Studies on Platelet in Mucocutaneous Lymphnode Syndrome (MCLS)

—Platelet Function—

Abstract

The studies on platelets of 75 cases with MCLS were carried out, and the results were summarized as follows.
(1) Patients with abnormally high platelet count of more than 52.3×10⁴/cmm (M±SD) were observed in 17.3% of the cases at their first visit to our hospital, and in 86.7% during the later courses. Platelet count more than 75×10⁴/cmm was found in 1.3% of the first visit and in 37.3% during the later courses. In most cases marked thrombocytosis was observed between the 9th to 29th day after the onset, and recovered to normal level after 30 days. The average peak of thrombocytosis was on the 13th day. The platelet count in a group of the patients under one year old showed rather high value as compared with that in a group of the patients more than one year old.
(2) Platelet retention rate appeared normal.
(3) Platelet aggregation test using ADP, adrenalin, collagen, and ristocetin as aggregation inducers revealed hyperaggregability. This was often expected to occur in patients under one year old.
(4) Almost 70% of the cases examined at the first visit revealed high β-thromboglobulin level in thier plasma. All the patients under one year old showed high β-thromboglobulin level, but normal level more than 3 years. High β-thromboglobulin level was frequently found during the first month of the disease and it tended to decrease gradually thereafter.
(5) Platelet life span was measured in one case and the prolongation of life span was noticed.
These data suggested that the platelet function in the cases with MCLS was in the state of hyperfunction. The thrombocytosis found in this disease was suggested due to the increased platelet production or/and the decreased platelet destruction.