Well, I'm no IFA expert by any stretch of the imagination, but I do know that the ELISA is considered an IFA:
"Indirect fluorescent-antibody (IFA) tests are used to demonstrate the presence of antibodies against a specific antigen in serum."
classes.midlandstech.edu/carterp/Courses/bio225/chap18/lecture5.htm"Enzyme linked immunosorbent assays (ELISA), also known as enzyme immunoassays (EIA), are tests designed to detect antigens or antibodies."
/www.dshs.state.tx.us/lab/serology_eia.shtmAnyway, the Equivocal result does mean that there was a reaction, but not one strong enough that the "powers that be" (CDC) want to admit that it's fully positive.
And you may very well have Bartonella as your top infection and once you start to treat that infection and have your bacterial load lower, then symptoms of other infections that you may have may begin to be more prominent. This is actually fairly common.
As Sarah said, this is worthy to at least be evaluated, but if I remember your symptoms well enough, you should likely be started on treatments with results like this.