RESUMENNormalmente, la ingesta de carga proteica aumenta el filtrado glomerular, lo que implica reserva funcional renal. Cuando disminuye el número de nefronas pueden observarse filtrados glomerulares normales por hiperfiltración, lo que implica pérdida de reserva funcional, temprano indicador de daño renal y, probablemente, factor contribuyente a su progresión. Determinamos el filtrado glomerular mediante la curva de desaparición plasmática del ácido dietilen-triamino-pentaacé-tico marcado con tecnecio-99m, en pacientes con proteinuria y depuración de creatinina normal, que padecieron síndrome urémico-hemolítico con antelación mayor de 1 año. En 33 niños, de 2-16 años de edad, se determinó la reserva funcional renal mediante filtrado glomerular basal y tras carga proteica. Considerando normal un aumento superior al 20%, 16 pacientes mostraron no tener reserva funcional renal. Esta prueba, por su seguridad y fácil realización, resulta particularmente útil en pacientes que necesitan especial control y tratamiento. Palabras clave: síndrome urémico-hemolítico, reserva funcional renal, depuración 99mTc-DTPA.
SUMMARYProtein loads in normal subjects increase glomerular filtration rate (GFR), which implies a renal functional reserve (RFR). Patients who have suffered a loss in the number of nephrons may show normal values of GFR due to hyperfiltration of remnant nephrons, with subsequent loss of RFR. This could be an early sign of renal damage, and probably a contributory factor to renal damage progress. The objective of this study is to determine the RFR through technetium-99m diethylene-triamine-penta-acetic acid (99m Tc-DTPA) clearance in patients who have recovered from hemolytic uremic syndrome.Renal functional reserve was determined in 33 children from 2 to 16 years old, with normal values of proteinuria, serum creatinine and creatinine clearance after over a year of having suffered hemolitic uremic syndrome. For that purpose 99m Tc-DTPA clearance was determined in basal condition and following protein load. In 17 patients DTPA clearance increased 20% or more after protein load compared to basal condition, and they were considered to have normal RFR, a probably index of totally recovered renal function; in the remaining 16 patients the increases were lower than 20%, and were considered to have no RFR, condition that was postulated as a contributing factor to renal damage progress. There was not significant diferences either in age or basal GFR between both groups. Being the test easier than inuline clearance and more accurate than creatinine clearance, it proves particularly useful for early diagnosis of patients that need special follow-up and treatment.
INTRODUCCIÓNEn sujetos normales, luego de la ingesta de una carga proteica existe un incremento del filtrado glomerular (FG), lo que implica la existencia de una reserva funcional renal (RFR), definida como la diferencia entre el FG estimulado y el FG basal.En pacientes que por su enfermedad renal tienen disminución del número de nefronas, el FG puede ser normal...
