I've seen about every doctor possible and finally got a diagnosis of Mast Cell Activation Syndrome (MCAS). The doctor said many of his patients suffer from mold. He recommended a whole home mold inspection.
The inspector only discovered mold in the air handler itself, which isn't too uncommon. We could have just cleaned the handler coils but decided to pull the entire thing just to be sure. Only after it was pulled did we see about a 15 foot long stretch of mold going directly into our ductwork.
In the bedroom we were replacing our carpet with hardwood floors and discovered a 10 foot mold stretch behind the baseboards.
Mold is being remediated in my house as I type this. My wife and I have been dealing with insidious symptoms for years (brain fog, joint pain, anxiety, muscle stiffness, balance issues, neuropathy, increased ADHD, and more). Only recently did we discover that there was black mold (Stachybotrys chartarum) in both our bedroom and in the air supply trunk located after the air handler. The bedroom mold was caused by an inactive leak that must have been there before we ever bought the house. The air handler was due to poor installation alongside high humidity.
We’ve already noticed a huge decrease in symptoms about 10 days after the air handler was pulled.