Indications:
(1) elevated serum aluminum levels (>= 30 µg/L)
(2) presence of clinical symptoms compatible with aluminum intoxication
If the serum level is high (this level varies with different authors), then it may not be necessary to perform the test to diagnose aluminum intoxication.
If the patient has a serum level < 30 µg/L and no symptoms, then the test may not be necessary.
Dose of deferoxamine mesylate in 200 mL of isotonic saline:
(1) 2 grams
(2) 40-50 mg/kg body weight
Procedure:
(1) The patient should not be receiving aluminum-containing compounds (antacids, phosphate binding agents, etc.) prior to or during the test.
(2) Measure aluminum in a baseline serum sample.
(3) Administer the dose of DFO slowly as a venous infusion. If on dialysis, this may be done during the final 30 minutes of the dialysis. Alternatively, it can be infused over 2 hours.
(4) Test the serum for aluminum levels 24-48 hours after the infusion. If on dialysis, this typically is done just before the next dialysis session.
change in serum aluminum level =
= (post-infusion serum aluminum level in µg/L) – (pre-infusion serum aluminum level in µg/L)
Interpretation:
• Different criteria for a positive test are used by different authors.
• Ellenhorn uses an increase > 100 µg/L for a positive test.
• Milliner et al used an increase > 200 µg/L to identify patients with aluminum-related osteodystrophy.
Adverse effects:
(1) Some patients exposed to DFO may develop deterioration in mental status, blindness or other neurological sequelae, ascribed to mobilization of aluminum.
(2) Visser and Van de Vyver recommended giving a small infusion dose (<= 500 mg) of DFO to detect patients who might develop a serious sequelae to the infusion.
(3) Isoniazid therapy may minimize the adverse effects. It serves as an MAO inhibitor (Ellenhorn, page 1536).
(4) Anaphylaxis may occur and appropriate medications should be available during and after the infusion.
