Hi Jeff! I keep infections of either a UTI or Respratory Infection. had an IGG test done last December but that test by what I thought was testing my for food allergies. It was a diagnostic tool for testing Celiac Sprue and check for food allergies. But am not sure what other things they use this test for. A really simple blood test. Wished I knew more about it except for what I learned. Good luck! Getting infections all the time are aggrivating. Fightng a respiratory one at the present that does not want to shake itself off. Hope you find out what happens getting the test!