Serum IgG and IgD and levels in some infectious and noninfectious diseases.

Serum IgG and IgD levels were determined in the following groups: professional blood donors, healthy smokers and patients with acute hepatitis, with acute salmonellosis, with hepatic cirrhosis, with cancer (prostate, lung and gastrointestinal tract) and with benign diseases of the same organs as the cancer patients. IgG was significantly increased in the groups of patients with hepatitis, hepatic cirrhosis and cancer. IgD values showed a wide dispersion in all the groups, which do not allow for comparisons among means. For that reason, linear regression analysis between IgG and IgD was done, the results being significant only in the two groups with infectious diseases (acute hepatitis and acute salmonellosis), which suggest that IgD could be involved in the immune response against their respective pathogenic agents.