Renal disease in chronic arthritis of childhood. A study of urinary N-acetyl-beta-glucosaminidase and beta 2-microglobulin excretion.
Urinalyses of randomly obtained samples from children with various types of chronic arthritis revealed proteinuria in 2.3% of patients, hemoglobinuria in 3.5%, erythrocyturia in 4.1%, and leukocyturia in 5.3%; these frequencies are within the range found by screening school children. However, raised urinary levels of N-acetyl-beta-glucosaminidase and/or beta 2-microglobulin (both sensitive measures of renal tubular damage) were found more frequently in children with chronic arthritis than in controls (P less than 0.0001). Abnormalities of either N-acetyl-beta-glucosaminidase or beta 2-microglobulin excretion were associated with active arthritis as measured by physician global estimate of disease activity, with a polyarticular onset of juvenile rheumatoid arthritis, and with the use of slow-acting antirheumatic drugs or the concurrent use of more than 1 nonsteroidal antiinflamtory drug. Abnormal renal tubular function appears to be common in chronic arthritis of childhood. The long-term consequences of this abnormality remain to be elucidated.
Malleson
P N
PN
Department of Pediatrics, University of British Columbia; Vancouver, Canada.
Lockitch
G
G
Mackinnon
M
M
Mahy
M
M
Petty
R E
RE
D000118:Acetylglucosaminidase / Q000652:urine*; D000293:Adolescent; D000328:Adult; D001168:Arthritis / Q000150:complications* / Q000201:enzymology / Q000652:urine; D015415:Biomarkers; D002648:Child; D002675:Child, Preschool; D002908:Chronic Disease; D003401:Creatine / Q000652:urine; D005260:Female; D006801:Humans; D015994:Incidence; D007674:Kidney Diseases / Q000150:complications* / Q000201:enzymology / Q000652:urine; D008297:Male; D001613:beta 2-Microglobulin / Q000652:urine*
D015415:Biomarkers; D001613:beta 2-Microglobulin; D000118:Acetylglucosaminidase; D003401:Creatine