You are correct. Serum fluoride level was elevated to >10 times the upper limit of normal. Compressed gas dusters used to clean electronics commonly contain fluorocarbons, and abuse is an increasingly recognized cause of fluoride toxicity. Skeletal fluorosis is a metabolic bone dz caused by excess fluoride intake. Swollen hands with underlying symmetric periosteal hyperostosis are a common manifestation and can develop rapidly. The patient continued to abuse up to 24 cans of duster daily over the next year. Repeat hand X-ray 14 months later showed progression of periosteal new bone formation at the phalanges and metacarpal bones. Eventually, he sought inpatient tx and has abstained from inhalant abuse for several months. The clinical and radiographic manifestations of skeletal fluorosis may be slowly reversible over years to decades after cessation of fluoride intake.

BMJ Case Reports CP 2020;13:e233954.