The PFA-100 ® does not predict delta-granule platelet storage pool deficiencies.
There are no published reports investigating the ability of the platelet function analyzer (PFA-100(®) ) to detect the presence of delta-granule platelet storage pool deficiencies (δ-PSPD), a common mild bleeding disorder. Prior studies of the PFA-100(®) and congenital platelet disorders have been limited by small numbers of patients with a variety of disorders. We examined PFA-100(®) results in a large paediatric patient population diagnosed specifically with δ-PSPD, and determined the relationship between PFA-100(®) and platelet electron microscopy (the gold standard for diagnosis). This study is a retrospective review of patients <19 years of age diagnosed with δ-PSPD at Nationwide Children's Hospital from 2008 to 2010. To examine the correlation between PFA-100(®) and average number of granules per platelet we used Spearman's Rho as a non-parametric measure of dependence. A total of 105 patients diagnosed with δ-PSPD were included, of which 99 patients underwent PFA-100(®) testing. Of those tested 46% had at least one abnormal closure time, whereas 16% had abnormal results for both cartridges. We found no statistical correlation between C-EPI closure time and average number of granules per platelet (ρ= -0.0095, P-value = 0.9328), nor between C-ADP closure time and the average number of granules (ρ = 0.0315, P-value = 0.7798). The PFA-100(®), a widely used screening test for suspected bleeding disorders, did not correlate with presence or severity of δ-PSPD as determined by platelet electron microscopy. When evaluating patients with suspected bleeding disorders, PFA-100(®) alone cannot be used to rule out the presence of a δ-PSPD.
College of Medicine, The Ohio State University, Columbus, OH, USA.
J L
JL
Sladky
J
J
Klima
L
L
Grooms
B A
BA
Kerlin
S H
SH
O'Brien
D000293:Adolescent; D001791:Blood Platelet Disorders / Q000097:blood / Q000175:diagnosis*; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D010979:Platelet Function Tests / Q000295:instrumentation* / Q000592:standards; D011237:Predictive Value of Tests; D012189:Retrospective Studies