Response to a Physiologic Dose of Pyridoxine in Type I Primary Hyperoxaluria

Abstract

We measured urinary oxalate and glycolate excretion before and during pyridoxine administration (2 to 200 mg per day) in four patients with primary hyperoxaluria. In two patients with type I primary hyperoxaluria, urinary oxalate and glycolate excretion fell markedly in response to a physiologic dose of pyridoxine of 2 mg per day and became completely normal when the dose was increased to 25 mg per day. In the other two patients, who had a different type of primary hyperoxaluria (normal urinary glycolate excretion), there was no response to 2 mg of pyridoxine per day. In one of these patients, doses of 25 and 50 mg per day were also ineffective, but a moderate reduction in oxalate excretion took place with 200 mg per day; in the other patient there was a moderate reduction in oxalate excretion with 25 mg of pyridoxine per day. Our findings suggest that the degree of hyperoxaluria in this disorder may be only slight or moderate if the patient has been ingesting a pyridoxine-rich diet or multivitamin tablets containing small amounts of pyridoxine. Our results also suggest that smaller doses of pyridoxine than those heretofore employed should be tried in patients with primary hyperoxaluria.

Primary Hyperoxaluria Type I and Urolithiasis in Children: Report of Three Cases

“…Vitamin B 6 catalyzes the AGT and may therefore increase the enzyme activity when the patients are drug sensible. 10 The necessary dosage varies between 20-600 mg/day and therapeutic success can be seen when oxalate excretion decreases. 10 Supportive therapy with alkali citrates is essential in the treatment of primary hyperoxaluria, as this drug is a potent inhibitor of calcium-oxalate crystallization.…”

“…10 The necessary dosage varies between 20-600 mg/day and therapeutic success can be seen when oxalate excretion decreases. 10 Supportive therapy with alkali citrates is essential in the treatment of primary hyperoxaluria, as this drug is a potent inhibitor of calcium-oxalate crystallization. 5 Sodium or sodium-potassium citrate in a dosage of 0.1-0.15 mg/kg body weight/d (0.3-0.5 mmol/kg/d) are administered.…”

“…Vitamin B 6 catalyzes the AGT and may therefore increase the enzyme activity when the patients are drug sensible. 10 The necessary dosage varies between 20-600 mg/day and therapeutic success can be seen when oxalate excretion decreases.10 Supportive therapy with alkali citrates is essential in the treatment of primary hyperoxaluria, as this drug is a potent inhibitor of calcium-oxalate crystallization.5 Sodium or sodium-potassium citrate in a dosage of 0.1-0.15 mg/kg body weight/d (0.3-0.5 mmol/kg/d) are administered. 5 The positive effect of citrate administration was shown in a long-term study by Leumann et al in 1993.…”

“…Vitamin B 6 catalyzes the AGT and may therefore increase the enzyme activity when the patients are drug sensible. 10 The necessary dosage varies between 20-600 mg/day and therapeutic success can be seen when oxalate excretion decreases.…”

Electrogenic proton-regulated oxalate/chloride exchange by lobster hepatopancreatic brush-border membrane vesicles

“…A number of Ox 2-transport mechanisms for epithelial membranes have been proposed and include anion exchange (Gerencser et al, 1995;Hagenbuch et al, 1985;Shiu-Ming and Aronson, 1988;Talor et al, 1987), conductive transport (Freel et al, 1998;Hatch et al, 1994) and paracellular diffusion (Hatch et al, 1984(Hatch et al, , 1994. These processes contribute to transepithelial regulation of Ox 2-, which may affect the physiology or pathophysiology of the animal (Binder, 1974;Earnest, 1974;Gerencser et al, 2000;Yendt and Cohanim, 1985).…”