Version 2.77

Term Description

In the Hematology world estimated cell counts have existed for many moons and they are reported either qualitatively or quantitatively and done strictly by blood smear review.

Smear Estimated WBC and Platelet counts that aren't just reported as reduced/adequate/many that are actually estimated as a numeric result like an estimate of 4 K/cumm for WBC or 400 K/cumm for platelets. Like doing a retic count by counting so many fields on the smear type of estimate.

This WBC estimate count is a manual quantitative count. We report a number.
See laboratory procedure:

A. WBC Count Smear Estimate:

1. Use the 50X oil immersion objective.
2. Count the number of both intact and disrupted WBCs in each of 10 microscopic fields in different areas of the slide where RBCs slightly overlap. Divide the total number by 10 to establish the mean number of WBCs/field and multiply this mean by 3,000 to get the estimated WBC count/mm³. Do not round off the mean, e.g., if the mean is 5.7 do not round off to 6 but leave the figure at one place past the decimal point for greater accuracy.
3. If the quantitative WBC count is <25,000, the estimated smear count should be within 1,500 cells of this figure. Estimate counts are less reliable at >25,000 cells/mm³.


A. A Color Atlas and Instruction Manual of Peripheral Blood Cells Morphology, by Barbara H. O'Connor, 1984, p. 20.
B. Principles and Procedures, Barbara A. Brown, 6th Edition, 1993, p. 104.
Source: Regenstrief LOINC

Part Description

LP14419-3   Leukocytes
Leukocytes or white blood cells (WBCs) are immune cells that fight infection, neoplasms and other inflammatory conditions, and mediate allergic responses. There are five types of WBCs normally present in the circulation that are all derived from a similar stem cell in the bone marrow. The five type of WBCs are divided into two groups based on the presence or absence of granules in the cytoplasm. The granulocytes include the neutrophils, basophils and eosinophils. The non-granulocytes include the lymphocytes and the monocytes. The neutrophils fight infection by ingesting and digesting bacteria. Eosinophils and basophils respond to allergic reactions and are capable of ingesting antigen-antibody complexes. Monocytes phagocytose bacteria and release interferon to stimulate the immune system. Lymphocytes are divided into T-cells and B-cells. T-cell immunity is cellular and involves the activation of phagocytes and B-cell immunity uses antibodies to fight infection. Both elevated and low leukocyte counts can be markers of infection and malignancy, and low leukocyte counts are associated with a variety of primary and secondary immunodeficiencies, depending on the WBC type(s) that are out of range. (Mosby's manual of diagnostic and laboratory tests, Kathleen Deska Pagana; Timothy James Pagana, Elsevier St. Louis, Mo ©2010) Source: Regenstrief LOINC

Reference Information

Type Source Reference
Webcontent Lab Tests Online®Copyright Copyright © 2021 Lab Tests Online. All rights reserved. White Blood Cell Count (WBC)

Fully-Specified Name


Additional Names

Short Name
WBC # Bld Est
Display Name
WBC Estimate (Bld) [#/Vol]
Consumer Name Alpha Get Info
White blood cell (WBC) count, Blood

Basic Attributes

First Released
Version 2.22
Last Updated
Version 2.73
Order vs. Observation
Common Test Rank Get Info

Member of these Groups Get Info

LOINC Group Group Name
LG32857-1 Leukocytes|NCnc|Pt|Bld

Language Variants Get Info

Tag Language Translation
de-DE German (Germany) Leukozyten:Anzahl pro Volumen:Zeitpunkt:Blut:Quantitativ:Schätzung
es-ES Spanish (Spain) Leucocitos:Concentración de número:Punto temporal:Sangre:Qn:Estimación
Synonyms: Cuantitativo
es-MX Spanish (Mexico) Leucocitos:Concentración numérica:Punto temporal:Sangre:Cuantitativo:Estimar
fr-CA French (Canada) Leucocytes:Concentration numérique:Temps ponctuel:Sang:Quantitatif:Estimé
fr-FR French (France) Leucocytes:Nombre/Volume:Ponctuel:Sang:Numérique:Estimation
fr-BE French (Belgium) Leucocytes:Concentration numérique:Temps ponctuel:Sang:Quantitatif:Estimation
it-IT Italian (Italy) Leucociti:NCnc:Pt:Sangue:Qn:Stima
Synonyms: Concentrazione Numerica Ematologia (coagulazione) conta differenziale Punto nel tempo (episodio) Sangue
nl-NL Dutch (Netherlands) leukocyten:aantal/volume:moment:bloed:kwantitatief:schatting
pl-PL Polish (Poland) Leukocyty:stężenie liczbowe:punkt w czasie:krew:ilościowy:szacowanie
Synonyms: koncentracja Leukocyty
pt-BR Portuguese (Brazil) Leucócitos:NCnc:Pt:SgTotal:Qn:Estimado
Synonyms: ; Leucoc; White blood cell; Leuc; Leuk; Leukocyte; Lkcs; White blood cells; Leucocs; #; Number concentration; Count/mass; Count; AcS; CT; Acsolute; Acsolutes; Cnt; Point in time; Random; Blood; WB; Whole blood; Quantitative; QNT; Quant; Quan; Est; estimation; HEMATOLOGY/CELL COUNTS; HEMATOLOGY/CELL COUNTS
tr-TR Turkish (Turkey) Lökositler:SayKons:Zmlı:Kan:Kant:Hesap
zh-CN Chinese (China) 白细胞:计数型浓度:时间点:全血:定量型:估计法
Synonyms: Leuc;Leuk;Lkcs;WBC;WBCs;白细胞;White blood cell;WBC;白细胞类;白细胞类髓系细胞;白血球;白血细胞;白细胞数 估算;估算法;估计 单位体积内的数量或计数;数量型浓度(单位体积);数量或计数型浓度(计数/体积);数量或计数型浓度(单位体积);计数型浓度(单位体积) 可用数量表示的;定量性;数值型;数量型;连续数值型标尺 时刻;随机;随意;瞬间 血;血液 血液学/细胞计数;血液学与细胞计数

Example Units

Unit Source
10*3/uL Example UCUM Units

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