Sex and the pregnant kidney: does renal allograft gender influence gestational renal adaptation in renal transplant recipients?

BACKGROUND: Animal work indicates that ovarian hormones are important in initiating and maintaining enhanced renal function in pregnant rats and that a renal response resembling pregnancy can be provoked in male rats exposed to pregnancy hormones. Women becoming pregnant following renal transplantation provide an opportunity to compare the functional response of male and female allografts to the gestational endocrine environment. METHODS: This retrospective observational study included 20 renal allograft recipients (age 29.7 +/- 2.4 yrs) (mean +/- SE) who had 22 pregnancies beyond 24 weeks (gestation at delivery 35.5 +/- 0.6 weeks). Donor characteristics, transplant details, renal follow-up data, and information about pregnancy and allograft function were obtained from hospital notes. RESULTS: Thirteen women received male allografts (donor age 30.0 +/- 3.9 years) (mean +/- SEM) and 7 women, female allografts (donor age 45.1 +/- 6.0 years) (P = .04). There were no significant differences between the two groups in maternal recipient age, transplant to pregnancy interval, antenatal complications, pregnancy outcome, or postnatal graft function. Compared to prepregnancy values serum creatinine (SCr) decrements and augmented 24-hour creatinine clearance (CrCl) were observed over the first trimester in both male and female allografts: Delta CrCl from 106.8 +/- 13.2 mL/min to 114.4 +/- 11.4 mL/min (35.6% increase) and 71.8 +/- 7.4 to 89.5 +/- 11.3 mL/min (24.7% increase), respectively, and Delta SCr from 90.1 +/- 5.4 micromol/L to 73.6 +/- 6.6 micromol/L (17.8% decrease) and 99.8 +/- 9.7 micromol/L to 78.0 +/- 5.7 micromol/L (13.5% decrease), respectively. Differences between the two groups did not reach statistical significance. CONCLUSIONS: Donor gender and/or age do not appear to influence the gestational renal response in kidney transplant recipients.

Glomerular heteroporous membrane modeling in third trimester and postpartum before and during amino acid infusion.

Human pregnancy is associated with substantial increments in glomerular filtration rate (GFR) and renal plasma flow (RPF). We have previously demonstrated that permselectivity to neutral dextrans is altered in pregnancy, theoretical analysis of the dextran sieving curves suggesting that elevated GFR is due to increased RPF and decreased glomerular oncotic pressure (pi(GC)) with no evidence of increased transglomerular hydrostatic pressure difference (DeltaP). These conclusions have been challenged, with claims that the rise in GFR is primarily a result of a decrement in pi(GC). With refined laboratory and infusion protocols, we have reexplored the determinants of ultrafiltration in a serial study of 11 healthy women in late pregnancy (LP) and 4 mo postpartum (PP), both in the baseline state and after increasing GFR and RPF by infusion of amino acids. Results were analyzed using two computer modeling programs. Increased GFR in LP (38%, P < 0.05) was due to a combination of elevated RPF (22%) and a decrement in pi(GC) and associated with an increased ultrafiltration coefficient, without evidence of increased DeltaP, and additional amino acid-provoked GFR increments (P < 0.05) produced similar findings. In addition, refined methodology permitted collection of sufficient data on excreted large-radii dextrans (>60 A) to better define the nondiscriminatory "shunt" pathway (omega(0)) and the standard deviation of pore size (S) about the mean radius of the distribution. Thus it was possible to demonstrate that the physiological increase in total protein excretion in LP is associated with a prominent shunt and an upward shift in breadth of distribution of pore sizes. This ability to quantify omega(0) and S will now permit better evaluation of the pathophysiological changes in the glomerulus associated with pregnancy in women with renal disease and in gravidas developing preeclampsia.

Thirty-two cases of mesothelioma in Victoria, Australia: a retrospective survey related to occupational asbestos exposure.

Mesotheliomas have been reported in four states in Australia. Crocidolite has been mined and milled at Wittenoom in West Australia where five cases of mesothelioma were reported after exposure of high intensity. The 32 cases of mesothelioma reported in this paper occurred during a period of 11 years in Victoria; 29 were pleural and three peritoneal. There were 22 autopsies. End occupations were misleading in 66% of cases. Two of the three subjects with peritoneal mesothelioma were siblings, and there was no evidence of occupational or other exposure to asbestos in either. There was a significant prevalence of pulmonary asbestos bodies in the tumour series as compared with an unselected consecutive series of 200 routine autopsies (0.01 greater than P greater than 0.001). The occupational history was as effective a method of assessing 'true' asbestos exposure as the pulmonary asbestos body count. Five cases had had a duration of exposure of one year or less, but they had had heavy exposure. The latent interval before tumour development was 25 years or longer in each case. There was no known exposure to asbestos in five cases (16%). The rare association of mesothelioma with types of asbestos other than crocikolite may not exist and could be explicable on the basis of the proportion (16%) of these tumours arising randomly in the population.