Page 262 - Haematologica Atlas of Hematologic Cytology

Figure 1 1 1 Platelet Platelet macrocytosis Platelets are are moderately enlarged in in immune thrombocytopenia
(ITP) (Noris et et et et et et al al al al 2014) with with a
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mean platelet platelet diameter of of 3 3 1 1 1 1 m m m m m m m m m m compared with with 2 2 5 5 m m m m m m m m m m in in in healthy healthy subjects subjects On average 16% of of platelets are are are larger than half a
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red red red red cell (3 5% in in healthy healthy subjects) En- larged platelet platelet platelet platelet size is shared by by the the other acquired thrombocytopenias thrombocytopenias due to to to accelerated platelet platelet platelet platelet turnover as as as as well as as as as by by many inherited thrombocytopenias thrombocytopenias Most platelets have a
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normal normal internal structure and and and no no no no abnormali es es es es of of red red cells and and and leukocytes are are present These ndings are are useful to to to to dis nguish ITP from inherited thromboytopenias and and and other forms of of acquired thrombocytopenias AB
Figure 2 Platelet anisocytosis As in in many inherited thrombocytopenias and other forms of consump on on throm- bocytopenia
platelet platelet size is is quite variable in each ITP pa ent (A) and both platelet platelet distribu on width (calculated by by electronic counters) and platelet diameter distribu on on on width (measured by by microscopy examina on on on of periphe- ral blood lms) are larger than controls Average platelet diameter distribu on on width is is 3 3 5 mm mm (2 3 3 mm mm in healthy subjects) but in a
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few cases (B) this parameter as as as well as as as platelet diameter are similar to those of healthy subjects subjects (Noris et et al 2014) Thus mild platelet macrocytosis and anisocytosis support the the diagnosis of ITP but their absence does not exclude this condi on on 249