Salivary secretory Ig A is characterized as a considerable indicator for assessment of the risk of pathological processes affecting periodontal tissues and structures. The initiation and progression of the excretory system disorders of pyelonephritis and nephrotic syndrome correlate to the necessity of frequent hospitalizations of patients in child's age. The aim of the study is to be evaluated the gingival health status in children suffering from pyelonephritis and nephrotic syndrome. In the study are applied clinical, laboratory and statistical methods. Among the children with diagnosed nephrotic syndrome is registered moderate negative correlation between salivary sIg A and PLI, as well as moderate negative correlation between salivary sIg A and GI. The healthy representatives of the study are characterized with significant negative correlation between the indicators of salivary sIg A and PLI, as well as significant negative correlation between salivary sIg A and GI. The participants with nephrotic syndrome are characterized with moderate negative correlation between the clinical indicator of PLI and salivary pH level. In the group of children with pyelonephritis is recorded significant negative correlation between PLI and salivary pH. Among the healthy representatives is registered extremely great negative correlation between both of the indicators of PLI and salivary pH. Great negative correlation between the clinical indicator of GI and salivary pH value is ascertained among the representatives of the three groups included in the study. The lowest level of secretory sIg A is registered among the participants suffering from nephrotic syndrome. The increased concentration of salivary secretory Ig A correlates to the lower levels of the PLI and GI. The reduced level of sIg A in saliva predisposes to initiation and progression of inflammatory reactions of the gingival tissue.