Thallium toxicity
(Redirected from Thallium)
Background
- Soft metal used in jewelry and semiconductors
- No longer used as a rodenticide in the US
- Quickly oxidizes with exposure to air
Mechanism of Toxicity
- Unknown: seems to affect various enzyme systems
- Lethal dose 12-15 mg/kg
Clinical Features
Acute
- 12 hours: Abdominal pain, nausea, vomiting, diarrhea, shock
- 2-3 days: delirium, respiratory failure, seizures, death
Chronic
- 2-4 weeks: peripheral neuropathy, chorea, stomatitis, hair loss
Differential Diagnosis
Heavy metal toxicity
- Aluminum toxicity
- Antimony toxicity
- Arsenic toxicity
- Barium toxicity
- Bismuth toxicity
- Cadmium toxicity
- Chromium toxicity
- Cobalt toxicity
- Copper toxicity
- Gold toxicity
- Iron toxicity
- Lead toxicity
- Lithium toxicity
- Manganese toxicity
- Mercury toxicity
- Nickel toxicity
- Phosphorus toxicity
- Platinum toxicity
- Selenium toxicity
- Silver toxicity
- Thallium toxicity
- Tin toxicity
- Zinc toxicity
Evaluation
- Urine thallium concentration >20mcg/L indicates toxicity
- Blood levels are not considered reliable except in large exposures
- Plain films may be useful in acute ingestion because thallium is radiopaque
Management
- Prussian blue is mainstay of therapy
- Crystal lattice structure binds thallium ions, preventing enterohepatic recycling
- Activated charcoal binds thallium in vitro