Back before antibiotics, they used to call syphilis "The Great Imitator." The disease, caused by a spiral-shaped bacteria known as a spirochete, could cause so many different kinds of problems it seemed like 10 diseases in one.

Genetically, Lyme Disease is very close to syphilis. It's also a spirochete, and it is the new "Great Imitator." (1) The main difficult thing about Lyme Disease is that the tests for it currently are not that good. There are a lot of false positives / negatives, and there is no test that show whether a patient has been cured, only whether they've ever been infected.

Neurological Lyme aka neuroborreliosis can cause a number of neurological / psychiatric symptoms, including symptoms like OCD. Doctors never check for Lyme when a patient presents with sudden onset psych problems, even though it's a known cause.

TL;DR -- If you're having mysterious health problems, add a Lyme test to your other tests.

(1) interesting side note -- there are some studies that suggest it can also be sexually transmitting and/or transmitted from mother to child