Table 4.

Torque Teno Virus (TTV) Levels Stratified According to Clinical Characteristics of the Study Cohort at the Time of TTV Assessment

	TTV, Copies/mL, Median (IQR)
Characteristic	Variable Positive	Variable Negative	P Value
Laboratory parameter
eGFRa,b >37 mL/min/1.73 m2	3.3 × 108 (1.0 × 107–2.2 × 109)	2.5 × 108 (3.2 × 107–3.9 × 109)	.124
Urinary protein:creatinine ratiob >198	9.8 × 107 (3.1 × 107–5.1 × 109)	4.5 × 108 (2.2 × 107–5.1 × 109)	.484
Microhematuriac	8.5 × 107 (4.0 × 107–3.8 × 109)	3.5 × 108 (3.1 × 107–3.4 × 109)	.595
Immunosuppression
Triple immunosuppression	6.1 × 107 (3.2 × 107–3.7 × 109)	4.1 × 108, d	.945
Prednisolone >5 mgb	6.1 × 107 (3.1 × 107–1.7 × 109)	2.7 × 109 (1.2 × 108–7.1 × 109)	.758
Mycophenolic acid	1.2 × 108 (3.2 × 107–3.7 × 109)	1.3 × 107, d	.046
Mycophenolic acid above medianb,e	1.3 × 108 (3.2 × 107–3.0 × 109)	4.5 × 108 (2.0 × 107–3.9 × 109)	.969
Tacrolimus	1.5 × 108 (3.2 × 107–3.7 × 109)	1.6 × 107, d	.022
Tacrolimus trough level >7 ng/mLb	1.1 × 109 (4.8 × 107–3.9 × 109)	1.3 × 108 (6.4 × 106–2.5 × 109)	.712
Belatacept	1.9 × 106, d	9.9 × 107 (3.2 × 107–3.7 × 109)	.030
Virology
BKV PCR positive	3.1 × 109 (5.1 × 107–1.5 × 1010)	8.5 × 107 (3.1 × 107–1.7 × 109)	.029
CMV PCR positive	1.3 × 108 (1.7 × 107–2.7 × 109)	8.6 × 108 (3.2 × 107–3.9 × 109)	.677
TTV detection time >127 d after transplantationb	2.5 × 108 (3.2 × 107–4.9 × 109)	5.3 × 108 (3.1 × 107–3.7 × 109)	.770

The Mann–Whitney U test was used for comparing continuous data. Exact tests were used where applicable.

Abbreviations: BKV, BK polyomavirus; CMV, cytomegalovirus; eGFR, estimated glomerular filtration rate; IQR, interquartile range; PCR, polymerase chain reaction; TTV, torque teno virus.

^aeGFR was calculated using the Modification of Diet in Renal Disease equation [7].

^bCutoff defined by median.

^cMicrohematuria was assessed by dipstick analysis or light microscopy.

^dInterquartile range not applicable due to low number of events per group.

^eFive hundred forty milligrams for enteric-coated mycophenolic acid and 1500 mg for non-enteric-coated mycophenolic acid.