Free sialic acid storage (Salla) disease in Sweden.

The first 23 patients diagnosed with Salla disease in Sweden are presented. A high incidence of the "Finnish" R39C mutation, together with genealogical data, indicates that a large proportion of the mutations are of Finnish origin. All patients had pathologically high levels of free sialic acid in urine and in fibroblasts. The clinical picture confirms what has already been reported from Finland, with early psychomotor retardation, ataxia and speech problems. One-third of the patients had epilepsy.

CONCLUSIONS

Salla disease is more common in Sweden than supposed. A large proportion of the mutated alleles seem to be of Finnish origin. The clinical picture is the same as that reported from Finland.