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To ascertain the frequency, epidemiology, and risk factors of posttransplant diabetes mellitus (PTDM), a retrospective analysis of all first renal transplantations, without personal history of diabetes (DM) and with a follow up >or=6 months, was performed. All patients received methylprednisolone (0.5-1 g IV) immediately prior to surgery, followed by immunosuppression including steroids, cyclosporine, and azathioprine most frequently. Early hyperglycemia was defined as values >126 mg/dL during the first week after transplantation and DM by 2 blood glucose levels of >126 mg/dL after the first month of follow-up. Included were 163 patients, namely, 57.6% males and 66% recipients of a deceased donor and 12% with a first-degree family history of DM. Mean age at transplantation was 39 years (range, 17-70 years) with a mean follow-up of 64 months. Among the 163 total subjects, some developed PTDM with frequencies of 7.5%, 13%, and 23% at 1, 5, and 10 years, respectively. Among patients with a first-degree family history of DM, 37% developed PTDM compared with 14% of those without it (odds ratio [OR] = 3.6; P < .05). Early hyperglycemia was observed in 55/92 patients, 15 of whom developed PTDM. Among patients with PTDM, the frequency of early hyperglycemia was 87% compared with 54% among those who did not develop this complication (OR = 5.4; P < .05). We confirmed a high frequency of PTDM, identifying risk factors such as a first-degree family history of DM and the development of early hyperglycemia, which should be taken into account to increase our diagnostic sensitivity and improve therapeutic individualization among renal transplant patients.

To describe HLA antigen distribution, looking for possible markers of renal disease in Mapuche and non-Mapuche people in the renal transplantation program, we reviewed data from 1297 histocompatibility studies of the Chilean national renal transplantation program (421 donors and 876 recipients), performed between 2000 and 2005. Mapuche people were classified according to their family surnames. The most frequent antigens found among the total Chilean population were A2 (48%), A19 (33%), B16 (33%), B35 (26%), DR4 (38%), and DR6 (28%), without significant differences between donors and recipients. Among the 114 individuals (9%) classified as Mapuche, the most frequent antigens were A28 (49%), A2 (44%), B16 (63%), B35 (24%), DR4 (48%), and DR8 (30%), with A28/B16/DR4 as the most common haplotype. In contrast, A28, B16, DR4, and DR8 were significantly more frequent in Mapuche compared with non-Mapuche people. B8 was significantly more frequent in Mapuche recipients than in non-Mapuche recipients and Mapuche donors. The higher frequency of some HLA antigens in Mapuche people was confirmed, possibly corresponding to ethnic markers. The special concentration of B8 among Mapuche recipients might represent a genetic factor predisposing to chronic renal disease in this human group.

Previous studies have demonstrated higher concentrations of some histocompatibility antigens in Mapuche people compared with non-Mapuche Chileans in the renal transplantation program. With the aim of evaluating whether those antigenic differences might induce differences in the outcomes of renal transplantation among patients belonging to that ethnic group, we reviewed HLA studies and at least 6 months follow-up of all patients with a first kidney transplant between 1980 and 2006. The 248 patients had a mean age of 37.6 years, 40% were females, and 48% had living related donors. The mean kidney follow-up was 90 months and patient follow-up was 106 months. Thirty-nine patients (16%) were classified as Mapuche, according to their surnames, including 16 women with overall mean age of 34.5 years, and 14 had been transplanted from a living related donor. Mapuche patients received organs with better HLA matching expressed as number of identities (3.4 +/- 0.1 versus 2.8 +/- 0.1 among non-Mapuche; P < .05), and the proportion receiving organs with > or = 3 compatibilities was significantly higher (Mapuche 38% versus non-Mapuche 22%; P < .05). Kaplan-Meier survival curves showed nonsignificant differences in kidney survival: 86% at 5 years and 68% at 10 years in Mapuche; and 83% and 65%, respectively, for non-Mapuche. Patient survival rates were 97% at 5 years and 86% at 10 years in the Mapuche group versus 91% and 79%, respectively, in the non-Mapuche group; both results were not significantly different. Our results showed similar outcomes of kidney and patient survivals among Mapuche people even when they received organs with better HLA matches.

Background: Chronic allograft nephropathy (CAN) is the most frequent cause of chronic dysfunction and late loss of renal allografts. Epithelial mesenchymal transition (EMT) has been identified as responsible for the presence of activated interstitial fibroblasts (myofibroblasts) and transforming growth factor beta (TGF-beta)/Smad is the key signaling mediator. It has been proposed that the bone morphogenetic protein 7 (BMP-7) antagonist, Gremlin, could participate in EMT, as a downstream mediator of TGF-beta., Methods: We evaluated 33 renal allograft biopsies, 16 of which showed CAN, versus 17 controls. By in situ hybridization we studied the expression of TGF-beta and Gremlin mRNA. Gremlin, BMP-7, E-cadherin, and alpha-smooth muscle actin (alpha-SMA) proteins were evaluated by immunohistochemistry and Smad3 activation by Southwestern. In cultured human tubuloepithelial cells (HK2 cell line), Gremlin induction by TGF-beta was studied by confocal microscopy., Results: Among renal biopsies of transplanted patients with CAN, we detected up-regulation of TGF-beta in colocalization with Gremlin (RNA and protein), mainly in areas of tubulointerstitial fibrosis. In the same tubules, we observed decreased expression of E-cadherin and induction of vimentin and alpha-SMA. BMP-7 was significantly decreased in the CAN biopsies. In addition, HK2 stimulated with TGF-beta (1 ng/mL) induced Gremlin production at 72 hours., Conclusion: We postulated that Gremlin is a downstream mediator of TGF-beta, suggesting a role for Gremlin in EMT observed in CAN.

Cytochrome-P450 enzymes metabolize cyclosporine both in the liver and in the intestinal wall. Diltiazem, by competitive inhibition of these enzymes, may increase the absorption and the bioavailability of cyclosporine. Some evidence points to a higher activity of some specific enzymes in women, such as CYP3A, that may influence differences in cyclosporine pharmacokinetics. We examined possible gender-associated differences in pharmacokinetic profiles of cyclosporine in 19 stable renal transplant recipients cotreated with diltiazem. Ten women and nine men, chronically using diltiazem associated with cyclosporine, azathioprine, and prednisone were randomly assigned to an 8-week period of continued controlled treatment with diltiazem (10 patients) or a wash-out period discontinuing diltiazem (nine patients). At the end of this period, the time-concentration curves of cyclosporine in the first 4 hours were performed after a single dose of cyclosporine. Thereafter, a cross-over between groups was performed, and time-concentration curves repeated. A specific RIA was used to measure cyclosporine concentrations. Comparisons between male and female patients in doses of cyclosporine and other pharmacokinetics parameters (C(0), C(2), AUC(0-4)), with or without diltiazem, did not show any difference related to gender. The association of diltiazem allowed a similar degree of reduction in Neoral dosage in male and female patients (21%). No changes in serum creatinine, blood urea nitrogen, potassium, uric acid, or blood pressure, or other adverse event were observed during the study. In these groups of patients, gender was not an important factor to be considered when diltiazem is added to cyclosporine therapy.

An active regional transplantation program established in the southern region of Chile has allowed the incorporation of ethnic minorities particularly Mapuche living in this geographic area in the development of a histocompatibility database. To identify possible differences in the human leukocyte (HLA) antigen distribution in Chilean Mapuche compared with non-Mapuche, we reviewed 442 HLA tissue-typing studies. Seventy-eight of 309 recipients (25%) and 18 of 133 donors (13%) were Mapuche. Among recipients, Mapuche people showed a significantly higher frequency of the HLA antigens, A28, B16, DR4, and DR8, and a lower one for A19, B15, and DR1 (P < .05) compared with non-Mapuche individuals. A particularly higher frequency of the haplotype A28, -B16, -DR4 was also evidenced in Mapuche. Besides, these recipients showed a higher frequency of the allele -DR4 when compared with Mapuche donors. A greater frequency of some histocompatibility antigens in patients with chronic renal disease might be attributed to allelic concentration due to a high index of endogamy, but a possible association with the development of progressive renal disease cannot be ignored, especially when a higher prevalence of DR4 was observed among Mapuche recipients.

Background: Angiotensin-converting enzyme (ACE) inhibitors and angiotensin II receptor type 1 blockers (ARB) are frequently prescribed for renal transplant patients. The main reasons for their use are that their antihypertensive and antifibrogenic effects may prevent chronic renal allograft dysfunction, potentially improving transplant survival. Furthermore, ACE and ARB have been used to reduce the hematocrit in patients with posttransplant erythrocytosis. We evaluated the effects of the ARB valsartan on the evolution of hematocrit in stable renal transplant patients treated with cyclosporine (CsA), azathioprine (Aza), and prednisone., Patients and Methods: Twenty-six stable renal transplant patients treated with valsartan 80 mg/d orally were followed for 6 months. Evaluations were performed prior to as well as at 3 and 6 months following the initiation of valsartan., Results: The hematocrit levels decreased significantly at 3 months (46.1 +/- 7.3 vs 39.9 +/- 5.8 ; P < .0001) in patients with a normal hematocrit, namely a level over 38%, with no further reduction at 6 months. In recipients with an hematocrit less than 38%, there was no significant reduction, either at 3 or 6 months follow-up. Valsartan was well tolerated without significant side effects., Conclusion: We postulate that inhibition of the proerythropoietic effects of angiotensin II and/or the reduction in hypoxia within the renal tubulointerstitium as well as the vasodilator effects on the efferent arterioles, represent possible mechanisms for the reduction and stabilization of the hematocrit in stable renal transplant patients.

Background: The area-under-the-curve (AUC) of cyclosporine (CsA) reflects exposure to the drug, but this monitoring strategy is time-consuming and not cost-effective. Recently, it has been suggested that the concentration at 2 hours after dosing (C2) shows the best correlation with AUC. The C2 has been replacing the trough measurement (C0) to monitor CsA therapy, but in patients receiving diltiazem there is not much information about this issue. We investigated the correlations between C2 and C0 with absorption AUC over the first 4 hours (AUC(0-4)) in renal stable transplant patients receiving CsA therapy with or without diltiazem., Patients and Methods: Ten patients (five men) of ages 23 to 68 years and 6 to 84 months after transplantation, were randomly assigned to an 8-week initial period of either diltiazem washout or controlled treatment with diltiazem. Time-concentration curves of cyclosporine were performed at the end of this period using a specific RIA measurement of blood samples. Thereafter, a crossover of the groups was performed and after another 8 weeks, a second curve was obtained. Drugs that change the pharmacokinetics of cyclosporine or diltiazem were not allowed., Results: The cyclosporine daily dose was lower with diltiazem (173 +/- 4 mg vs 213 +/- 4 mg, P = .002), but despite a dose reduction of only 19% +/- 1.5%, there was a trend to a larger AUC/dose (28 +/- 5 ng x h/mL x mg vs 17 +/- 2 ng x h/mL x mg, P = .1) and a trend to an increased C2 when treatment included diltiazem (1035 +/- 156 ng/mL vs 652 +/- 126 ng/mL, P = NS). Moreover, we confirmed that C2 showed the best correlation with AUC(0-4), (r = 0.7, P = .04), a correlation that improved with diltiazem (r = 0.9, P < .002)., Conclusion: C2 is the point that correlates best with AUC(0-4) with or without diltiazem. C2 in the presence of diltiazem was associated with a stronger, more significant correlation with AUC(0-4).

A 28 year old man developed acute cellular rejection after renal transplantation. He received double i.v. pulses of methylprednisolone. A spontaneous rupture of the right external iliac artery occurred. Histology revealed the presence of aspergillosis. A review of the literature is included.