5treptococcus pneumoniae is the most common cause of serious bacterial illnesses in post-splenectomy child patients. Because of the increased risk of Pneumococcal infection, vaccination with Polyvalent Pneumococcal vaccine is suitable. It is recommended 14 days before the splenectomy or at least 14 days after the operation. The effectiveness of the vaccination is about 70% in Post-splenectomy patients. For asPlenic patients, re-imunization is recommended after 3 - 5-year intervale. In 52 Post-splenectomy children (29 mates and 23 females, aged 5 - 18 years), the antibody response was investigated 4 weeks after vaccination with the 23-valem Polysaccharide Pneumococcal vaccine and in 22 children (10 mates and 12 females) is was followed uP after 3 years. Levels of specific IgGz antibodies against capsular Polysaccharide antigens of Pneumococci (PCP) esere measured before vaccination, 4 weeks and 3 years after vaccination by ELI5A. But there is no standardized method for the determination of antibodies against Pneumococci, nor for the evaluation of criteria of the immune response to this vaccine. Results do not show a decreased antibody response in Post-splenectomy patients after vaccination with 23-valem Pneumococcal vaccine. But no response to Pneumococcal vaccination was obtained in 9 sPlenectomized patients. The concentrations of specific IgGz antibodies in the third year following the vaccination compared with those before the vaccination, stimulated a discussion about the suitability of re-vaccination 3 - 5 years after the first vaccination in sPlenectomized child patients.

        Key words: splenectomy, 5treptococcus pneumoniae, Pneumococcal vaccine, IgGz antipolysaccharide antibodies, immune response