Because the symptoms are so varied and different in most patients.
Ohhhhhh....it took a long while to figure out what my ex wife had....I think she exhibited symptoms for some 3 or 4 years before she was diagnosed.
But the rash on the face, which to doctors is a dead giveaway of the disease, doesn't appear on a lot of people.....my ex never had the rash, mainly she had VERY sore joints...all joints were affected, from toes all the way up to the fingers. Some days, she couldn't pick up a pen to write......so the doctors thought she had arthritis for a very long time. And all the time this was happening, her very own anti-bodies were munching away at her kidneys and liver......no one knew.
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