What does an elevated gloublin of 4.2 mean?? (normal range is 2.0-4.0) albumin normal at 3.9 (normal range is 3.5-5.0).

Many possibilities..: First, you should know that it's only mildly elevated, and a true diagnosis requires further testing and a more complete history and physical. But the differential diagnosis for "high serum globulin" is: leukemia, lupus, collagen diseases, syphilis, waldenstrom's macroglobulinemia, liver disease, Rheumatoid arthritis, ulcerative colitis, carcinoid syndrome, kidney disease, or chronic infection.

Probably nothing: This is such a minor elevation, it probably just means you were fighting off a cold or minor infection and the antibodies in your immune system (which are made of globulins) were slightly elevated when you took this test. I would repeat it when you are feeling completely well, and if it is still elevated, discuss further testing with your doctor.