[Prevalence of posttransplant hypertension in pediatric kidney transplant recipients: effect on long term allograft survival]. / Prevalencia de la hipertensión arterial postrasplante renal en receptores pediátricos: Efecto en la supervivencia del injerto a largo plazo.

BACKGROUND: Arterial hypertension after renal transplantation has been identified as an adverse factor over the long term allograft function, thus identification and treatment of this entity has an impact on graft survival, as in patient survival. Studies about pediatric receptor populations have reported a prevalence of hypertension after renal transplantation ranging from 58 to 90%. In Mexico, the pre-valence of arterial hypertension after renal transplantation has been reported as 71% for an adult population attending a main hospital center in Mexico. No pediatric receptor studies in Mexico have reported the prevalence of hypertension after renal transplantation so far. The purpose of our study was to document the prevalence of arterial hypertension after renal transplantation in pediatric receptors, as well as its impact on allograft survival on a long term basis. MATERIAL AND METHODS: We performed a retrospective analysis among pediatric patients who underwent renal transplantation at our center, Centenario Hospital Miguel Hidalgo, between years 2000 to 2006. RESULTS: A total of 111 pediatric renal transplantation receptors were included, among whom 56 patients were classified as hypertensive (HT) and 54 patients were classified as nomotensive (NT) (one patient had to be excluded due to early allograft dysfunction). The mean age at the time of transplantation for the population under study was 14 +/- 3 years, with a predominance of male gender over females (1.5:1). In 89% of the transplantations, the source of the allograft was a living donor. The prevalence of arterial hypertension after renal transplantation in our population was 50.5%. Among patients in the HT group at least an episode of acute rejection presented in 8.9% (n=5) of the cases, compared to only 3.7% (n=2) of patients in the NT group with an episode of acute rejection. Likewise, the prevalence of chronic allograft nephropathy detected in the HT group was 11% (n=6) vs. 7% (n=4) in the NT group. The mean serum creatinine levels were 1.0 +/- 0.4 mg/dL for the HT group and 0.9 +/- 0.3 mg/dL for the NT group at the first month followup, however mean serum creatinine levels addressed at the last consult were different among groups: 1.7 +/- 1.8 mg/dL for the HT group versus 1.1 +/- 0.5 mg/dL for the NT group. Patient survival was similar for both groups (98%) and the follow-up period was also similar, being 39 +/- 12 months for the HT group and 39 +/- 17 months for the NT group. The multivariate Cox proportional hazard analysis demonstrated that the number of antihypertensive drugs needed to achieve the control of blood pressure, and the presence of chronic allograft nephropathy, were the independent risk factors associated to a graft loss at long term. CONCLUSION: The prevalence of hypertension after renal transplantation in our pediatric population was 50.5%, which is clearly towards the inferior limit of the reported prevalence in other studies (50-90%). The tight control of blood pressure is an intervention that may have a significant impact on graft survival at long term. In our study, the severity of arterial hypertension after renal transplantation represented as the number of antihypertensive drugs needed to achieve control of blood pressure, as well as the presence of chronic allograft nephropathy, were the factors associated to long term graft loss.

Prognostic factors in children with membranoproliferative glomerulonephritis type I.

The clinical outcome of patients with membranoproliferative glomerulonephritis (MPGN) varies, with some patients progressing to end-stage renal disease. The aim of this retrospective study was to analyze the initial clinical signs and laboratory test results associated with an MPGN prognosis. The study cohort consisted of 47 patients with idiopathic MPGN Type I treated at the National Institute of Pediatrics, Mexico City, between 1971 and 2001. The median follow-up was 3 years. The three different outcomes of interest were death, renal failure, and nephrotic syndrome. The patients' ages ranged between 4 and 16 years. All patients had different degrees of proteinuria, hyperlipidemia, and microscopic/macroscopic hematuria, and 85.1% of them showed hypocomplementemia. Clinical outcomes varied, however, the most common was nephrotic syndrome, either alone or combined with other syndromes, which accounted for 74.5% of all cases. Fifteen patients died. Treatment with methylprednisolone improved the patient's condition, while the use of chloroquine or cyclophosphamide worsened it. Twenty-two patients had some degree of renal failure; glomerular filtration rate (GFR) levels and albumin values were negatively associated to renal failure, while treatment with methylprednisolone decreased the probability of renal failure. Nephrotic syndrome persisted in 18 patients; hemolytic complement and hemoglobin values were negatively associated with nephrotic syndrome, while macroscopic hematuria was positively associated with it. Signs that suggested a poor prognosis during diagnosis were low GFR, low albumin, low hemolytic complement, and macroscopic hematuria. Treatment with methylprednisolone seemed to improve prognosis, however, this needs to be confirmed with randomized studies.