From the Guidelines
Serum aluminum levels should be interpreted with caution, as levels above 60 μg/L are considered potentially toxic, and clinical correlation is necessary to determine the risk of aluminum toxicity. The normal serum aluminum level is typically less than 10 μg/L, with levels above 60 μg/L considered potentially toxic 1. For accurate results, blood should be collected in trace element-free tubes, avoiding contamination from rubber stoppers or aluminum-containing anticoagulants. Testing should be performed before dialysis sessions in renal patients and at least 5-7 days after stopping aluminum-containing medications.
Key Considerations
- Interpretation requires clinical correlation, as serum levels reflect recent exposure rather than total body burden.
- Elevated levels may indicate toxicity, which can manifest as encephalopathy, bone disease, or microcytic anemia.
- Treatment of aluminum toxicity involves removing the source of exposure and may include chelation therapy with deferoxamine at 5-10 mg/kg/week in dialysis patients, as recommended by the K/DOQI clinical practice guidelines for bone metabolism and disease in chronic kidney disease 1.
Diagnostic Approach
- A deferoxamine (DFO) test should be performed if there are elevated serum aluminum levels (60 to 200 μg/L); clinical signs and symptoms of aluminum toxicity, or prior to parathyroid surgery if the patient has had aluminum exposure 1.
- The test is done by infusing 5 mg/kg of DFO during the last hour of the dialysis session with a serum aluminum measured before DFO infusion and 2 days later, before the next dialysis session 1.
Prevention and Monitoring
- Prevention of aluminum toxicity is preferable to use of toxic methods for treatment, particularly with the mortality of the neurological disorders and high morbidity of the bone disease 1.
- Periodic monitoring of plasma aluminum levels and assessment of aluminum in dialysate are essential for its prevention 1.
From the FDA Drug Label
In patients with aluminum-related encephalopathy and receiving dialysis, deferoxamine mesylate may cause neurological dysfunction (seizures), possibly due to an acute increase in circulating aluminum Treatment with deferoxamine mesylate in the presence of aluminum overload may result in decreased serum calcium and aggravation of hyperparathyroidism.
The serum aluminum level is not directly stated in the provided drug label. However, it is mentioned that treatment with deferoxamine mesylate in the presence of aluminum overload may cause an acute increase in circulating aluminum, and possibly lead to neurological dysfunction or decreased serum calcium. 2
From the Research
Serum Aluminum Levels
The serum aluminum level can vary depending on several factors, including the patient's exposure to aluminum and the presence of aluminum overload.
- In patients with aluminum overload, serum aluminum levels can range from 20 microg/L to over 300 microg/L 3, 4.
- In one study, patients with acutely aluminum-intoxicated haemodialysis patients had post-DFO serum aluminum levels > 300 micrograms/litre 4.
- In another study, the mean serum aluminum concentration decreased from 407.3 micrograms/l to 184.2 micrograms/l within 3 years of treatment with deferoxamine (DFO) 5.
- A study found that serum aluminum concentrations before treatment were 5-125 micrograms/ml in dialysis patients with low exposure to aluminum 6.
Diagnostic Thresholds
Certain serum aluminum levels are used as diagnostic thresholds for aluminum toxicity.
- A serum aluminum level of >or=20 microg/L is considered indicative of aluminum overload 3.
- A post-DFO serum aluminum level > 300 micrograms/litre is associated with an increased risk of neurological/ophthalmological side-effects 4.
- A serum aluminum concentration of higher than 200 micrograms/L is considered an indication for DFO therapy 7.
Treatment Effects
Treatment with deferoxamine (DFO) can affect serum aluminum levels.