The National Institutes of Health defines a rare disease as one that affects fewer than 200,000 persons in the US. But is every rare disease truly rare? Consider Sydney's experience: in 2003, she visited her doctor complaining of dry mouth, a symptom often associated with aging. Following the conventional medical wisdom of “looking for horses, not zebras,” the doctor assumed it was dehydration and advised her to increase her water intake.
Unfortunately, this advice exacerbated her condition. Ten years later, after enduring persistent symptoms and dental issues, she finally received a diagnosis of Sjogren's disease (the symptoms of which include dry mouth). The advice from her doctor years earlier caused more harm than good because drinking more water washed away what little saliva she had and led to tooth decay. Sydney's story is sadly typical of many autoimmune disease patients.
Many patients struggle with a diagnosis because their diseases are believed to be rare and doctors often look for "horses" and dismiss the possibility of "zebras." A 2010 paper by Eaton shows the prevalence of Sjogren’s to be about 200,000 in the US. Still rare, but 6 times the estimate of an earlier study, which put Sjogren's in the ultra rare category. Some might conclude that this is evidence of the common belief that autoimmune disease is increasing, but more likely patients like Sydney who had the disease from 10 years earlier were simply undiagnosed. The disease was rare because it was believed to be rare, so physicians rarely diagnosed it in a loop that perpetuated the rareness and difficulty of diagnosis.
With 156 suspected and confirmed autoimmune diseases in the Autoimmune Registry,121 of these are currently believed to qualify under the NIH definition of “rare.” But misdiagnoses and underdiagnoses are rampant and Sydney’s story is only one of many. On today's Rare Disease Day, let's raise awareness of these "rare" diseases so that there can be better and more timely diagnoses and patients do not continue to suffer needlessly. Help us spread the word about your "rare" autoimmune disease by sharing your story with the hashtags #rareautoimmunedisease and #rareautoimmuneawareness. You can make a video here or contact us to feature your story on our diagnostic journeys page.
To support the Autoimmune Registry, please join our registry or share it with a friend who has an autoimmune condition. Donations are also greatly appreciated!
