I had my suspicions about a place I worked for 6 months.
Over my time working there I lost feeling in my hands, feet and then my arms and legs. Went through a full barrage of tests and feared the worst as the tests got more and more serious. Nerve conduction tests showed real problems with my nerves in most areas.
My liver test results were at levels the docs hadn’t seen before – it looked like I was drinking 5-10 bottles of spirits a day.
I left that job, and everything came back to normal in 2 months. I later found out the building had been badly flooded a while before I started and some later blood tests showed a bacterial infection had caused all my problems.