According to the heterogenous nature of hemolityc uremic syndrome in relation to the etiology, pathophisiology, treatmente and diagnosis, we wich to draw attention to the main characteristics about its epidemiological clinical and immunopathological aspects. The HUS's distributes through all the world, but in Argentina, North oÊ urope, South Africa and west of USA the incidence is higher than the rest of the counties. The immune-pathological studies shows thrombotic angiopatic lesion, consisting ir generalized alte'ation of the capilar and arteriolar epithelium. Decreased levels OT PGI 2 , Von Willebrand's factor and bacterial toxins are apparently involved among mechanism that are able to produce HUS. Dial'sis is one of the main helps in the treatment of HUS, and in spite of our continued advances in knowledge about this disease, still 'urther developments are needed in pathophisiology and therapeutics to enlight its intimate mechanisms.(Key words: haemolityc uremic syndrome).El sindrome hemolitico uremico (SHU) resulta de la accion de numerosos factores etiologicos y patogenicos. En la decada del 50 Gasser y col. sistematizaron la informacion existente sobre este problema y acufiaron el terrain o de SHU 1 ' 8 .La informacidn reciente ha aclarado considerablemente la naturaleza del cuadro. En la actualidad se observa aumento de su incidencia y expansion a niveles etarios de adolescentes, adultos y ancianos 9 ' 11 , por lo tanto, el pediatra, el internista y el geriatra deben familiarizarse con el SHU. Este escrito enfoca algunos aspectos etiologicos, patogenicos y terapeuticos de relevancia clinica practica del smdrome, cuyas consecuencias pueden ser devastadoras. El tema ha sido evaluado en forma exhaustiva en otras publicaciones 2 ' 6 > 12 > 17 > 57 . Caracterfsticas clinicas y epidemiologicasEl SHU puede ocurrir a cualquiera edad, es precedido generalmente por infeccion respira-