Protective effect of nonspecific immunostimulation in postsplenectomy sepsis.

The enhanced risk of severe sepsis following splenectomy is now well recognized in both adult and pediatric patients. Prophylactic antibiotics and bacterial vaccines have been utilized with limited success to inhibit the high morbidity and mortality. This study reports the use of glucan, a beta-1,3-polyglucose, as a nonspecific immunostimulant for postsplenectomy pneumococcal sepsis. ICR mice were treated with glucan or glucose (5% w/v) following splenectomy or sham operation. Mice were then challenged with 1 X 10(9) Streptococcus pneumoniae intranasally. Glucan significantly increased survival in the splenectomy group (75%) compared to controls (27%). Phagocytic function, as measured by the clearance of 131I-triolein-labeled reticuloendothelial test lipid emulsion, was increased in the glucan group when compared to control glucose animals, both in the presence and absence of pneumococcal infection. Splenectomy alone did not significantly decrease phagocytic function. An increased leukocytosis in response to pneumococcal infection was observed in splenectomized glucan-treated animals. Nonspecific immunostimulation appears to have significant potential as a treatment strategy against postsplenectomy infection.