[Autosomal dominant compelling helio-ophthalmic outburst syndrome (photic sneeze reflex). Clinical study of six Spanish families].

Introduction: Sneeze is an ubiquitous phenomenon that happens to everyone. In spite of this, little attention has been paid to it, among medical literature in general, and even less in neurologic texts. A curious entity, called autosomal dominant compelling helio-ophthalmic outburst syndrome, has been scarcely described in the scientific literature. This reflex appears when subjects are exposed suddenly to intense sunlight and it consists of long incoercible sneeze bursts. There are no publications on this subject among the spanish literature.and intensity increase with time.
Objective: To study the clinical and physiological features of the reflex in Spanish families.
Patients and Method: Affected subjects were identified by personal interview and given a questionnaire drawn up for this study. Besides, they were instructed to give the questionnaire to their relatives.and intensity increase with time.
Results: All the six families showed a high-penetrance, autosomal dominant inheritance. The reflex had a high consistency, a latency about 3 seconds, an intersneeze interval of 2 seconds and a frequency of 2-3 sneezes/ burst. Refractory period was long.and intensity increase with time.
Discussion: Our study suggest a higher consistency, shorter latency and lower age of onset of the reflex in our patients than general population, and that frequency and intensity increase with time.