Intravascular platelet activation in the hemolytic uremic syndrome
M D Walters1, M Levin, C Smith
1Department of Paediatric Nephrology, Hospital for Sick Children, London, United Kingdom.
Kidney International
|January 1, 1988
Summary
Intravascular platelet activation occurs in both typical and atypical hemolytic uremic syndrome (HUS). Different mechanisms may initiate platelet activation in these HUS subgroups, with abnormal PGI2 synthesis noted in atypical HUS.
Area of Science:
- Hematology
- Nephrology
- Pathophysiology
Background:
- Hemolytic uremic syndrome (HUS) is a thrombotic microangiopathy.
- Distinguishing between typical (epidemic) and atypical (sporadic) HUS is crucial for understanding disease mechanisms.
Purpose of the Study:
- To investigate intravascular platelet activation in typical and atypical HUS.
- To identify differences in platelet behavior and associated factors between HUS subtypes.
Main Methods:
- Assessed platelet aggregation and serotonin levels in HUS patients.
- Measured endothelial prostacyclin (PGI2) production.
- Evaluated plasma-induced platelet aggregation and serum platelet aggregating activity.
Main Results:
- Both HUS types showed defective platelet aggregation, decreased platelet serotonin, and increased plasma serotonin.
- Reduced PGI2 production was more frequent in atypical HUS.
- Plasma from HUS patients induced platelet aggregation, but this was not linked to thrombocytopenia or disease stage.
- Atypical HUS patients had higher serum platelet aggregating activity.
Conclusions:
- Intravascular platelet activation is a common feature in both typical and atypical HUS.
- Distinct mechanisms may underlie platelet activation in typical and atypical HUS.
- Abnormal PGI2 synthesis is implicated in atypical HUS, while mechanisms for typical HUS remain less clear.
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