Full-term delivery following nephrectomy

Pregnancy and birth after kidney donation: the Norwegian experience

Reports on pregnancies in kidney donors are scarce. The aim was to assess pregnancy outcomes for previous donors nationwide. The Medical Birth Registry of Norway holds records of births since 1967. Linkage with the Norwegian Renal Registry provided data on pregnancies of kidney donors 1967-2002. A random sample from the Medical Birth Registry was control group, as was pregnancies in kidney donors prior to donation. Differences between groups were assessed by two-sided Fisher's exact tests and with generalized linear mixed models (GLMM). We identified 326 donors with 726 pregnancies, 106 after donation. In unadjusted analysis (Fisher) no differences were observed in the occurrence of preeclampsia (p = 0.22). In the adjusted analysis (GLMM) it was more common in pregnancies after donation, 6/106 (5.7%), than in pregnancies before donation 16/620 (2.6%) (p = 0.026). The occurrence of stillbirths after donation was 3/106 (2.8%), before donation 7/620 (1.1%), in controls (1.1%) (p = 0.17). No differences were observed in the occurrence of adverse pregnancy outcome in kidney donors and in the general population in unadjusted analysis. Our finding of more frequent preeclampsia in pregnancies after kidney donation in the secondary analysis must be interpreted with caution, as the number of events was low.

The solitary kidney: a model of chronic hyperfiltration in humans

Reduction of renal mass (11/12) in rats leads to progressive azotemia, proteinuria, and hypertension. Less extensive renal ablation resulting from uninephrectomy also accelerates the progression of focal glomerulosclerosis (FGS) induced by experimental diabetes, renal irradiation, aminonucleoside nephrosis, or aging. The consequence of the absence of one kidney in man are examined in three different clinical situations. Unilateral renal agenesis seems to predispose to the development of FGS, but most reports include isolated cases and the true incidence of FGS is not known. The solitary kidney following uninephrectomy for acquired unilateral disease undergoes a compensatory rise in glomerular filtration rate (GFR) that remains stable for several decades. Finally, kidney donors followed for over 2 decades show unimpaired GFR, elevated at 70% to 80% of the normal (two-kidney) GFR. Some donors develop mild, nonprogressive proteinuria. Their incidence of hypertension matches that in the control population. Thus, hyperfiltration secondary to 50% reduction of renal mass in humans does not lead to loss of function of the remaining parenchyma.

Effects of unilateral nephrectomy during early pregnancy

Litter data and kidney growth parameters in Wistar rats uninephrectomized (UNX) or sham-operated (SO) on the 5th-7th day of gestation, and in unoperated controls (C) were investigated at 1 day and at 6 wk postpartum. Gestation period, litter size, sex ratio of pups, and pup weight at birth did not differ among the groups. At 6 wk, pups from UNX mothers displayed retarded growth. Compensatory kidney growth following UNX in pregnant rats was predictable for wet weight, but dry weight compensation was transient and limited.

Hypertension and proteinuria: long-term sequelae of uninephrectomy in humans

Renal function and blood pressure were assessed in 52 renal allograft donors 10 years or more following uninephrectomy, and their current function compared to their pre-uninephrectomy function as well as to age- and sex-matched control subjects consisting of inpatient potential renal donors and a normal "outpatient" population. The results show no significant deterioration in renal function as determined by serum creatinine or creatinine clearance, as a function of years post-uninephrectomy or age at the time of donation. A higher incidence of proteinuria and hypertension was found in male donors as compared to their pre-uninephrectomy values and to age- and sex-matched, inpatient and outpatient control subjects. Female donors had increased proteinuria when compared to pre-uninephrectomy and to age-matched, inpatient potential donors. However, the extent of proteinuria and hypertension was not significantly different from outpatient age-matched females with two kidneys. In our population, uninephrectomy is associated with mild proteinuria and hypertension.