Mean corpuscular volume 593419 224098481 2008-07-07T08:36:46Z 219.78.170.111 The '''mean corpuscular volume''', or '''MCV''', is a measure of the average [[red blood cell]] volume (i.e. size) that is reported as part of a standard [[complete blood count]]. In patients with [[anemia]], it is the MCV measurement that allows classification as either a [[microcytic anemia]] (MCV below normal range) or [[macrocytic anemia]] (MCV above normal range). It can be calculated (in litres) by dividing the [[hematocrit]] by the [[complete blood count|red blood cell count]] (number of red blood cells per litre). The result is typically reported in femtolitres. If the MCV was determined by automated equipment, the result can be compared to RBC morphology on a [[peripheral blood smear]]. Any deviation would be indicative of either faulty equipment or technician error. The normal [[reference range]] is typically 80-100 [[1 E-18 m³|fL]]<ref>[http://www.nlm.nih.gov/medlineplus/ency/article/003648.htm MedlinePlus Medical Encyclopedia: RBC indices]</ref>. In presence of hemolytic anaemia, presence of reticulocytes can increase MCV. In [[pernicious anemia]] (macrocytic), MCV can range up to 150 femtolitres. An elevated MCV is also associated with [[alcoholism]]<ref>{{cite journal | author = Tønnesen H, Hejberg L, Frobenius S, Andersen J | title = Erythrocyte mean cell volume--correlation to drinking pattern in heavy alcoholics | journal = Acta Med Scand | volume = 219 | issue = 5 | pages = 515–8 | year = 1986 | pmid = 3739755}}</ref> (as are an elevated [[Gamma glutamyl transpeptidase|GGT]] and a ratio of [[Aspartate transaminase|AST]]:[[Alanine transaminase|ALT]] of 2:1). [[Vitamin B12]] deficiency has also been associated with macrocytic anemia (high MCV numbers). The most common causes of [[microcytic anemia]] are iron deficiency (due to inadequate dietary intake, gastrointestinal blood loss, or menstrual blood loss), thalassemia, or chronic disease. A low MCV number in a patient with a positive [[stool guaiac test]] (bloody stool) is highly suggestive of GI cancer. In [[iron deficiency anemia]] (microcytic anemia), it can be as low as 60 to 70 femtolitres. In cases of [[thalassemia]], the MCV may be low even though the patient is not iron deficient. ==References== <references/> ==See also== *[[Anemia#Differential_diagnosis|Anemia: Differential Diagnosis]] *[[Liver function tests]] *[[Full blood count]] *[[Red blood cell indices]] **[[Mean corpuscular hemoglobin]] **[[Mean corpuscular hemoglobin concentration]] [[Category:Blood tests]] [[fr:Volume globulaire moyen]] [[ja:平均赤血球容積]] [[pl:MCV]] [[pt:Volume corpuscular médio]]