Swelling in hands & feet

My daughter has been having severe swelling in her hands and fingers (to the extent she can't wear her wedding rings) and in her feet. Her feet are so swollen that you can't see the ankle bones on the sides. This began after she returned from a trip to Mexico (in January) and has been ongoing since then. She's seen a rheumatologist, cardiologist, and her family doctor but no one seems to be able to definitively diagnose the problem! They think it could be Rheumatoid Arthritis or something called Chikengunya (?).

I'm wondering if anyone else has ever experienced these symptoms and what the diagnosis is?

She's in her early 40's; has been to Mexico every January for the past 20 years; and her hands are so swollen they look like a fat claw. She can't bend her fingers!