short report: Bleeding disorders in Lowe syndrome patients: evidence for a link between OCRL mutations and primary haemostasis disorders

Lowe syndrome (LS) is a rare X‐linked disorder caused by mutations in the oculocerebrorenal gene (OCRL), encoding OCRL, a phosphatidylinositol 5–phosphatase with a RhoGAP domain. An abnormal rate of haemorrhagic events was found in a retrospective clinical survey. Herein, we report the results of exploration of haemostasis in six LS patients. All patients had normal coagulation tests but prolonged closure times (CTs) in the PFA–100 system. Healthy donors’ blood samples incubated with a RhoA kinase inhibitor had prolonged CTs. This suggests that an aberrant RhoA pathway in platelets contributes to CT prolongation and primary haemostasis disorders in LS.