The prognosis of
primary hyperoxaluria (PH) is not only related to endogenous
oxalate production and the response (if any) to
pyridoxine (in type I), but is greatly influenced by extrarenal factors like
dehydration. The earlier the diagnosis of PH, the better the chances of improving the prognosis in individual patients. Measures to enhance the solubility of
calcium oxalate are important. Besides ensuring at all times a generous fluid intake (> 2 l/m2), administration of
alkali citrate (0.15 g/kg), which has not been advocated so far in PH, appears very promising. We studied the effect of
sodium citrate in six patients with PH. Mean urinary
citrate excretion (mmol/day per 1.73 m2) without oral
citrate was very low (0.57) and rose to 2.49 with
citrate administration. This was accompanied by a significant decrease in the
calcium oxalate saturation (calculated by equil 2) from 11.7 to 6.9 (P < 0.05). Treatment in five patients over 10-36 months resulted in improved (1) or stabilized (4) renal function and reduced passage of stones. Additional measures include restriction of
salt and of
oxalate-rich food. We conclude that long-term administration of
alkali citrate is beneficial in patients with PH.