there is salivary/secretory igA and serum igA. it's essentially inflammatory response right, so yes possibly infection. more info:
"Increased serum immunoglobulin concentrations occur due to polyclonal or oligoclonal immunoglobulin proliferation in hepatic disease (hepatitis, liver cirrhosis), connective tissue diseases, acute and chronic infections, as well as in the cord blood of neonates with intrauterine and perinatal infections.
Elevation of immunoglobulin A may occur in monoclonal gammopathies such as multiple myeloma, primary systemic amyloidosis, monoclonal gammopathy of undetermined significance, and related disorders.
Decreased levels are found in patients with primary or secondary immune deficiencies."
we already discussed a future zinc test for you elsewhere but this IgA issue ties it back in. a little science...
IgA and inflammation:
Association of inflammation with raised serum IgA in ankylosing spondylitishttp://www.ncbi.nlm.nih.gov/pmc/article ... 1-0019.pdf
"The mean serum IgA was 38% higher in patients (306.9 mg/dl) than in controls (222 7 mg/dl) (P<0 .005), but there was no significant difference in IgG and IgM levels. Increased IgA was associated with laboratory parameters of active inflammatory disease. The mean IgA in patients having an erythrocyte sedimentation rate (ESR) equal to or greater than 15 mm/h was 369 mg/dl, 65% higher than in controls (P<0 .001), whereas there was no significant difference between controls and patients with an ESR of less than 15 mm/h. The mean IgA in patients having a C-reactive protein (CRP) level equal to or greater than 15 ,ug/ml (15 mg/1) was 387*8 mg/dl, 74% higher than in controls (P<0 .001), and again there was no significant difference between controls and patients with CRP levels less than 15 pg/ml. (SI conversion: g/l=mg/dl x 0.01)."
and another interesting tidbit... zinc and IgA
[Plasma zinc levels in elderly hospitalized subjects. Correlation with other nutritional and immunological markers and survival].http://www.ncbi.nlm.nih.gov/pubmed/6320399
"Plasma zinc concentrations were significantly lower in the elderly patients, as compared to the younger subjects (p 0.001) ... Immunological tests in the elderly show moderate lymphopenia, high serum IgA and frequent depression of delayed cutaneous hypersensitivity to DNCB and PHA."
the correlation btw low zinc and high IgA did not apparently attain the significance grail, at least not using their study design, which i can't evaluate not having access to full text/raw data.
aside: not to mention zinc and ESR, interesting...:
Plasma zinc and its relationship to clinical symptoms and drug treatment in rheumatoid arthritishttp://www.ncbi.nlm.nih.gov/pmc/articles/PMC1000551/
"Zinc levels correlated positively with serum albumin, and there was an inverse correlation between zinc levels and both ESR and globulin concentration
in all rheumatoid patients. However, the correlation coefficient varied in the different treatment groups. The results of this study support the hypothesis that low plasma zinc level in rheumatoid arthritis is one of the nonspecific features of inflammation