Principales conclusiones del Consenso Argentino de Hipertensión Arterial / Principal conclusions of the Argentine Consensus on Arterial Hypertension

El presente artículo resume los conceptos principales del Consenso Argentino de Hipertensión Arterial, realizado por primera vez en forma conjunta por las 3 principales sociedades científicas relacionadas al diagnóstico y tratamiento de la hipertensión arterial en Argentina (Sociedad Argentina de Hipertensión Arterial, Sociedad Argentina de Cardiología y Federación Argentina de Cardiología). Entre sus puntos principales se enfatiza la necesidad de mejorar el diagnóstico y control de la hipertensión arterial, la utilización de técnicas de medición ambulatoria de la presión arterial, la importancia de la estratificación de riesgo del paciente hipertenso y el uso precoz de combinaciones farmacológicas en el tratamiento como medio de alcanzar rápidamente el control. Finalmente se enumeran las principales recomendaciones del manejo de la hipertensión en poblaciones especiales como embarazadas, adultos mayores, diabéticos, hipertensos resistentes y pacientes con enfermedad renal crónica

A summary is presented in this article of the principal concepts of the Argentine Consensus on Arterial Hypertension, which has been carried out for the first time jointly by the three main scientific societies associated with the diagnosis and treatment of arterial hypertension in Argentina (Argentine Society of Arterial Hypertension, Argentine Society of Cardiology and Argentine Federation of Cardiology). Among its main points, is emphasised the need to improve the diagnosis and control of high blood pressure, the use of ambulatory blood pressure measurement techniques, the importance of the risk stratification of the hypertensive patient, and the early use of pharmacological combinations in the treatment as a means to quickly achieve control. Finally, it lists the main recommendations for the management of hypertension in special populations, such as pregnant women, elderly people, diabetics, resistant patients, as well as patients with chronic kidney disease

[Principal conclusions of the Argentine Consensus on Arterial Hypertension]. / Principales conclusiones del Consenso Argentino de Hipertensión Arterial.

A summary is presented in this article of the principal concepts of the Argentine Consensus on Arterial Hypertension, which has been carried out for the first time jointly by the three main scientific societies associated with the diagnosis and treatment of arterial hypertension in Argentina (Argentine Society of Arterial Hypertension, Argentine Society of Cardiology and Argentine Federation of Cardiology). Among its main points, is emphasised the need to improve the diagnosis and control of high blood pressure, the use of ambulatory blood pressure measurement techniques, the importance of the risk stratification of the hypertensive patient, and the early use of pharmacological combinations in the treatment as a means to quickly achieve control. Finally, it lists the main recommendations for the management of hypertension in special populations, such as pregnant women, elderly people, diabetics, resistant patients, as well as patients with chronic kidney disease.

Evaluation of TLR4 Inhibitor, T5342126, in Modulation of Ethanol-Drinking Behavior in Alcohol-Dependent Mice.

AIMS: Several lines of evidence support a critical role of TLR4 in the neuroimmune responses associated with alcohol disorders and propose inhibitors of TLR4 signaling as potential treatments for alcoholism. In this work, we investigated the effect of T5342126 compound, a selective TLR4 inhibitor, on excessive drinking and microglial activation associated with ethanol dependence. METHODS: We used 2BC-CIE (two-bottle choice-chronic ethanol intermittent vapor exposure) paradigm to induce ethanol dependence in mice. After induction of the ethanol dependence, we injected T5342126 (i.p., 57 mg/kg) for 14 days while monitoring ethanol intake by 2BC (limited access to ethanol) method. RESULTS: T5342126 decreased ethanol drinking in both ethanol-dependent and non-dependent mice but T5342126 showed also dose-dependent non-specific effects represented by decreased animal locomotor activity, saccharine intake, and body core temperature. Six days after the last ethanol-drinking session, we examined the immunohistochemical staining of Iba-1 (ionized calcium-binding adapter molecule 1), a microglial activation marker, in the central nucleus of the amygdala (CeA) and dentate gyrus (DG) of the hippocampus. Notably, T5342126 reduced Iba-1 density in the CeA of both ethanol-dependent and non-dependent mice injected with T5342126. There were no significant differences in the DG Iba-1 density among the treatment groups. CONCLUSIONS: Collectively, our data suggest that T5342126, via blocking TLR4 activation, contributes to the reduction of ethanol drinking and ethanol-induced neuroimmune responses. However, the non-specific effects of T5342126 may play a significant role in the T5342126 effects on ethanol drinking and thus, may limit its therapeutic potential for treatment of alcohol dependence. SHORT SUMMARY: T5342126, an experimental TLR4 inhibitor, is effective in reducing ethanol drinking and inhibiting the activation and proliferation of microglia in both ethanol-dependent and non-dependent mice. However, T5342126's use as a potential candidate for the treatment of alcohol addiction may be limited due to its non-specific effects.

Voiding dysfunction: another etiology of vulvovaginitis in young girls.

OBJECTIVE: To determine the prevalence of voiding dysfunction (VD) in patients with persistent vulvovaginitis (PVV), and to evaluate the clinical response of PVV in the treatment of VD. PATIENTS AND METHODS: Girls four years or older who consulted for PVV for at least one month and who did not respond to general measures. A physical examination was performed with visual inspection and colposcopy; vaginal samples for culture and vaginoscopy were carried out. On every patient urodynamic studies were performed. Girls who were diagnosed with VD were treated. A pediatric gynecologist did the follow-up; a successful response was considered when inflammatory symptoms and vaginal discharge ceased. RESULTS: Twenty patients were included, mean age 8.6 years (range: 4.6-14 years); 75% prepubertal symptoms lasted for 1.8 years; 19 (95%) had urodynamia, 10 (52.6%) had an overactive bladder, 8 (42.1%) external bladder sphincter dyssynergia, 1 (5.2%) hypotonic bladder, and 13 (65%) showed improvement. CONCLUSION: VD is an important cause when considering the etiology of PVV.

Early steroid withdrawal in pediatric renal transplantation at a single center: preliminary report.

Steroids have been a cornerstone in renal transplant immunosuppression despite cardiovascular risk and growth impairment in children. New immunosuppressive drugs have allowed early withdrawal or even complete avoidance of steroids. To evaluate a new immunosuppressive protocol with early withdrawal of steroids in a pediatric renal transplant population, we initiated a prospective study in recipients >1 year old who showed low immunologic risk was started. Group A (n = 12) received decreasing doses of steroids until day posttransplant 7 under a regimen of Tacrolimus (FK) and mycophenolate mofetil (MMF). Group B (n = 11) were controls treated with steroids, cyclosporine and azathioprine. In both groups, induction therapy included basiliximab. We evaluated anthropometric and biochemical variables, acute rejection episodes (ARE), and cytomegalovirus (CMV) infection. Mean values and variations for continuous variables were calculated at months 1 and 3 for comparison at the same time using student's t-test and regresion analysis. We obtained mean values at months 1, 3, and 6 for groups A and B of creatinine clearance (mL/min): 86.2 versus 107.4; 76.9 versus 96.6; 73.3 versus 97.9 (P < .05); hematocrit (%) was 27.4 versus 31.8; 29.3 versus 33.9; 32.9 versus 34.3% (P < .05); total cholesterol (mg/dL), 148 versus 195, 139 versus 85, 142 versus 174 (P < .05); creatinine clearance decreased in both groups during follow-up with a smaller slope among group A (P < .05). No differences were observed between the groups in Z height, diastolic and systolic blood pressures at 6 months of follow-up. Serum total cholesterol mean levels at months 1, 3, and 6 were significantly lower among the group withdrawn from steroids (P < .05). Plasma bicarbonate levels were lower among group A than B; there was no difference in blood glucose levels. No AREs and no difference in CMV infections were observed. In conclusion, early withdrawal of steroids with FK and MMF was not associated with a higher incidence of either ARE or CMV infection. Lower levels of cholesterol could imply a reduced cardiovascular risk. Longer follow-up is needed to evaluate the impact of this therapy on renal function and linear growth.

Carotid intima-media thickness as a cardiovascular risk marker in pediatric end-stage renal disease patients on dialysis and in renal transplantation.

Cardiovascular diseases are the principal cause of morbidity and mortality among young adults with chronic renal disease. Atherosclerotic structural changes as detected by high-resolution B-mode ultrasonography preceed clinical findings by several decades. The carotid intima-media thickness (cIMT) is being used as a marker of early atherosclerosis. We determined the cIMT of common carotid artery (CCA) in 8 asymptomatic children on dialysis or 12 after renal transplantation for comparison with 30 healthy controls. This prospective study of 40 children showed a mean age of 13.5 years (range, 8 to 18). We evaluated cIMT, hemoglobin, serum creatinine levels, lipid profile, and homeostasis model assessment (HOMA). The statistical analysis for variables with normal distribution was Student's t test. Parameters with a non-normal distribution were evaluated by the Mann-Whitney or Spearman correlation analysis with P < .05 considered statistically significant. The mean measurements of cIMT (mm) of both CCA were dialysis 0.450 +/- 0.042; transplant 0.467 +/- 0.033, and controls 0.380 +/- 0.009 (P < .03). The homa levels of 2.45 +/- 0.98 for dialysis and 1.8 +/- 0.62 for transplant, were both significantly higher than the control group (0.8 +/- 0.09; P < .01). The Ca x P product was higher in dialysis vs transplant group: 63.0 +/- 10.0 versus 46.2 +/- 2.2 (P < .03). The intact parathyroid hormone levels were 666.7 +/- 276.7 versus 44.2 +/- 2.8, respectively (P < .008). The low-density lipoprotein cholesterol was 129.0 +/- 23.1 versus 80.8 +/- 10.6, respectively (P < .04). The cIMT correlated with the duration of dialysis before transplantation. Changes in IMT can be detected by ultrasonography in early childhood in uremic patients. The etiology of atherosclerosis is multifactorial in children with end-stage renal disease. It seems possible to prevent or improve the factors related to cardiovascular risk in these patients.

Factors that influence nonadherence in immunosuppressant treatment in pediatric transplant recipients: a proposal for an educational strategy.

Kidney transplant is the best treatment for patients with chronic renal failure. Scientific advances have optimized immunosuppressive treatment; however, adherence to medical treatment is not always achieved. Our aims were to identify the key factors that influenced nonadherence behavior to define effective educational strategies. A qualitative study was performed through an analysis of patient/tutor questions in interviews. A quantitative analysis was applied to epidemiologic variables, time posttransplant, and percentages/frequencies of responses from the interviews. A transplant nurse, psychologist, and social worker elaborated an instrument based on seven questions related to the transplant, the risk and/or loss of the graft, events that happened as consequence of this fact, allowing interviewees to freely express their opinions. The interviews were recorded on a microcassette recorder for later transcription. The analysis was determined by categories containing the answers to each question according to frequency. Informed consent was obtained from the parent/tutor. Among 150 transplants performed from 1989 to 2006 there were 15 nonadherences among 80% interviewed subjects. The mean age was 9.7 years. Loss of the graft occurred in 50%, at 37.7 months, post-transplant from 67% deceased and 33% living donors with 25% of cases preemptive transplants. The main factors for nonadherence were lack of supervision in taking medications, numbers and fastidious schedules, family conflicts, and poor communication between parents and the medical team. In conclusion, it is necessary to modify the pattern for transplant patient care that allows the patient and family to actively participate in the medical process including a multidisciplinary group.

Pediatric renal transplantation: a single center experience over 14 years.

Between 1989 and 2003, 100 transplants were performed in 96 patients at the pediatric nephrology unit of the Calvo Mackenna Children's Hospital. Mean age 10.9 +/- 3.9 yr (1-17.6), 30% from LD. Donors were younger than 5 yr in five patients and all recipients received an 'en bloc' graft. Original disease was hypo/dysplasia 27%, reflux nephropathy 22 and 17% chronic glomerulonephritis. The immunosuppressive protocol during the first period (n = 56, 1989-2000): Cyclosporine, steroids and azathioprine, and during the second period (n = 44, 2001-2003): FK, steroids, MMF and anti-CD25 antibody (mAbs). AR was reported in 22 patients, 11% in LD, 31% in DD (p < 0.01). The AR rate decreased from 40 to 8% after anti-CD25 monoclonal induction. Patient actuarial survival rate at 1, 3 and 5 yr was 100% for LD and 96% for DD. The overall actuarial graft survival at 1,3, and 5 yr was 96.7, 96.7 and 71% for LD and 89, 76 and 73% for DD donors. Graft survival rate improved from the first period (1989-2000) to the second period (2001-2003; p = 0.05). No difference in graft survival rate with HLA-A,B,DR matching was found. Graft survival rate was better when cold ischemia time was <24 h (p < 0.01). CMV infections increased from 19 to 40% when MMF and anti-CD25 Ab were introduced (p < 0.01). The height/age Z score at 1, 3 and 5 yr post-transplant was -2.2, -2.1, -2.2, respectively, for children older than 7 yr and -1.8, -1.9, -2.1 for those transplanted younger than 7 yr of age who were switched to alternate day steroids (p < 0.01). The cause of graft lost was: chronic rejection eight, non-adherence four, AR four and vascular thrombosis two. The cause of death in two patients was fungus septicemia and accelerated rejection. Pediatric renal transplantation can be performed in our group with acceptable morbidity, low mortality and graft survival rates similar to other reports in North America and Western Europe. Graft survival rate improved with newer immunosuppression and greater experience at the center. Management of non-adherence and chronic rejection remain the major challenges.

Kt/V and nPNA in pediatric peritoneal dialysis: a clinical or a mathematical association?

The relationship between dialysis dose and nutrition is a field of particular interest in chronic pediatric dialysis (PD), and a positive correlation between ureaKt/V and nPNA has been published, suggesting a better nutritional status is associated with higher dialysis doses. However, this relationship has also been criticized as being the result of a mathematical coupling resulting from the same variables. The objective of the study was to establish the relationship between dialysis dose (Kt/V) and nutritional variables: daily protein intake (DPI), protein catabolic rate (PCR), protein equivalent of total nitrogen appearance (PNA) and nitrogen balance (NB) in dialyzed children. A cohort, prospective, observational study was carried out, for which 223 biochemical measurements were performed in 20 patients, ages 1 month to 14.3 years old (13 males), under PD for a 12-month period of follow-up. Monthly residual and total ureaKt/V, DPI, PCR, nPNA and NB were calculated, and the correlation between Kt/V and the nutritional parameters was evaluated. The Borah equation was used to calculate the nPNA. The data are reported as the mean plus or minus the standard error. All statistical comparisons were done with a paired t test, and two-way ANOVA for repeated measures was used to calculate correlations. A P <0.05 was considered significant. Mean total and residual Kt/V was 3.4+/-1.3 and 1.69+/-1.27, respectively; nPNA and PCR were 1.38+/-0.44 and 1.39+/-0.43 g/kg/day, daily protein intake (DPI) was 3.25+/-1.27 g/kg/day, and NB showed a value of 1.86+/-1.25 g/kg/day. A significant positive correlation was found between Kt/V and DPI, PCR, DPC and nPNA (all values P <0.0001), but no correlation was found between total and residual Kt/V vs. nitrogen balance ( P:ns). Total Kt/V showed a significant positive correlation with nPNA, but it did not show any correlation with nitrogen balance, suggesting that the relationship with nPNA is the result of a mathematical association calculated from the same variables.

Pediatric renal transplantation: 13 years of experience--report from the Chilean Cooperative Multicenter Group.

Between 1989 and 2002, 178 renal transplants were performed in 168 pediatric patients in Chile. The mean age was 10.9 +/- 3.7 years (range 1 to 17.9). End-state renal disease etiologies were: congenital renal hypoplasia/dysplasia, chronic glomerulonephritis, and reflux nephropathy. Seventy received a graft from a living donor (LD), and 108 from a cadaveric donor (CD). Only 9% received antibody induction. Acute rejection episodes were reported in 76 patients: 38% in LD recipients and 48% in CD recipients (P = NS). One-, 3-, and 5-year graft survivals were 88%, 84%, and 76%, respectively, for LD and 86%, 79%, and 68% for CD recipients. Actuarial graft survival was significantly better among those patients with serum creatinine < 1 mg/dL at 1 year posttransplant compared with those with creatinine > 1 mg/dL (P < .05). The graft survival rate has improved from the first period (1989 to 1996) to the second period (1997 to 2002); (P = .05). Patient survival rates at 1, 3, and 5 years were 98%, 98%, and 98%, respectively, for LD, and 95%, 94%, and 94% for CD. Global height/age Z-score decreased from -0.7 at birth to -1.5 when dialysis started, and to -2.4 at the time of transplantation. The Z-score height/age at 1, 3, and 5 years posttransplantation was -2.25, -2.24, and -2.5. No significant differences were observed in transplant outcomes comparing patients younger than 7 years with those older ones. In conclusion, pediatric renal transplant has been performed in Chile with acceptable morbidity. The patient and graft survivals are similar to the reported international experience. In the last period there was a significant improvement in graft survival.

The pharmacokinetics of enalapril in children and infants with hypertension.

Forty children with hypertension between the age of 2 months and 15 years received 0.07 to 0.14 mg/kg of enalapril as a single daily dose. Enalapril was administered orally as a novel extemporaneous suspension in children younger than 6 years of age and as tablets in older children. First-dose and steady-state pharmacokinetics were estimated in children ages 1 to 24 months, 25 months to < 6 years, 6 to < 12 years, and 12 to < 16 years. Maximum serum concentrations for enalapril occurred approximately 1 hour after administration. Serum concentrations of enalaprilat, the active metabolite of enalapril, peaked between 4 and 6 hours after the first dose and 3 and 4 hours after multiple doses. The area under the concentration versus time curve (AUC), adjusted for body surface area, did not differ between age groups. Based on comparison of first-dose and steady-state AUCs, the accumulation of enalaprilat in children ranged from 1.13- to 1.45-fold. For children ages 2 to 15 years, mean urinary recovery of total enalaprilat ranged from 58.3% in children ages 6 to < 12 years to 71.4% in children ages 12 to < 16 years. Urinary recovery for children ages 2 to < 6 years was 66.8%. The mean percentage conversion of enalapril to enalaprilat ranged from 64.7% for children ages 1 to 24 months to 74.6% for children ages 6 to < 12 years. The median effective half-life for accumulation ranged from 14.6 hours in children ages 12 to < 16 years to 16.3 hours in children ages 6 to < 12 years. There were two serious adverse events, neither of which was attributed to enalapril or resulted in discontinuation of the study drug. The extemporaneous suspension used in this study was tolerated well. The pharmacokinetics of enalapril and enalaprilat in hypertensive children ages 2 months to 15 years with normal renal function appears to be similar to that previously observed in healthy adults.

Resveratrol, a red wine constituent, is a mechanism-based inactivator of cytochrome P450 3A4.

Resveratrol, a phytoalexin found in red wine, has been shown to possess antioxidant and antimutagenic properties. Incubation of resveratrol with Sf9 insect microsomes containing baculovirus-derived human cytochrome P450 3A4 (CYP3A4) and NADPH-cytochrome P450 reductase showed that resveratrol inactivated CYP3A4 in a time- and NADPH-dependent manner. Resveratrol, erythromycin and troleandomycin inactivated CYP3A4 at a similar rate (as reflected by k(inact)) whereas the binding affinity to CYP3A4 (as reflected by K(I)) was in the order of: troleandomycin > erythromycin > resveratrol. (K(I) and k(inact) for CYP3A4 inactivation by resveratrol, erythromycin and troleandomycin are 20 microM and 0.20 min(-1), 5.3 microM and 0.12 min(-1) and 0.18 microM and 0.15 min(-1), respectively.) Fractionation studies of red wine showed that fractions that did not contain resveratrol inactivated CYP3A4 significantly. In addition, the resveratrol content in red wine used in the study was too low to account for the degree of CYP3A4 inactivation observed after red wine treatment. Inactivation studies using a variety of red wine types showed that the CYP3A4 inactivation did not correlate to their resveratrol content. In summary, data here showed that resveratrol is an effective mechanism-based inactivator of CYP3A4; however, it is not one of the main red wine constituents that are responsible for CYP3A4 inactivation by red wine. Nevertheless, inactivation of CYP3A4 by resveratrol may cause clinically relevant drug interactions with CYP3A4 substrates.

Enalapril and prednisone in children with nephrotic-range proteinuria.

The effect of enalapril and low prednisone doses on the urinary protein electrophoretic pattern was studied in 13 pediatric patients with glomerular diseases and steroid-resistant nephrotic syndrome. Enalapril was administered at doses of 0.2-0.6 mg/kg per day for 24-84 months, and prednisone was introduced 2 months later in 11 patients at doses of 30 mg/m2 on alternate days. The urine protein electrophoretic pattern showed a reduction of 80% and 70% in the total protein and albumin, respectively, after enalapril. Total urinary protein decreased from 5.46 to 1.1 g/m2 per day (P<0.001). A marked change from a pattern of non-selective urinary protein loss to an albumin-selective proteinuria was observed. Mean total plasma proteins increased from 4.7 to 5.43 g/dl (P<0.001). Four patients became free of proteinuria 24 months after enalapril was started, but only 2 remained free of proteinuria at 48 months of follow-up. The other 11 patients had persistent albuminuria of between 0.5 and 2.6 g/m2 per day with a selective urinary electrophoretic pattern. No additional decrease was observed after steroids were introduced. A clinical improvement in edema was observed in all children. Three patients developed transient acute renal failure, during the course of an infectious disease; 2 developed peritonitis and 1 pneumopathy. In these patients withdrawal of enalapril was necessary until a complete recovery of renal function was observed. Four patients were hypertensive on admission, achieving normal blood pressure 1 month after enalapril was started. No episodes of systemic arterial hypotension were seen. Creatinine clearance and serum potassium showed no statistically significant change.

[Chronic hemodialysis in children]. / Hemodiálisis crónica en pediatría.

BACKGROUND: The final objective of every children that is admitted to a program o hemodialysis of peritoneodialysis is to receive a renal graft. AIM: To report the experience in pediatric hemodialysis in two pediatric hospitals in Chile that are reference centers for renal transplantation. PATIENTS AND METHODS: Sixty patients, 55% female, aged 2 to 15 years old, admitted to the dialysis and transplant program since 1987, with a creatinine clearance of less than 20 ml/min/1.73 m2, were studied. RESULTS: Twenty percent of children were less than 5 years old at the moment of admittance to the program and 3.3% weighed less that 10 kg. Etiologies of end stage renal disease were glomerulopathies in 33.4%, reflux nephropathy in 27.7%, obstructive uropathy in 13.3%, hypoplasia/dysplasia in 10%, hereditary problems in 8.3% and vascular disorders in 5%. Eighty six percent of patients were dialyzed less than 2 years and 5% more than 4 years. Fifty percent had received prior medical treatment, 5% had been treated with intermittent peritoneal dialysis, 5% with chronic ambulatory peritoneal dialysis and 20% presented as a terminal renal failure. Sixty two percent received a renal graft, 25% is still on hemodialysis, 3.3% switched to chronic ambulatory peritoneal dialysis, 3.3% had a recovery of renal function and 6.7% died being on hemodialysis. Arterio-venous fistulae were the vascular accesses in 75% of patients, double lumen catheters in 50% and vein grafts in 5%. Malfunctioning or infections were the main complications of arterio-venous fistulae, accounting for 30% of hospital admissions. CONCLUSIONS: The availability of new vascular accesses and new hemodialysis machines specially designed for children, along with specially trained health care personnel, should reduce the mortality and complication rates of hemodialysis in this age group.

[Initial therapy of primary nephrotic syndrome in children: evaluation in a period of 18 months of two prednisone treatment schedules. Chilean Co-operative Group of Study of Nephrotic Syndrome in Children]. / Cuadro inicial del sindrome nefrósico primario del niño: evaluación a 18 meses de dos esquemas de tratamiento con prednisona. Groupo Cooperativo Chileno de Estudio del Sindrome Nefrósico del Niño.

Ninety six patients aged from 6 months to 15 years and were admitted to Chilean hospitals with the diagnosis of primary nephrotic syndrome in a period of 30 months. These patients were randomly separated in two groups, group A received prednisone for 8 weeks and group B received the same drug during 12 weeks. All patients were evaluated at 6, 12 and 18 months after the end of treatment. The moment and number of relapses per patient, accumulated percentage of relapses, relapse rate per 100 patients, total number of relapses and complications were assessed. Frequent relapsers were subjected to a kidney biopsy, leaving in the protocol only those patients that had minimal changes. Patients resistant or dependent to steroid therapy were discarded. Thus we report the results of 56 treated patients followed during 18 months. No differences in analyzed parameters were observed between the two treatment groups. It is concluded that these preliminary results do not support the prolongation of prednisone treatment in children with primary nephrotic syndrome.

Calcitriol oral pulse therapy in children with renal osteodystrophy.

A 6-month protocol of oral pulse calcitriol was used in nine uraemic children (2-14 years old) on dialysis who presented with renal osteodystrophy. Calcitriol was administered twice a week, 4 micrograms per dose for patients over 30 kg and 3 micrograms for patients less than 30 kg. Plasma levels of parathyroid hormone, calcium, phosphorus and alkaline phosphatase were carefully controlled during the study. Parathyroid hormone levels decreased by 68% and 56% by the 2nd and 6th months of treatment in seven patients, while they remained unchanged in two patients with focal segmental glomerulosclerosis and massive proteinuria. Eight hypercalcaemic episodes from 77 determinations were observed, all of them recovered after 1 week of vitamin D withdrawal. We conclude that oral calcitriol pulse therapy is a good alternative for renal osteodystrophy in uraemic children. Careful monitoring of plasma parathyroid hormone and calcium is needed during follow-up when using this approach in paediatric patients.