R, ed, Edinburgh, England: Churchill Livingstone, 1989, 187.
- Centers for Disease Control, “Eosinophilia-Myalgia Syndrome - New Mexico,” MMWR, 1989, 38(45):765-7.
- Centers for Disease Control, “Eosinophilia-Myalgia Syndrome and L-Tryptophan-Containing Products - New Mexico, Minnesota, Oregon and New York,” MMWR, 1989, 38(46):785-8.
- Kilbourne EM, Rigau-Perez JG, Heath CW Jr, et al, “Clinical Epidemiology of Toxic-Oil Syndrome: Manifestations of a New Illness,” N Engl J Med, 1983, 309(23):1408-14
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