Storage Pool Disease of Platelets in an Infant with Thrombocytopenic Absent Radii Syndrome Simulating Fanconi Anemia

Abstract

This study reports the first example of storage pool disease, “aspirin like” variety, in a 4 month old infant with multiple congenital malformations including bilateral absent radii, thumbs and right kidney, dislocation of hip joints, equinovarus, convergent squint and hypospadias. Platelet count was decreased to 29,000/mm3 at birth and rose to 296,000/mm3 4 months later. Studies of platelet function showed a slightly prolonged bleeding time (ivy technic), decreased aggregation to collagen 0,003% and ADP 4 MM, total absence of aggregation to l-epinephrine and decreased platelet factor 4 activity. Platelet serotonin content was slightly decreased. These abnormal findings were equally detected with the father’s platelets, suggesting a genetic transmission of the platelet disorder. Platelet function of the mother, which is a first cousin of her husband, were normal. This study provides further evidence to the hereditary nature of thrombocytopenic absent radii (TAR) syndrome. The impaired platelet function seems to be an important and helpful test in the differential diagnosis of TAR syndrome and Fanconi anemia.

Congenital Disorders Affecting Platelets

“…A platelet storage pool defect has also been described in the TAR syn drome [66,249,303]. Unfortunately, none of these reports have included electron micrographs of the platelets.…”

“…Circulating platelets are decreased in number, but appear to function and survive normally according to most reports [191,241]. Recently, several investi gators have reported a platelet storage pool defect in this syndrome [66,249,303], unfortunately, none of these reports have included ultrastructural observations.…”