Value of booster immunisation with influenza vaccine in patients undergoing haemodialysis.

Value of booster immunisation with influenza vaccine in patients undergoing haemodialysis The public health authorities ofmost Western countries recommend annual influenza vaccination for some patients, including those with end stage renal disease.' Patients on haemodialysis, however, show impaired antibody responses after a single influenza vaccination, which may result in insufficient protection.2 These patients also respond poorly to hepatitis B vaccine, but a booster immunisation will produce protective antibody titres.3 In a large group of patients on haemodialysis we therefore attempted to induce adequate protection against influenza by performing a booster vaccination. Ninety eight patients in a stable condition who were undergoing long term intermittent haemodialysis took-part. They were aged 17 to 76 (median 57) years and had been undergoing haemodialysis for one month to 13 years (median two years). None had received steroids or immunosuppressive drugs for at least six months. Twenty nine healthy volunteers aged 19 to 69 (median 27) years served as controls. A commercially available trivalent split virus vaccine (Alorbat, Asta Werken, Bielefeld, Federal Republic of Germany) containing 15 Isg haemagglutinin of A/Philippines/2/82 (H3N2), A/Chile/l/83 (HIN,), and B/USSR/100/83 was administered by intramuscular injection in the upper arm on day 0 and day 30 (booster immunisation). Serum was obtained on days 0, 30, and 60. The study took place in the autumn of 1985. Antibody titres were determined twice in paired sera by the haemagglutination inhibition technique, and geometric mean titres were calculated. A fourfold or more rise in titre was considered to be a satisfactory response, and protection was defined by titres of >-100 against influenza A and ¢200 against ether treated influenza B.4 Before vaccination geometric mean titres against the three virus strains did not differ between the groups (table). After the first injection the patients undergoing dialysis had significantly lower geometric mean titres than the controls for all viruses tested (p<0-001, Wilcoxon rank test). Booster vaccination did not influence the final titres reached. Among the initially unprotected patients and controls significantly fewer of the patients showed a more than fourfold rise in titre against the three viruses (H3N2 and B p<0*05, HIN1 p<0001; x2 test) after the first injection (table). Booster immunisation produced greater than fourfold rises in titres against H3N2, HIN, and B in, respectively, a further 14%, 8%, and 0% ofthe patients and 5%, 8%, and 4% of the controls. The seroconversion rate to protective titres against H3N2 and B was also significantly …