Stormorken syndrome or York platelet syndrome: A clinician's dilemma.

To the Editor:

We read the paper recently published by Markello et al. in the latest issue [1]. Analysis of our observations [2] together with a review of other cases [3], [4] suggests that patients with the c.910C>T mutation in STIM1 gene (p.R304W) have the same heterogeneous disease and that Stormorken syndrome (StS) and York platelet syndrome (YPS) are probably two different names for the same clinical condition. The confusion could be due to the strategy used to study platelets. Indeed, in patients affected with YPS platelets have been extensively studied by electron microscopy, not in the patients with StS. It should be noted that among the many biological symptoms of StS, thrombocytopenia and thrombocytopathia have been first described as major and constant defects [2], [3], [4], [5].

Patients of families C and D carry the typical c.910C>T mutation also observed in StS. But the occurrence of miosis and the spleen anomalies have not been reported. Conversely, patients of families A and B bearing a different mutation (c.343A>T) located in EF-hand domain, do exhibit miosis and spleen anomalies. One YPS patient has been diagnosed for tubular aggregate myopathy (TAM). Muscle complaints and histopathological results found in YPS patients are identical to those observed in isolated TAM and StS patients. This suggests that other patients with TAM due to mutation of EF-hands could have other symptoms belonging to StS spectrum [6], [7]. The rimmed vacuoles observed in another YPS patient resemble tubular aggregates and require further investigations.

Based on the similar mutations and identical clinical phenotype, we suggest renaming these clinical conditions as the Stormorken–York platelet syndrome. Identifying the underlying genetic cause including heterogeneity in modifiers still remains a challenge.