Graft versus host disease-related secretory immunoglobulin A deficiency in bone marrow transplant recipients. Findings in labial saliva.

Graft versus host disease-dependent decreases in salivary IgA levels were sought in labial gland saliva samples from bone marrow transplant recipients. Transplantation-associated, irradiation-related effects were also present, but these could be avoided if analyses were performed at 1 year or later after transplantation. Sampling of minor gland saliva eliminated the possibility of contamination with IgA-rich serum transudates arising from gingival or mucosal pathways which obscured results from previous studies using whole saliva samples. Patients with active extensive clinical disease had significantly depressed levels of salivary IgA. Since labial saliva is a principal source of total salivary IgA, the present findings may explain why patients with graft versus host disease are susceptible to infection via the sinobronchial portal.