Renal tubular function in patients receiving anticonvulsant therapy: a long-term study.
OBJECTIVE
The goal of the study was to evaluate the tubular renal function in children and adolescents who are undergoing monotherapy with sodium valproate (VPA), carbamazepine (CBZ), and phenobarbital (PB).


METHODS
The urinary excretion of N-acetyl-beta-glucosaminidase (NAG), beta-galactosidase (beta-Gal), alanine-amino-peptidase (AAP), and alpha1-microglobulin (alpha1M) was measured in 58 epileptic patients (29 girls and 29 boys), aged 12.6 +/- 3.9 years, who were subdivided into three groups according to their therapy. Fifty healthy sex-and age-matched children served as controls. The measurements were taken before the beginning of therapy and after 6 months, 1 year, and 2 years of therapy.


RESULTS
Before the beginning of therapy, there were no significant differences in NAG, beta-Gal, AAP, and alpha1M values between the control group and the three groups of epileptic children. After 6 months of therapy, patients treated with VPA and CBZ showed a significant increase in the urinary excretion of NAG and beta-Gal compared with baseline data and control values. After 1 and 2 years, these patients showed a persistence of the changes found after 6 months of therapy. In patients treated with PB, we did not find any significant variation in NAG, beta-Gal, AAP, and alpha1M urinary excretion.


CONCLUSIONS
Our study demonstrates that in patients treated with VPA and CBZ, an impairment of tubular function can be present, whereas PB does not cause any significant change.
Verrotti
A
A
Department of Medicine, Section of Pediatrics, University of Chieti, Chieti, Italy.
Greco
R
R
Pascarella
R
R
Matera
V
V
Morgese
G
G
Chiarelli
F
F
D000293:Adolescent; D000367:Age Factors; D000927:Anticonvulsants / Q000009:adverse effects / Q000627:therapeutic use*; D002220:Carbamazepine / Q000009:adverse effects* / Q000627:therapeutic use; D002648:Child; D004827:Epilepsy / Q000188:drug therapy*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007674:Kidney Diseases / Q000139:chemically induced* / Q000503:physiopathology; D007677:Kidney Function Tests; D007684:Kidney Tubules / Q000187:drug effects* / Q000503:physiopathology; D008137:Longitudinal Studies; D008297:Male; D010634:Phenobarbital / Q000009:adverse effects* / Q000627:therapeutic use; D014635:Valproic Acid / Q000009:adverse effects* / Q000627:therapeutic use
D000927:Anticonvulsants; D002220:Carbamazepine; D014635:Valproic Acid; D010634:Phenobarbital