Splenectomy for trauma or haematological diseases, affects the bacterial clearance as well as the immunological status 
of the patient. Over-whelming postsplenectomy sepsis syndrome carries 50-80% mortality. The ability of the spleen, liver and kidney to filter inoculated Staphylococcs aureus and the serum staphylococcal anti-DNase, was investigated in totally and partially splenectomized Schistosoma mansoni infected mices (n=120). Group Gl (n=60) was treated with the 
antischistosomal praziquantel six weeks post infection, while G2 (n=60) was left untreated control. Two weeks later, total 
(G1T and G2T), 75% partial (G1P and G2P) or sham splenectomy (G1C and G2C) were respectively performed. After four 
weeks, all animals were inoculated with ATCC 25923 Staphylococc aureus (3 x 107 C.F.U/ml saline/mouse). Twenty-four 
hours later, the liver, spleen, kidney, and serum were collected for bacterial counting and serum staphylococcal anti-Dnase testing. The Student's t, Wilcoxon two-sample and ANOVA tests were used for the statistical analysis. A significantly higher bacterial counts in the splenic remnant of G1P vs. G1C, and in the liver and kidney of G1T vs. G1C was found. Serum Staphylococcal anti-DNase level was more evident in G1 at almost the same mean log value of 0.6 and 0.5 but at different percentages of positivety (G1T=63 .6%, GlP=42.8%, G1C=29.4%). In conclusion, in the treated Schistosoma infected mice, the spleen and even a part of it, is an efficient bacterial filter and partial splenectomy may be preferred than total splenectomy.
Praziquantel treatment favored the host's power to filter bacteria and to produce antibody.