Graciela Vallejo

Uso del sirolimus en pacientes con síndrome nefrótico córtico-resistente primario

Persistent nephrotic syndrome that does not respond to treatment may cause progression to kidney failure. We designed a therapeutic protocol with sirolimus for this group of patients. We conducted a prospective, interventional, time series, cohort study lasting 20 months. Thirteen patients were enrolled, with a mean age of 10 years (range: 8-18 years old) with steroid-resistant primary nephrotic syndrome and a histological diagnosis of focal and segmental glomerulosclerosis. We administered sirolimus 3.6mg/m2/day. The duration of this regimen was 12 months in responsive patients. The protocols efficacy was assessed according to reduction of proteinuria (3 response levels: total, partial, or no response). Severity of histological renal damage and mean time from clinical diagnosis to protocol initiation were also assessed. Nine of 13 patients responded to the treatment with sirolimus, and mean progression time and the severity of histological renal damage influenced response to therapy. We believe that sirolimus is a valid treatment option in patients with steroid-resistant nephrotic syndrome, even though this regimen probably requires an earlier treatment.

Medición comparativa de la densidad urinaria: tira reactiva, refractómetro y densímetro

INTRODUCTION The urine specific gravity is commonly used in clinical practice to measure the renal concentration/dilution ability. Measurement can be performed by three methods: hydrometry, refractometry and reagent strips. AIM To assess the accuracy of different methods to measure urine specific gravity. METHODS We analyzed 156 consecutive urine samples of pediatric patients during April and May 2007. Urine specific gravity was measured by hydrometry (UD), refractometry (RE) and reagent strips (TR), simultaneously. Urine osmolarity was considered as the gold standard and was measured by freezing point depression. Correlation between different methods was calculated by simple linear regression. RESULTS A positive and acceptable correlation was found with osmolarity for the RE as for the UD (r= 0.81 and r= 0.86, respectively). The reagent strips presented low correlation (r= 0.46). Also, we found good correlation between measurements obtained by UD and RE (r= 0.89). Measurements obtained by TR, however, had bad correlation when compared to UD (r= 0.46). Higher values of specific gravity were observed when measured with RE with respect to UD. CONCLUSIONS Reagent strips are not reliable for measuring urine specific gravity and should not be used as an usual test. However, hydrometry and refractometry are acceptable alternatives for measuring urine specific gravity, as long as the same method is used for follow-up.

Eficacia del Enalapril en pacientes monorrenos con dieta normoproteica y sin ella

INTRODUCTION The patient with a solitary kidney and free protein intake can present pathological microalbuminuria. OBJECTIVE To evaluate the efficacy of Enalapril in patients with single kidney and with or without normoprotein diet. MATERIALS AND METHODS We studied 49 patients, mean age 11 years, eutrophics, with normal renal function and with approved medical consent. The exclusion criteria were: uropathies, arterial hypertension, malignant diseases, orthostatic proteinuria and previous treatments with nephrotoxics drugs. Patients were classified in two groups: Group A: with normoprotein diet (0.8 to 1.2 g/kg/day). Group B: with free protein intake. The patients with abnormal microalbuminuria received Enalapril (doses between 0.1-0.3 mg/kg/ day). RESULTS Group A: 21 patients, 2 with abnormal microalbuminuria. Mean increase of the renal size 14% (SD 8), risk of presenting pathological microalbuminuria: 9%. Group B: 28 patients, 11 with pathological microalbuminuria. Mean increase of the renal size: 33.8% (SD 6.1), risk of presenting abnormal microalbuminuria: 40%. RR: 4.125 (CI 1-16) (p: 0.01). NND: 3. Mean range of microalbuminuria pre- Enalapril 50 microg/min and post-Enalapril 11 microg/ min. Mean doses of Enalapril: 0.2 mg/kg/day. Correlation coefficient between increase of renal size and microalbuminuria range: 0.75 and between increase renal size and protein intake: 0.72. Mean time to reach abnormal microalbuminuria: 81 months (DS 7). CONCLUSION Enalapril together with the normoprotein diet in patient with single kidney reduces the risk of developing abnormal microalbuminuria.

Estudio comparativo entre el esquema convencional y el tratamiento prolongado con esteroides en el síndrome nefrótico cortico-sensible primario en Pediatría

BACKGROUND In the steroid-sensitive nephrotic syndrome (SSNS) the prolonged treatment with steroids could decrease the frequency of relapses. We conducted a comparative study of prolonged steroid scheme and the usual treatment of primary SSNS to assess: the number of patients with relapses, mean time to treatment initiation, to remission and to first relapse, total number of relapses, total cumulative dose of steroids, and the steroid toxicity. METHODS Patients were divided into two groups: group A (27 patients) received 16-β-methylprednisolone for 12 weeks, reducing the steroid until week 24. Group B (29 patients) received 16-β-methylprednisolone for 12 weeks and placebo until week 24. RESULTS Cumulative incidence rate of relapse (person/years) for group A was of 36/100 and 66/100 for group B (p=0.04). Average elapsed time to first relapse was of 114 days for group A and of 75 days to for group B (p=0.01). The difference in time for initial response to treatment and up to achieve remission between both groups was not significant. Total cumulative relapses were 9 for group A and 17 for group B (p=0.04). Total patients with relapses were 3 for group A and 7 for group B (p=0.17). Cumulative average dose per patient was 5,243mg/m2 for group A and 4,306mg/m2 for group B (p=0.3), and serum cortisol was 14μg/dl for group A and 16μg/dl for group B (p=0.4). There were no steroid toxicity differences between groups. CONCLUSIONS The duration of the treatment had an impact on the number of relapses without increasing steroid toxicity.