WordNet

small room in which a monk or nun lives (同)cubicle
a device that delivers an electric current as the result of a chemical reaction (同)electric cell
a room where a prisoner is kept (同)jail cell, prison cell
(biology) the basic structural and functional unit of all organisms; they may exist as independent units of life (as in monads) or may form colonies or tissues as in higher plants and animals
any small compartment; "the cells of a honeycomb"
a small unit serving as part of or as the nucleus of a larger political movement (同)cadre
the spatial or geographic property of being scattered about over a range, area, or volume; "worldwide in distribution"; "the distribution of nerve fibers"; "in complementary distribution" (同)dispersion
the act of distributing or spreading or apportioning
the commercial activity of transporting and selling goods from a producer to a consumer
(statistics) an arrangement of values of a variable showing their observed or theoretical frequency of occurrence (同)statistical_distribution
smear with blood, as in a hunting initiation rite, where the face of a person is smeared with the blood of the kill
temperament or disposition; "a person of hot blood"
people viewed as members of a group; "we need more young blood in this organization"
the fluid (red in vertebrates) that is pumped through the body by the heart and contains plasma, blood cells, and platelets; "blood carries oxygen and nutrients to the tissues and carries away waste products"; "the ancients believed that blood was the sea
of a color at the end of the color spectrum (next to orange); resembling the color of blood or cherries or tomatoes or rubies (同)reddish, ruddy, blood-red, carmine, cerise, cherry, cherry-red, crimson, ruby, ruby-red, scarlet
red color or pigment; the chromatic color resembling the hue of blood (同)redness
the extent of something from side to side (同)breadth

PrepTutorEJDIC

(刑務所の)『独房』;(修道院の)小さい独居室 / (ミツバチの)みつ房,巣穴 / 小さい部屋 / 『細胞』 / 電池 / 花粉室 / (共産党などの)細胞
〈U〉(…への)『配分』,『分配』,配布,配達《+『to』+『名』》 / 〈U〉分布;分布区域 / 〈C〉配分されたもの,配給品 / 〈U〉(商品の)流通[組織,機構]
『血』,『血』液 / 流血(bloodshed);殺人 / 気質,気性,血気,血潮 / 『血統』,血縁(kinship);生まれ,家柄;《the~》王家の血統 / (人種・出身国の)系 / 〈人〉‘に'初めての経験をさせる / 〈猟犬〉‘に'初めて獲物を血を味わわせる
〈U〉〈C〉『赤,』『赤色;』赤い絵の具(染料) / 〈U〉赤い服 / 〈C〉《しばしば『R-』》《話》《時に軽べつして》アカ,共産主義者;過激論(主義)者 / 〈U〉《通例the ~》(会計の)赤字,負債 / 『赤い』,赤色の / (顔・目などが)赤くなった;血に染った / 赤い服を着た;赤毛の / 《しばしば『R-』》《話》《軽べつして》共産主義の;過激な
〈U〉〈C〉(幅の)『広さ』,幅,横 / 〈C〉一定の幅のもの(織物)

Wikipedia preview

出典(authority):フリー百科事典『ウィキペディア（Wikipedia）』「2014/12/22 08:08:21」(JST)

wiki en

Human red blood cells

Red blood cell distribution width (RDW or RCDW) is a measure of the variation of red blood cell (RBC) volume that is reported as part of a standard complete blood count. Usually red blood cells are a standard size of about 6-8 μm in diameter. Certain disorders, however, cause a significant variation in cell size. Higher RDW values indicate greater variation in size. Normal reference range in human red blood cells is 11.5-14.5%.^[1] If anemia is observed, RDW test results are often used together with mean corpuscular volume (MCV) results to determine the possible causes of the anemia. It is mainly used to differentiate an anemia of mixed causes from an anemia of a single cause. Deficiencies of Vitamin B₁₂ or folate produce a macrocytic anemia (large cell anemia) in which the RDW is elevated in roughly two-thirds of all cases; however, a varied size distribution of red blood cells is a hallmark of iron deficiency anemia, and as such shows an increased RDW in virtually all cases. In the case of a mixed iron and B₁₂ deficiency, there will normally be a mix of both large cells and small cells, causing the RDW to be elevated. An elevated RDW (red blood cells of unequal sizes) is known as anisocytosis.^[2] An elevation in the RDW is not characteristic of all anemias; anemia of chronic disease, hereditary spherocytosis, acute blood loss, aplastic anemia (anemia resulting from an inability of the bone marrow to produce red blood cells), and certain hereditary hemoglobinopathies (including some cases of thalassemia minor) all may present with a normal RDW.^[3]

Calculations

The "width" in RDW is sometimes thought of as "misleading," since it in fact is a measure of deviation of the volume of RBCs, and not directly the diameter. However, "width" refers to the width of the volume curve (distribution width), not the width of the cells. Thus, it is a reasonably accurate term.^[4]^[5]

Mathematically the RDW is calculated with the following formula:

RDW = (Standard deviation of MCV ÷ mean MCV) × 100.^[6]

Pathological Implications

Normal RDW

When anemia is seen in the presence of a normal RDW, one must have a high suspicion towards Thalassemia as the cause of anemia and a Mentzer Index should be done from the CBC report itself to confirm.

High RDW

Iron Deficiency Anemia: usually presents with high RDW with low MCV

Folate and vitamin B12 deficiency anemia: usually presents with high RDW and high MCV

Mixed Deficiency (Iron + B12 or folate) anemia: usually presents with high RDW with MCV being high, low or often normal range

Recent Hemorrhage: typical presentation is high RDW with normal MCV

A false high RDW reading can occur if EDTA anticoagulated blood is used instead of citrated blood. See Pseudothrombocytopenia.

References

^ "Red Cell Distribution Width". Family Practice Notebook. Retrieved 18 October 2013.
^ The red blood cell distribution width.
^ Table 1.4 in: Kjeldsberg, Carl R.; Perkins, Sherrie L.. Practical Diagnosis of Hematologic Disorders. American Society for Clinical Pathology. ISBN 089189571X. 5th edition.
^ Pomeranian Medical University > Red blood cell indices (indexes) Retrieved on 5 April 2009
^ Cornell University, Department of Population Medicine & Diagnostic Sciences > Red Cell Distribution Width (RDW) Last Updated: June 2000. Retrieved on 5 April 2009
^ Encyclopedia of Surgery: A Guide for Patients and Caregivers Red blood cell indices Retrieved on 5 April 2009

UpToDate Contents

全文を閲覧するには購読必要です。 To read the full text you will need to subscribe.

1. 平均赤血球容積 mean corpuscular volume
2. 貧血を有する成人患者に対するアプローチ approach to the adult patient with anemia
3. 貧血を有する小児に対するアプローチ approach to the child with anemia
4. 自動血液分析装置 automated hematology instrumentation
5. 赤血球細胞の力学 red blood cell mechanics

English Journal

Genome-wide association analysis of red blood cell traits in African Americans: the COGENT Network.

Chen Z, Tang H, Qayyum R, Schick UM, Nalls MA, Handsaker R, Li J, Lu Y, Yanek LR, Keating B, Meng Y, van Rooij FJ, Okada Y, Kubo M, Rasmussen-Torvik L, Keller MF, Lange L, Evans M, Bottinger EP, Linderman MD, Ruderfer DM, Hakonarson H, Papanicolaou G, Zonderman AB, Gottesman O; BioBank Japan Project, CHARGE Consortium, Thomson C, Ziv E, Singleton AB, Loos RJ, Sleiman PM, Ganesh S, McCarroll S, Becker DM, Wilson JG, Lettre G, Reiner AP.AbstractLaboratory red blood cell (RBC) measurements are clinically important, heritable and differ among ethnic groups. To identify genetic variants that contribute to RBC phenotypes in African Americans (AAs), we conducted a genome-wide association study in up to ∼16 500 AAs. The alpha-globin locus on chromosome 16pter [lead SNP rs13335629 in ITFG3 gene; P < 1E-13 for hemoglobin (Hgb), RBC count, mean corpuscular volume (MCV), MCH and MCHC] and the G6PD locus on Xq28 [lead SNP rs1050828; P < 1E - 13 for Hgb, hematocrit (Hct), MCV, RBC count and red cell distribution width (RDW)] were each associated with multiple RBC traits. At the alpha-globin region, both the common African 3.7 kb deletion and common single nucleotide polymorphisms (SNPs) appear to contribute independently to RBC phenotypes among AAs. In the 2p21 region, we identified a novel variant of PRKCE distinctly associated with Hct in AAs. In a genome-wide admixture mapping scan, local European ancestry at the 6p22 region containing HFE and LRRC16A was associated with higher Hgb. LRRC16A has been previously associated with the platelet count and mean platelet volume in AAs, but not with Hgb. Finally, we extended to AAs the findings of association of erythrocyte traits with several loci previously reported in Europeans and/or Asians, including CD164 and HBS1L-MYB. In summary, this large-scale genome-wide analysis in AAs has extended the importance of several RBC-associated genetic loci to AAs and identified allelic heterogeneity and pleiotropy at several previously known genetic loci associated with blood cell traits in AAs.
Human molecular genetics.Hum Mol Genet.2013 Jun 15;22(12):2529-38. doi: 10.1093/hmg/ddt087. Epub 2013 Feb 26.
Laboratory red blood cell (RBC) measurements are clinically important, heritable and differ among ethnic groups. To identify genetic variants that contribute to RBC phenotypes in African Americans (AAs), we conducted a genome-wide association study in up to ∼16 500 AAs. The alpha-globin locus on c
PMID 23446634

The importance of laboratory parameters in patients with obstructive sleep apnea syndrome.

Kurt OK, Yildiz N.SourceaDepartment of Chest Diseases bDepartment of Neurology, Abant Izzet Baysal University Faculty of Medicine, Bolu, Turkey.
Blood coagulation & fibrinolysis : an international journal in haemostasis and thrombosis.Blood Coagul Fibrinolysis.2013 Jun;24(4):371-4. doi: 10.1097/MBC.0b013e32835d53d4.
Platelet activation and inflammation are the related mechanisms of pathogenesis in obstructive sleep apnea syndrome (OSAS). Mean platelet volume (MPV) and platelet distribution width (PDW) are the markers of platelet activation. C-reactive protein (CRP) and red cell distribution width (RDW) in relat
PMID 23322273

Renal function is independently associated with red cell distribution width in kidney transplant recipients: a potential new auxiliary parameter for the clinical evaluation of patients with chronic kidney disease.

Ujszaszi A, Molnar MZ, Czira ME, Novak M, Mucsi I.SourceInstitute of Pathophysiology, Semmelweis University, Budapest, Hungary; Harold Simmons Center for Chronic Disease Research & Epidemiology, University of California Irvine Medical Center, Irvine, CA, USA.
British journal of haematology.Br J Haematol.2013 Jun;161(5):715-25. doi: 10.1111/bjh.12315. Epub 2013 Mar 27.
Red cell distribution width (RDW), a measure of heterogeneity in the size of circulating erythrocytes, reportedly predicts mortality. Similarly to RDW, impaired renal function is also associated with inflammation and protein-energy wasting. This study assessed if renal function is associated with RD
PMID 23530521

Japanese Journal

Red Blood Cell Distribution Width Is Longitudinally Associated With Mortality and Anemia in Heart Failure Patients

Nunez Julio,Nunez Eduardo,Rizopoulos Dimitris [他]
Circulation journal : official journal of the Japanese Circulation Society 78(2), 410-418, 2014-02
NAID 40019950893

Red Blood Cell Distribution Width Is Longitudinally Associated With Mortality and Anemia in Heart Failure Patients

Núñez Julio,Núñez Eduardo,Rizopoulos Dimitris,Miñana Gema,Bodí Vicent,Bondanza Lourdes,Husser Oliver,Merlos Pilar,Santas Enrique,Pascual-Figal Domingo,Chorro Francisco J.,Sanchis Juan
Circulation Journal 78(2), 410-418, 2014
… Background: Red blood cell distribution width (RDW) has been found to be an independent predictor for adverse outcome in patients with heart failure (HF), but there are no data on the association of longitudinal RDW with all-cause mortality and occurrence of anemia. …
NAID 130003382222

Impact of Red Blood Cell Distribution Width on Long-Term Mortality in Diabetic Patients After Percutaneous Coronary Intervention

TSUBOI Shuta,MIYAUCHI Katsumi,KASAI Takatoshi,OGITA Manabu,DOHI Tomotaka,MIYAZAKI Tadashi,YOKOYAMA Takayuki,KOJIMA Takahiko,YOKOYAMA Ken,KURATA Takeshi,DAIDA Hiroyuki
Circulation journal : official journal of the Japanese Circulation Society 77(2), 456-461, 2013-01-25
NAID 10031138925