Congenital adrenal hyperplasia due to 21-hydroxylase deficiency associated with bilateral keratoconus.

PURPOSE

To report a clinical association between congenital adrenal hyperplasia and keratoconus.

DESIGN

Observational case report.

METHODS

Two 25-year-old dizygotic female twins were retrospectively studied. Clinical history, hormonal serologic profile, complete ophthalmologic examination, and Holladay Diagnostic Summary variables were evaluated. In the course of a 15-month follow-up period, a progression of the corneal disease was observed.

RESULTS

In both twins a diagnosis of nonclassical congenital adrenal hyperplasia, due to 21-hydroxylase deficiency, was established when they were 21 years old. In one subject, the computed corneal topographic analyses diagnosed an asymmetric keratoconus in both eyes. A progressive form of fruste central keratoconus was also documented in her sister.

CONCLUSIONS

Congenital adrenal hyperplasia may be associated with keratoconus. An abnormal steroidogenic pathway, affecting the normal development of the cornea, could induce stromal abnormalities that lead to corneal ectasia.