Keratoconus and atopic diseases.

In a survey of 162 keratoconus patients, we set out to investigate individual conditions, such as asthma, hay fever, connective tissue syndromes, and eye rubbing, and to determine their relationship of keratoconus. It was found that the prevalence of asthma rises from 0.4% to 1% in the control group to 17.9% in the keratoconus group, or an eighteenfold increase. In addition, the incidence of hay fever in keratoconus patients was found to be 35.7%. As multifactorial disorders, keratoconus and asthma may share some of the multiple genes necessary for the expression of the disorder. Previous findings of excessive eye rubbing in keratoconus patients were confirmed in this study. Finally, we found that the incidence of connective tissue disorders associated with keratoconus was negligible.