[Value of the assay of 4 urinary enzyme activities in the diagnosis of the infectious or toxic (aminoglycosides) origin of a renal disease. Preliminary results]. / Etude de la valeur des dosages de quatre activités enzymatiques urinaires dans le diagnostic de l'origine infectieuse ou toxique (aminosides) d'une atteinte rénale. Résultats préliminaires.

Occurrence of a renal failure in an infected patient may be referred to various causes: infection, renal toxicity of drugs (for instance aminoglycosides), shock . . . Determination of some urinary enzymatic activities might be helpful in unravelling the mechanism involved in such cases. Therefore a prospective study of the specificity of some urinary enzymatic activities was performed. The whole LDH activity, the LDH isoenzyme 5 (LDH 5), and two lysosomal enzymes, N-acetyl-beta-D-glucosaminidase (NAG) and beta-glucuronidase (beta-GLU) were dosed systematically, in several groups of patients: I (n = 34): healthy control, with normal renal function; II (n = 24): renal impairment, without recent upper urinary-tract infection (UTI) or aminoglycoside treatment; III (n = 27): upper UTI without aminoglycoside treatment, IV (n = 22): patients treated with aminoglycosides (without upper UTI); V (n = 16): upper UTI treated with aminoglycosides. Results showed a rather good specificity of whole LDH and LDH 5 for infectious kidney damage, and of NAG for tubular injury due to aminoglycoside treatments. Values of urinary beta-glucuronidase varied over a wide range; they were little increased in group III, without a great discriminative value. No significant difference was noted between group I and group II, for any enzyme whatever.