In a study funded by a grant from the National Rosacea Society (NRS), researchers may have uncovered clues that may lead to a diagnostic marker for subtype 4 (ocular) rosacea, a chronic condition that may have severe consequences if left untreated -- including reduced vision. In publishing the final study results in the medical Journal of Proteome Research,1 the researchers noted that ocular rosacea often may be difficult to diagnose, especially in the absence of signs of rosacea on the skin. In addition, it may be frequently overlooked by non-eye doctors.
"Ocular rosacea is potentially a vision-threatening condition that may be easily missed," said Dr. Mark Mannis, chairman of ophthalmology at the University of California, Davis and one of the study's investigators. "We are excited that our study may ultimately lead to the first diagnostic test that could alert physicians to eye involvement before it grows more serious."
Samples of tears from 16 ocular rosacea patients and 21 individuals without rosacea were collected by Dr. Mannis and colleagues and were analyzed for the presence of oligosaccharides, a type of carbohydrate that may be found in the mucus component of the tear fluid. Oligosaccharides are known to be sensitive to the biochemical environment and could be an indicator of disease states.
The researchers found that the presence of high levels of oligosaccharides may be a diagnostic indication of ocular rosacea and that high levels of 13 particular types of the compound were associated with rosacea and may serve as more specific markers for the disorder. Since a general increase of oligosaccharides may not necessarily be specific to rosacea, they emphasized that the types of oligosaccharides found in greatest abundance in rosacea patients should be evaluated in further research for their specificity as markers for ocular rosacea.
Ocular rosacea may be present in varying degrees in up to 50 percent of rosacea sufferers. In an NRS survey of 1,780 rosacea patients reporting ocular symptoms, only 27 percent said they had been diagnosed with the condition, possibly indicating underdiagnosis. Typical symptoms of ocular rosacea may include a watery or bloodshot appearance, foreign body sensation, burning or stinging, itching, light sensitivity, blurred vision, and visible blood vessels or redness of the eyelid. A history of styes and feeling of dryness in the eyes are also key indicators.
"We plan to further investigate which types of oligosaccharides are the best indicators of rosacea in order to achieve even greater accuracy in distinguishing ocular rosacea from normal patients," Dr. Mannis said.
- An HJ, Ninonuevo M, Aguilan J, Liu H, Lebrilla CB, Alvarenga LS, Mannis MJ. Glycomics analyses of tear fluid for the diagnostic detection of ocular rosacea. Journal of Proteome Research. 2005;4:1981-1987