Kidney- and serum derived proteins in urine of patients suffering from renal diseases or arterial hypertension.
Excretion patterns of kidney related urinary proteins such as lysosomal beta-N-acetylglucosaminidase (beta NAG), brush-border Ala-(Leu-Gly)-aminopeptidase (AAP), gamma-glutamyl transpeptidase (GGT), and alkaline phosphatase (AP) as well as of IgG, albumin, and alpha-1-microglobulin, were assessed in patients with chronic glomerulonephritis (n = 53), pyelonephritis (n = 27), systemic lupus erythematodes (n = 5), and patients with essential arterial hypertension (n = 18). Excretion of tubular marker enzymes and serumproteins (related to urine creatinine concentration = protein creatinine index) in spontaneously voided second morning urine was significantly higher as compared to the controls (n = 2). Alpha-1-microglobulin was markedly elevated in both pyelonephritis and glomerulonephritis indicating disturbance in tubulointerstitial handling of microglobulins also in cases with primary glomerulopathy. Rise of albumin, IgG, and alpha-1-microglobulin as well as of tubular kidney markers AAP, AP, GGT, and beta NAG in cases with arterial hypertension without preexisting nephropathy support the hypothesis of a defect in charge and size permselectivity in these patients which is probably due to an increase in glomerular capillary perfusion pressure and hyperfiltration.