Need some new avenues to explore.

I had abdominoplasty a little over 2 years ago.  I have been plagued with bacterial or other infections that can never be diagnosed.  I have had 4 clean out surgeries complete with many samples taken and sent to the lab.  The results always come back indicating no infection.  I have seen an Infectious Disease doctor for over 8 months.  My surgeon just shakes his head and claims he has no explanation as to why this continues to happen.  Just this past week an area on my abdomen again turn red, swollen and looked like a pimple coming to a head which was very painful.  My general MD took a sample (which was  ugly puss) and stated that there was no way the test results would come back without indicating infection.  They came back NO INFECTION.  I now have an area on the original scar that is starting to turn red.  I do not feel the Infection Doctor or more surgery is going to solve the situation.  I lost  my job a year ago and have no insurance.  Does anyone have any suggestions or had the same experience.  I've also had a cat scan.