Surgical transplant physical examination: correlation of renal resistance index and biopsy-proven chronic allograft nephropathy.
BACKGROUND
Chronic allograft nephropathy (CAN) remains the leading cause of late renal allograft loss that is minimally responsive to therapy once graft dysfunction is clinically evident. A screening test capable of identifying individuals at high risk for CAN would be a valuable adjunct to patient care, but to be cost effective, should be administered during routine evaluations by transplantation clinicians.


METHODS
We have compared the resistive index (RI) as measured by Doppler ultrasonography with subsequent biopsy findings on 91 renal allograft recipients who had a subsequent protocol-directed biopsy at least 3 months after renal transplant. All ultrasonography was performed by the transplantation surgical staff without involving the radiology department or a separate appointment time.


RESULTS
Twenty-one patients had RI >/= 80 (average 621 days posttransplantation). Among these individuals, the subsequent incidence of CAN was 38%. Length of time between initial assessment of increased RI and biopsy-proved CAN averaged 233 days. The remaining 70 patients with RI < 80 had an incidence of CAN of 11.4% (p = 0.018). There were minimal complications from these biopsies. Sensitivity and specificity of an elevated RI in predicting CAN were 50% and 83%, respectively. The negative predicted value of an elevated RI in determination of CAN was 89%.


CONCLUSIONS
These results suggest that elevated RI is an early predictor of histologically relevant CAN, possibly a result of burgeoning vasculopathy. The technical expertise required to make this appraisal is well within the capabilities of transplantation surgeons and trainees. Early evidence of CAN may allow for a targeted change in therapy before clinically significant injury. Ultrasonography should become a routine part of a transplantation clinic evaluation.
Elster
Eric A
EA
Transplantation Branch, National Institute of Diabetes, Digestive and Kidney Diseases, National Institutes of Health, Department of Health and Human Services, Bethesda, MD 20892, USA.
Hale
Douglas A
DA
Mannon
Roslyn B
RB
Cendales
Linda C
LC
Kleiner
David
D
Swanson
S John
SJ
Kirk
Allan D
AD
D000293:Adolescent; D000328:Adult; D000368:Aged; D001706:Biopsy; D005260:Female; D006084:Graft Rejection / Q000000981:diagnostic imaging / Q000473:pathology; D006801:Humans; D015994:Incidence; D007668:Kidney / Q000000981:diagnostic imaging / Q000473:pathology; D007674:Kidney Diseases / Q000000981:diagnostic imaging* / Q000473:pathology; D007677:Kidney Function Tests; D016030:Kidney Transplantation; D008297:Male; D008875:Middle Aged; D010808:Physical Examination; D011183:Postoperative Complications / Q000000981:diagnostic imaging* / Q000473:pathology; D012680:Sensitivity and Specificity; D014184:Transplantation, Homologous; D018608:Ultrasonography, Doppler