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Published on: December 27, 2017
Platelet refractoriness to classical agonists in a child with essential thrombocythemia
Jose Carlos Jaime-Perez1, David Gomez-Almaguer
1Autonomous University of Nuevo Leon, Monterrey, Mexico. carjaime@hotmail.com
Background:
Essential thrombocythemia is a rare disease during childhood. Platelet morphological abnormalities are frequent and defects in platelet function tests, mainly hypoaggregation, occur.
Materials And Methods:
An incidental diagnosis of essential thrombocythemia was established in a 9-year-old boy with a platelet count of 2050 x 10(9)/l. His platelets were studied for aggregation defects with four classical agonists employing optical aggregometry.
Results:
Aggregation ranged from 5% for adrenaline, 8% for collagen, 12% for ristocetin, to 25% with adenosine diphosphate, followed by complete disaggregation.
Conclusion:
Platelet refractoriness to classical agonists, probably compounded by platelet GPIb deficiency, was documented. The differential diagnosis is discussed.
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