Sometimes it’s zebras

The TV doctor Gregory House would often say, when you hear hooves outside your window, you should expect to see horses, not zebras. The point is a good one, but can mean that a rare diagnosis is overlooked. And it ignores context - that is, where you window is located. For example, in a case known to us, a Jewish man in New Jersey was diagnosed with rheumatoid arthritis (RA) by an immunologist. The immunologist remarked at the time that if he’d been a patient in Wyoming, it’s unlikely the same diagnosis would have been reached, but the immunologist, familiar with Jewish genetic disorders, thought RA as a likely possibility from the outset. An immunologist in Wyoming would probably not have thought so, thinking horses not zebras..

CANVAS is sufficiently rare that the average doctor would be unlikely to encounter a single case in the lifetime of their practice. But if the word is spread, then when a patient does present with symptoms that match CANVAS, the doctor may at least consider the possibility that indeed their patient has CANVAS or other RFC1 condition..