[Diagnosis and classification of tubulointerstitial nephritis]

To make a correct diagnosis of tubulointerstitial nephritis and to make it in time calls for knowledge of its clinical symptomatology (it is usually very marked in acute forms and in chronic forms it is frequently inapparent) and it is essential to know the main causes which produce this type of renal damage. In some instances the already developed disease is diagnosed and not infrequently even renal failure. Recognition of the aetiological and pathogenetic multiplicity of the disease, as made possible by the submitted classification of the WHO expert commission, is one of the prerequisites of the diagnosis and treatment in time or of prevention by effective provisions.