Immunoglobulin G-361, A-76, M-28 What do these low levels mean?

Dont worry but first. thing I would be wondering is why did you have those tests done? Are you having recurrent infections?(not just "regular colds"?),,,but if you were my pt.first thing I would do is repeat the tests to confirm results..If you are having recurrent sinus infections, bronchitis, etc & the repeat tests are similar, next step would be see an allergist/immunologist to further evaluate. Good luck.
These are. types of antibodies from a test called serum electrophoresis. Here's a good link: http://www.webmd.com/a-to-z-guides/immunoglobulins.