Incidence, risk factors, and outcome of BK polyomavirus infection after kidney transplantation

Table 2 Characteristics of kidney recipients with or without BK-viremia

Variables	Median (IQR) or n (%)		P
	No BKV group	BKV group
Patients	569	60	-
Recipient Male : Female	333 : 236	39 : 21	0.4076
Caucasian ethnicity	255/569 (44.8)	24/60 (40)	0.4977
Afro-Caribbean ethnicity	94/569 (16.5)	20/60 (33.3)	0.0024
Recipient age (years)	47 (36-55)	48.5 (37-53.25)	0.7263
Recipient age ≥ 60 yr	74/569 (13)	10/60 (16.7)	0.4255
Recipient BMI ≥ 30 kg/m2	79/569 (13.9)	8/60 (13.3)	1.0000
Pre-transplant diabetes	77/569 (13.5)	6/60 (10)	0.5499
Pre-transplant cardiovascular disease	55/569 (9.7)	7/60 (11.7)	0.5473
Recipient CMV IgG positive	391/569 (68.7)	40/60 (66.7)	0.7707
Primary renal disease
Glomerular disease	167/569 (29.4)	18/60 (30)
Polycystic kidney disease	62/569 (10.9)	9/60 (15)
Tubular-interstitial nephropathy	77/569 (13.5)	4/60 (6.7)
Diabetic nephropathy	45/569 (7.9)	4/60 (6.7)
Hypertension	47/569 (8.3)	8/60 (13.3)
Unknown renal disease	130/569 (22.8)	11/60 (18.3)
Other renal disease	41/569 (7.2)	6/60 (10)
Haemodialysis	266/569 (46.7)	28/60 (46.7)	1.0000
Peritoneal dialysis	123/569 (21.6)	13/60 (21.7)	1.0000
Pre-emptive transplant	72/569 (12.7)	8/60 (13.3)	0.8395
Panel-reactive antibody test > 50%	83/569 (14.6)	18/60 (30)	0.0047
Primary transplant	497/569 (87.3)	53/60 (88.3)	1.0000
Deceased donor	357/569 (62.7)	38/60 (63.3)	1.0000
Donation after brain death donor	235/569 (41.3)	27/60 (45)	0.5848
ABO-incompatible transplant	21/569 (3.7)	4/60 (6.7)	0.2856
Donor age (yr)	47 (38-57)	51.5 (40.75-60.25)	0.0483
Donor age ≥ 60 yr	115/569 (20.2)	17/60 (28.3)	0.1808
Donor-recipient gender mismatch	308/569 (54.1)	32/60 (53.3)	1.0000
Donor CMV IgG positive	323/569 (56.8)	31/60 (51.7)	0.4947
Cytomegalovirus D+R- immunization	79/569 (13.9)	4/60 (6.7)	0.1582
Cold ischemia time (h)	12 (4-16)	12 (4-17.25)	0.9920
Cumulative HLA mismatch	3 (2-4)	3 (2-5)	0.0759
HLA mismatch > 4	76/569 (13.4)	16/60 (26.7)	0.0110
HLA-A mismatch	1 (1-2)	1 (1-2)	0.6079
HLA-B mismatch	1 (1-1)	1 (1-2)	0.1896
HLA-DR mismatch	1(0-1)	1 (0-1.25)	0.0482
Induction treatment
Anti-IL2-receptor antagonist	388/569 (68.2)	43/60 (71.7)
Rabbit anti-thymocyte globulin	156/569 (27.4)	13/60 (21.7)
Rituximab	21/569 (3.7)	4/60 (6.7)
Alemtuzumab	3/569 (0.5)	0/60 (0)
Muromonab-CD3	1/569 (0.2)	0/60 (0)
Maintenance immunosuppression
CyA-based scheme	385/569 (67.7)	40/60 (66.7)
Tacrolimus-based scheme	182/569 (32.0)	20/60 (33.3)
MMF-containing scheme	490/569 (86.1)	54/60 (90)
AZA-containing scheme	80/569 (14.1)	6/60 (10)
CNI-free scheme	2/569 (0.4)	0/60 (0)
Steroid-free scheme	13/569 (2.3)	1/60 (1.7)
Cytomegalovirus prophylaxis	224/569 (39.4)	17/60 (28.3)	0.1239
DGF	152/569 (26.7)	15/60 (25)	0.8783
BPR within 30 d of transplantation	54/569 (9.5)	13/60 (21.7)	0.0073

BKV: BK-virus; IQR: Interquartile range; BMI: Body mass index; CMV: Cytomegalovirus; IgG: Immunoglobulin class G; HLA: Human leukocyte antigen; CyA: Cyclosporine; MMF: Mycophenolate mofetil; AZA: Azathioprine; CNI: Calcineurin inhibitor; DGF: Delayed graft function; BPR: Biopsy-proven rejection.