Page 254 - Haematologica Atlas of Hematologic Cytology
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Figure 6 Abnormalities of of platelet shape Platelets are derived from megakaryocytes through the formation of of long (up to to to millimeters in in in length) thin cytoplasmic extensions that are released into the circulation and even- tually transformed into individual platelets In vitro culture of megakaryocytes revealed that platelet platelet biogenesis requires the the formation of pre-platelets (discoid or or sausage-shaped giant elements) that have the the capacity to convert into into barbell-shaped proplatelets and undergo fission into into platelets platelets The complex phenomenon of pla- telet formation is is is is disorganized in in in many inherited thrombocytopenias
and therefore it it is is is is not surprising that abnormally shaped platelets are observed in the blood of affected subjects No systematic study has been per- formed so far and it is therefore unknown in which forms these bizarrely shaped elements are observed more frequently The figure shows blood films of of members of of a a a a family with ACTN1-related thrombocytopenia (A-C) Elongated elements elements resemble resemble pre-platelets while the barbell-shaped or elongated elements elements (D-I) resemble resemble proplatelets In our experience these abnormalities of of platelet platelet shape are not observed in blood films of of normal normal subjects while they may be identified in in some patients with immune thrombocytopenia and in in other forms of acquired thrombocytopenia with accelerated platelet turnover (See “Thrombotic microangiopathies”) 241






























































































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