Assessing relative risks of infection and rejection: a meta-analysis using an immune function assay.
BACKGROUND
Long-term use of immunosuppressants is associated with significant morbidity and mortality in transplant recipients. A simple whole blood assay that has U.S. Food and Drug Administration clearance directly assesses the net state of immune function of allograft recipients for better individualization of therapy. A meta-analysis of 504 solid organ transplant recipients (heart, kidney, kidney-pancreas, liver and small bowel) from 10 U.S. centers was performed using the Cylex ImmuKnow assay.


METHODS
Blood samples were taken from recipients at various times posttransplant and compared with clinical course (stable, rejection, infection). In this analysis, 39 biopsy-proven cellular rejections and 66 diagnosed infections occurred. Odds ratios of infection or rejection were calculated based on measured immune response values.


RESULTS
A recipient with an immune response value of 25 ng/ml adenosine triphosphate (ATP) was 12 times (95% confidence of 4 to 36) more likely to develop an infection than a recipient with a stronger immune response. Similarly, a recipient with an immune response of 700 ng/ml ATP was 30 times (95% confidence of 8 to 112) more likely to develop a cellular rejection than a recipient with a lower immune response value. Of note is the intersection of odds ratio curves for infection and rejection in the moderate immune response zone (280 ng/ml ATP). This intersection of risk curves provides an immunological target of immune function for solid organ recipients.


CONCLUSIONS
These data show that the Cylex ImmuKnow assay has a high negative predictive value and provides a target immunological response zone for minimizing risk and managing patients to stability.
Kowalski
Richard J
RJ
Cylex Incorporated, Columbia, MD 21045, USA. rkowalski@cylex.net
Post
Diane R
DR
Mannon
Roslyn B
RB
Sebastian
Anthony
A
Wright
Harlan I
HI
Sigle
Gary
G
Burdick
James
J
Elmagd
Kareem Abu
KA
Zeevi
Adriana
A
Lopez-Cepero
Mayra
M
Daller
John A
JA
Gritsch
H Albin
HA
Reed
Elaine F
EF
Jonsson
Johann
J
Hawkins
Douglas
D
Britz
Judith A
JA
D006084:Graft Rejection / Q000453:epidemiology* / Q000276:immunology; D006801:Humans; D007239:Infections / Q000453:epidemiology* / Q000276:immunology; D016017:Odds Ratio; D016377:Organ Transplantation / Q000009:adverse effects*; D011183:Postoperative Complications / Q000453:epidemiology* / Q000276:immunology; D012189:Retrospective Studies; D012306:Risk