2 research outputs found
Trivalent influenza vaccine in patients on haemodialysis: impaired seroresponse with differences for A-H3N2 and A-H1N1 vaccine components
One hundred and one patients on haemodialysis, 21 patients on peritoneal dialysis and 30 healthy controls received a trivalent split vaccine containing 15 micrograms haemagglutinin of a recent influenza A-H3N2, influenza A-H1N1 and influenza B strain, respectively. Antibody production after four weeks was determined by the haemagglutination-inhibition test and expressed as response rate, protection rate and overall mean fold increase. The patients on haemodialysis revealed a diminished seroresponse, as compared to patients on peritoneal dialysis and controls. For influenza A-H3N2, this was less distinct than for the other two antigens. In patients on haemodialysis the protection rate was 66% against the A-H3N2 vaccine component (versus 85% in controls, not significant), but only 25% against A-H1N1 and 27% against B (versus 84 and 77% in controls, p less than 0.001). Duration of haemodialysis up to eight years did not affect seroresponse. Patients on haemodialysis who were primed for influenza A-H1N1 in the period 1947-1957, reacted markedly better to the A-H1N1 vaccine component than subjects of other priming periods. A booster injection of the same vaccine dosage four weeks after the first immunization, performed in 98 patients on haemodialysis, was of little value: it had virtually no effect with regard to influenza A-H1N1 and influenza B, and showed, though significantly better, still poor results for A-H3N2. The differences in seroresponse between the A-H3N2 and A-H1N1 vaccine component suggest a major defect of primary, and a minor defect of secondary humoral response in patients on haemodialysis. The consequences for vaccine policy in these patients are discussed
Flow measurements in dialysis shunts: lack of agreement between conventional Doppler, CVI-Q, and ultrasound dilution
BACKGROUND: Measuring flow in dialysis shunts is recommended to predict
imminent thrombosis. Multiple methods for measuring blood flow are in use.
Numerous ultrasound protocols exist which determine volume flow using a
conventional Doppler (CD) frequency shift analysis technique. All of these
are subject to potentially large errors. Quantitative colour velocity
index (CVI-Q) does not make use of the Doppler equation and is more
precise in vitro. Ultrasound dilution (UD) measures access flow during
dialysis in a non-operator-dependent way. The aim of the present study was
to compare these three methods of measuring access flow in vivo for
agreement with each other. METHODS: In 38 accesses flow was measured by
CD, CVI-Q, and UD. All measurements were done during dialysis. Agreement
was determined by intraclass correlation coefficient (ICC=R(i)) and
Bland-Altman analysis. RESULTS: ICC between UD and CVI-Q was R(i)=0.56.
ICC between UD and CD was R(i)=0.10, and ICC between CD and CVI-Q was
R(i)=0.16. Bland-Altman analysis revealed a bias (mean difference) of -38
ml/min between UD and CVI-Q, a bias of 1129 ml/min between UD and CD, and
a bias of 1167 ml/min between CVI-Q and CD. CONCLUSIONS: CD measurements
did not agree with UD or CVI-Q much higher values were recorded with the
former than with the latter two techniques. The agreement between UD and
CVI-Q measurements is low but reasonable. Caution must be applied in
comparing and interpreting values of access flow measured by different
techniques