This document describes various red blood cell abnormalities and their associated disease states. It lists different types of abnormalities including anisocytosis, macrocytosis, microcytosis, poikilocytosis, spherocytosis, and drepanocytosis. Specific abnormalities are then defined such as burr cells, elliptocytes, and schistocytes. Each abnormality is paired with the disease states it is commonly associated with such as megaloblastic anemia for macrocytes and hereditary spherocytosis for spherocytes. Secondary abnormalities from membrane issues, trauma, abnormal hemoglobin, and distribution problems are also detailed.

1. ERYTHROCYTEABNORMALITIES AND ASSOCIATION WITH DISEASESTATES
RBC ABNORMALITY CELL DESCRIPTION ASSOCIATED DISEASE STATE
ANISOCYTOSIS Severe size variation Severe anemia(e.g.,megaloblastic,irondeficiency)
Macrocytes Large cells(>8um),MCV >100 fL
Megaloblasticanemia(B12 orfolate deficiency)
Liverdisease
Hemolyticanemia:increasedreticulocytes
Myeloma
Macrocytosis:newborns
Myelophthisicanemia
Oval macrocytes Large oval cells Megaloblasticanemia
Microcytes
Smallerthannormal cell (<6 um)
MCV <80 fL
Iron deficiencyanemia
Sideroblasticanemia
Thalassemia
Lead poisoning
POIKILOCYTOSIS Abnormal shape variation Severe anemia;certainsshapesare helpful diagnostically
SECONDARY TO MEMBRANE ABNORMALITIES:
Acanthocytes Small cell withfew,irregularlyspacedspicules of varyinglength
Microangiopathichemolyticanemia(MAHA)
Alcoholicliverdisease
Hereditaryacanthocytosis
Abetalipiproteinemia
Burr cells
RBCs withuniformlyspaced,pointedprojectionsontheirouter
edges.
Liverdisease
Uremia
Hemolyticanemia
Microangiopathichemolyticanemia(MAHA)
Thromboticthrombocytopenicpurpura(TTP)
Disseminatedintravascularcoagulation(DIC)
Carcinoma(stomach)
Pyruvate kinase deficiency
Codocytes
Hypochromiccell withcentral areaof hemoglobinpigment
Obstructive liverdisease
Hb SS, SC,S thalassemia
Thalassemia
Iron deficiency
Postsplenectomy
Echinocytes/ CrenatedRBC Equallyspaced,(10-30)shortbluntprojections Renal disease

2. ERYTHROCYTEABNORMALITIES AND ASSOCIATION WITH DISEASESTATES
RBC ABNORMALITY CELL DESCRIPTION ASSOCIATED DISEASE STATE
Elliptocytes/ Ovalocytes Oval or elliptical shapedcells
Hereditaryelliptocytosis
Iron deficiency
Megaloblasticanemia
Thalassemia
Myelophthisicanemia
Stomatocyte RBCs withslit-like areaof central pallor
Hereditarystomatocytosis
Obstructive liverdisease
Alcoholism,cirrhosis
Rhnull disease
Artifact
Spherocytes
Small,round,dense cellswithlackof central pallor;usually
microcytic
Hereditaryspherocytosis
DAT-positivehemolyticanemia
Otherhemolyticanemias(e.g.,Heinzbodyhemolyticanemia)
Aftertransfusion
Fragmentationhemolysis
SECONDARY TO TRAUMA:
Blistercells(marginal achromia) Raisedportionof membrane appearingfree of hemoglobin
Microangiopathichaemolyticanemia(MAHA)
Thromboticthrombocytopenicpurpura(TTP)
Hemolytic-uremicsyndrome (HUS)
Hb SS withpulmonaryemboli
Dacryocytes Cell withone pointedextremity(inshapeof drop)
Myelofibrosiswithmyeloidmetaplasia
Ineffective erythropoiesis
Myelophthisicanemia
Thalassemia
Megaloblasticanemia
Keratocytes Cell fragmentin shape of a helmet DIC, MAHA,TTP, HUS
Schistocytes/ Schizocytes Fragmentedcells,irregularlycontractedcells
DIC, MAHA,TTP, HUS
Uremia,carcinoma,severe burns
Heart valve hemolysis
March hemoglobinuria

3. ERYTHROCYTEABNORMALITIES AND ASSOCIATION WITH DISEASESTATES
RBC ABNORMALITY CELL DESCRIPTION ASSOCIATED DISEASE STATE
SECONDARY TO ABNORMAL HEMOGLOBIN:
Drepanocyte
RBCs inthe shape of a sickle orcrescentdue to the formationof
rod-like polymersof hemoglobinSwithinthe cell.
Sickle cell anemia
Hb SC disease,HbSβthalassemia
Hb O-Arab
ABNORMAL DISTRIBUTION
Rouleaux Redcellsappearas stacks of coinson the peripheral smear
Waldenstrom’smacroglobulinemia
Multiple myeloma
Chronicinflammatorydisorders
Some lymphomas
Agglutination Redcellsaggregate intorandomclustersormasses
Coldhemagglutinindisease
Paroxysmal nocturnal hemoglobinuria
Hemolyticanemias
Staphylococcal infections
Atypical pneumonia