Tuberous sclerosis in Western Sweden. A population study of cases with early childhood onset.

OBJECTIVE

To study the prevalence of tuberous sclerosis in children and adolescents.

DESIGN

Previously published diagnostic criteria for tuberous sclerosis were used. All physicians likely to encounter young patients with tuberous sclerosis were contacted by way of a screening questionnaire.

SETTING

The study was performed in a circumscribed geographic area (western Sweden).

PATIENTS AND OTHER PARTICIPANTS

The sample was population based. However, only patients with such severe and early symptoms that referral to a physician had been considered necessary and relatives of these patients with tuberous sclerosis could be included. This was because there is currently no diagnostic marker for tuberous sclerosis that could be used as a screening tool.

RESULTS

The peak prevalence (one in 6800 individuals) for tuberous sclerosis was found in the 11- to 15-year-old age group. For the whole age cohort, 0 to 20 years, the prevalence was one in 12,900 individuals.

CONCLUSIONS

The prevalence for the school-age group was the highest ever reported in the literature on tuberous sclerosis. However, it is likely that the true prevalence of tuberous sclerosis in the general population is even higher.