Preemptive reduction of immunosuppression upon high urinary polyomavirus loads improves patient survival without affecting kidney graft function.
BACKGROUND
Polyomavirus (PV) is a major cause of kidney graft disease. Monitoring by polymerase chain reaction (PCR) on blood is currently recommended. In order to avoid irreversible lesions, we investigated the clinical impact of preemptive reduction of immunosuppression (IS) in kidney transplant recipients (KTR) upon detection of high urinary PV (Upv) load, including BK virus and JC virus.


METHODS
From 2000 to 2011, in our single center, 789 consecutive KTR were distributed into 4 groups, according to the maximal Upv levels (by PCR) during the first year and the therapeutic option: (A) Upv <104copies (cp)/mL (n=573), (B) ≥104Upv <107cp/mL (n=100), and (C) Upv ≥107cp/mL (n=116); in group C, the IS drug doses were reduced in subgroup Ca (n=102) only, as 14 patients (subgroup Cb) were at risk for graft rejection.


RESULTS
The preemptive reduction of IS (group Ca) increased patient survival as compared with all other groups (P<.05), did not modify graft function, and increased graft survival vs group A (risk ratio: 5.7, confidence interval: 1.8-18.1, P=.003). Differences for risk factors are as follows (groups Ca vs A): incidence of human leukocyte antigen (HLA) immunization (>5% panel reactive antibodies): 3% vs 8% (P=.05), number of HLA mismatches: 2.7 vs 2.5 (P=.049), and incidence of acute rejection: 9.8% vs 24.2% (P=.005). PV-associated nephropathy occurred only in group Ca (2% of total grafts) without effect on patient or graft outcome.


CONCLUSIONS
The reduction of IS in patients with high Upv loads is beneficial for patient survival and does not affect graft survival or graft function.
Department of Nephrology, Dialysis and Transplantation, Cliniques Universitaires de Bruxelles, Hôpital Erasme, Brussels, Belgium.
Emine Nilufer
http://orcid.org/0000-0001-5377-9335
EN
Broeders
Department of Nephrology, Dialysis and Transplantation, Cliniques Universitaires de Bruxelles, Hôpital Erasme, Brussels, Belgium.
Anwar
A
Hamade
Department of Nephrology, Dialysis and Transplantation, Cliniques Universitaires de Bruxelles, Hôpital Erasme, Brussels, Belgium.
Fadoua
F
El Mountahi
Research Center of Biostatistics, Epidemiology and Clinical Research, School of Public Health, Université Libre de Bruxelles, Brussels, Belgium.
Judith
J
Racapé
Department of Nephrology, Dialysis and Transplantation, Cliniques Universitaires de Bruxelles, Hôpital Erasme, Brussels, Belgium.
Jean-Michel
JM
Hougardy
Department of Nephrology, Dialysis and Transplantation, Cliniques Universitaires de Bruxelles, Hôpital Erasme, Brussels, Belgium.
Alain
A
Le Moine
Department of Nephrology, Dialysis and Transplantation, Cliniques Universitaires de Bruxelles, Hôpital Erasme, Brussels, Belgium.
Pierre
P
Vereerstraeten
D001739:BK Virus / Q000187:drug effects* / Q000302:isolation & purification; D005260:Female; D006084:Graft Rejection / Q000453:epidemiology* / Q000276:immunology / Q000821:virology; D006085:Graft Survival / Q000187:drug effects*; D006680:HLA Antigens / Q000276:immunology; D006801:Humans; D007165:Immunosuppression Therapy / Q000009:adverse effects* / Q000379:methods; D007166:Immunosuppressive Agents / Q000008:administration & dosage* / Q000627:therapeutic use; D007577:JC Virus / Q000187:drug effects* / Q000302:isolation & purification; D007674:Kidney Diseases / Q000453:epidemiology / Q000652:urine / Q000821:virology; D016030:Kidney Transplantation / Q000009:adverse effects*; D008297:Male; D008875:Middle Aged; D027601:Polyomavirus Infections / Q000453:epidemiology / Q000652:urine / Q000821:virology; D012189:Retrospective Studies; D012307:Risk Factors; D066027:Transplant Recipients / Q000706:statistics & numerical data; D016896:Treatment Outcome; D014412:Tumor Virus Infections / Q000453:epidemiology / Q000652:urine / Q000821:virology; D019562:Viral Load / Q000187:drug effects*; D014766:Viremia / Q000652:urine* / Q000821:virology
D006680:HLA Antigens; D007166:Immunosuppressive Agents
graft function; immunosuppression; kidney transplantation; polyomavirus; survival