Saliva composition in Indian children with chronic protein-energy malnutrition.

The composition of paraffin-stimulated and unstimulated whole saliva was compared between two groups of 8-12-year-old Indian children-one group with severe to moderate chronic protein-energy malnutrition (PEM group) and an age- and sex-matched control group with normal protein status or mild PEM. The classification of PEM was based on anthropometric measurements compared with Indian standards. Stimulated saliva was analyzed for the following variables: electrolytes (Na+, K+, Ca2+, Cl-, and PO4(3-)), total protein, hexosamines, fucose, sialic acid, and amylase. Unstimulated saliva samples were analyzed for total protein, salivary and myeloperoxidase, thiocyanate, lactoferrin, lysozyme, a bacteria-agglutinating protein (BAGP), total IgG, total IgA, and specific anti-S. mutans IgA. The results show that the PEM group had a reduced secretion rate of stimulated but not unstimulated saliva. Further, the Ca2+ and Cl- concentrations in stimulated saliva were significantly lower in the PEM group compared with the control group, but the other electrolyte levels were similar. No differences were found in total protein concentration or glycoprotein bound carbohydrates in stimulated saliva between the two groups, but the quantity of total protein secreted per min was reduced by 20% in the PEM group. Significantly lower levels of lactoferrin, BAGP, and anti-S mutans IgA were found in unstimulated saliva from children in the PEM group, but significantly higher levels of total IgG. We conclude that children with severe or moderate PEM, who have reduced secretion rate, buffer capacity, lower Ca2+, and protein secretion in stimulated saliva, also have impaired immunological and agglutinating defense factors in unstimulated saliva.