BACKGROUND: Platelet function disorders are a fairly common cause of bleeding manifestations. Although their relative types and incidence are well documented, data from India are lacking. METHODS: Between 1970 and 1991, we studied the clinical and laboratory features of 144 north Indian patients who presented to our hospital with a bleeding diathesis in whom coagulation disorders, von Willebrand's disease and a history of drug ingestion were absent. RESULTS: Isolated platelet factor 3 availability defect was the commonest (56 cases) followed by the thrombasthenias (49 cases), arachidonic acid pathway defect (26 cases), storage pool disease (8 cases) and the Bernard-Soulier syndrome (3 cases). Isolated platelet factor 3 deficiency was rare (2 cases). Two varieties of thrombasthenia were seen--the classical Glanzmann's (13 cases) and thrombopathic (36 cases). The latter was characterized by absent or sub-normal platelet aggregation with agonists along with a reduced (to less than 50% of normal) total platelet factor 3 content. This has not been reported from western countries. Patients with classical Glanzmann's thrombopathic thrombasthenia with absent platelet aggregation and isolated platelet factor 3 deficiency were severe bleeders. Their family history suggested an autosomal recessive transmission in Glanzmann's and thrombopathic thrombasthenia and a possible autosomal dominant transmission in isolated platelet factor 3 availability defect and isolated platelet factor 3 deficiency. CONCLUSION: The frequency of various types of platelet function disorders in Indians is similar to that in western populations except that the incidence of thrombopathic thrombasthenias is higher in India.
BACKGROUND:Platelet function disorders are a fairly common cause of bleeding manifestations. Although their relative types and incidence are well documented, data from India are lacking. METHODS: Between 1970 and 1991, we studied the clinical and laboratory features of 144 north Indian patients who presented to our hospital with a bleeding diathesis in whom coagulation disorders, von Willebrand's disease and a history of drug ingestion were absent. RESULTS: Isolated platelet factor 3 availability defect was the commonest (56 cases) followed by the thrombasthenias (49 cases), arachidonic acid pathway defect (26 cases), storage pool disease (8 cases) and the Bernard-Soulier syndrome (3 cases). Isolated platelet factor 3 deficiency was rare (2 cases). Two varieties of thrombasthenia were seen--the classical Glanzmann's (13 cases) and thrombopathic (36 cases). The latter was characterized by absent or sub-normal platelet aggregation with agonists along with a reduced (to less than 50% of normal) total platelet factor 3 content. This has not been reported from western countries. Patients with classical Glanzmann's thrombopathic thrombasthenia with absent platelet aggregation and isolated platelet factor 3 deficiency were severe bleeders. Their family history suggested an autosomal recessive transmission in Glanzmann's and thrombopathic thrombasthenia and a possible autosomal dominant transmission in isolated platelet factor 3 availability defect and isolated platelet factor 3 deficiency. CONCLUSION: The frequency of various types of platelet function disorders in Indians is similar to that in western populations except that the incidence of thrombopathic thrombasthenias is higher in India.