ALUMINUM-CONTAINING AGENTS MAY BE TOXIC IN PREDIALYSIS CHRONIC RENAL-INSUFFICIENCY PATIENTS

Objective. To investigate the possible toxic effects of long-term low dose aluminium (Al) exposure in predialysis chronic renal insufficienc y (CRI) patients (serum creatinine >1.4 mg dL(-1)). Design. An open, r andom, and prospective clinical study. Setting. The study was carried out at Chang Gung Memorial Hospital, a medical centre of Chang Gung Me dical College. Subjects. Seventy CRI patients who have regularly atten ded a nephrology out-patient department participated in this study. Af ter a 3-month wash-out period 50 were given an Al loading test and 20 received no Al-containing agents. Interventions. We used a low dose of AI(OH)(3) (one tablet three times day(-1), about 302 mg aluminium day (-1)) for 3 months as an Al loading test. Main outcome measures. The s tudy was divided into two phases: phase 1, a basal study to measure se rum Al, iron, ferritin, daily urinary Al excretion and renal function status; and phase 2, in which an Al loading test was performed. The ph ase 1 parameters were measured again after the Al loading test to comp are the differences between pre- and post-study in the two groups. Res ults. We found significant increments of serum Al and daily urinary Al excretion in all study group patients after the Al loading test. The increments of serum Al correlated with basal creatinine clearance (Ccr : r=-0.352, P <0.05) and basal serum ferritin (r=-0.302, P <0.05). Ser um ferritin was significantly reduced after the Al loading tests, and the reduction (r=0.357, P <0.05) positively correlated with the increm ents of daily urinary Al excretion in the study group patients, Howeve r, no significant changes of serum Al, ferritin, and daily urinary Al excretion were noted in the control group patients. Conclusions. A lon g-term low dose Al exposure can cause significant Al accumulation and iron store depletion in CRI patients. Therefore, Al-containing agents should be used with caution in patients with CRI.