a series of infection agents can cause chronic lower back pain.
most people will think they are getting old, that they have been sitting incorecctly, lifting incorectly.
I myself got lower back pain sneaking up on me some time back, I had it for a year. Then I tried to treat something else with a special Antibiotic and the back pain and several other things went away.
The problem with Antibiotics is many Antibiotics have side effects, and if you do not know what infection it is you can end up taking a series of non effective Antibiotics that only weakens you. On the other hand the right antibiotics can do miracles.