Mechanisms of hemostasis in primary thrombocythemia have still remained unknown. A case with primary thrombocythemia was reported, in whom abnormalities of platelet function were found and thrombokinetics as well as ultrastructural study were performed. From these results, some suggestive data concerning abnormalities of hemostasis were obtained.
Case: Male 62 Yrs. A company employee.
Chief complaints: Bleeding tendency after shaving, easy fatiguability and epigastralgia.
Onset and course of present illness: Leukocytosis was pointed out by medical examination on April 8, 1977.
Admission of present state: There were hepatomegaly (1 finger breath) but no purpura, no lymphadenopathy and no splenomegaly.
Hematological examinations: RBC 548×104/μl, Hb 15.8g/dl, Ht 50%, Ret 7‰, Plt 80.4-162×104/μl, WBC 13, 700/μl.
Neutrophil alkaline phosphatase activity: Rate 100%, score 380. Platelets showed morphologically anisocytosis, aggregated formation and large size over 3.5μ in diameter, and moreover they had a few specific granules, great and small sized mitochondriae and swollen cristae and so on in electron-microscopic level.
Examinations on coagulofibrinolysis: Caolin activated PTT was subnormal. PTT and recalcification clotting time were prolonged slightly. Rumpel-Reede's phenomenon was strongly positive and bleeding time prolonged incidentally to 8.5 minutes. There is no abnormality in fibrinolysis.
Platelet function: Retention rate; 12-24%. Aggregation; No pathological finding but abnormal aggregation curve with ADP (2μM) was observed. In PRP (160×104/μl near native platelet level), secondary aggregation curve and accelerated aggregation were realized. Platelet factor 3 content and platelet availability test were within normal limit. In thrombokinetic study by using 51Cr labeled platelet, the survival time t 1/2 and t 10% were 3.5 days and 8 days, respectively.
Comments: From above-mentioned characteristic results, his diagnosis was comformed as primary thrombocythemia. It might be suggested that a possibility of intravascular thromboembolic formation would be indicated as one of more important factors, though bleeding tendency in primary thrombocythemia were complicatedly associated with some detects in coagulation, disturbed platelet functions and abnormal morphological features in light-and electron-microscopic levels.