Erythrocytosis after renal transplantation: risk factors and relationship with GFR.
Post-transplant erythrocytosis (PTE) has been increasingly recognized as a complication of kidney transplantation, and several risk factors have been defined. Recent evidence suggests renal function may also play a role in hematological recovery after transplantation and risk of PTE. In this study of kidney transplant recipients (n = 123), simultaneous Tc99m DTPA GFR (n = 710) and hemoglobin levels were compared with possible clinical determinants. The frequency histogram of post-transplant hemoglobin was bell-shaped and continuously distributed above and below the arbitrary definition of PTE, suggesting that PTE is not a separate disease entity. Hemoglobin reached a plateau at 12 months after transplantation and was correlated with isotopic GFR (r = 0.46, p < 0.001). This consistent and statistically independent relationship became prominent 3 months after transplantation. Hemoglobin was independently predicted by multivariate analysis by time after transplantation, presence of polycystic renal disease, greater serum albumin and reduced serum urea (which in turn were reflected by number of infective and rejection episodes), shorter kidney anastomosis time and a higher GFR, but not by immunosuppressive therapy. Rejection or infection episodes impaired hematological recovery. The independent determinants of GFR included hematological recovery. The independent determinants of GFR included hemoglobin level, kidneys from young, male donors, fewer HLA-DR mismatches and rejection episodes, shorter time on dialysis and greater azathioprine dose. Renal function was not altered by therapeutic phlebotomy. Determination of hemoglobin level by both donor and recipient variables supports the relevance of tubular and glomerular function in control of erythrocystosis after renal transplantation. A role for renin-angiotensin mediation in the alteration of intraglomerular hemodynamics and erythropoietin secretion is postulated.
Department of Renal Medicine, Westmead Hospital, Sydney, New South Wales, Australia.
B J
BJ
Nankivell
R D
RD
Allen
P J
PJ
O'Connell
J R
JR
Chapman
D000328:Adult; D004921:Erythropoietin / Q000502:physiology; D005260:Female; D005919:Glomerular Filtration Rate / Q000502:physiology*; D006084:Graft Rejection / Q000175:diagnosis / Q000503:physiopathology; D006452:Hemoglobinometry; D006650:Histocompatibility Testing; D006801:Humans; D007676:Kidney Failure, Chronic / Q000503:physiopathology / Q000601:surgery; D007677:Kidney Function Tests; D016030:Kidney Transplantation / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D007690:Polycystic Kidney Diseases / Q000503:physiopathology / Q000601:surgery; D011086:Polycythemia / Q000175:diagnosis / Q000503:physiopathology*; D011183:Postoperative Complications / Q000503:physiopathology*; D012084:Renin-Angiotensin System / Q000502:physiology; D012307:Risk Factors; D016896:Treatment Outcome
D004921:Erythropoietin