Risk of Fluorosis in a Patient Treated with Fluoride for Otosclerosis

M.S. PARISI; A BAGUR; B OLIVERI

Minneapolis

Congreso; 25th Anual Meeting ASBMR; 2003

American Society for Bone and Mineral Research

Since 1967 fluoride therapy has been used to arrest the progression of hearing loss inpatients with cochlear otosclerosis. Long-term fluoride ingestion has been associated witha high incidence of dyspeptic symptoms. We describe the case of a 71 year old man whodeveloped signs of fluorosis after 4 years of fluoride treatment, without receiving calciumsupplement, for otosclerosis.On presentation the patient presented high levels of alkaline phosphatase (ALP). Heunderwent surgical excision of prostatic adenoma 6 years prior to consultation. He wasreceiving 18mg/day of fluoride for treatment of Otosclerosis. Mean dietary calcium intakewas about 500mg. No calcium supplement was administered. Laboratory tests revealedhigh levels of ALP(310UI/L, normal value: 68-240), bone ALP (BALP), urinary crosslaps(uCTX) and osteocalcin (BGP). Determination of prostatic specific antigen, testosterone,thyroid hormones and other parameters of bone mineral metabolism were normal. Bonescintigraphy showed an unspecific pattern. Plain radiographs evidenced coarsetrabeculations. Lumbar spine BMD (LUNAR-DXA) was 1.178g/cm2 (t-score: -0.5, z-score:0.0) and total skeleton BMD was 1.066g/cm2 (t-score: -1.9, z-score: -1.4). One month laterthe patient suffered a traumatic fracture of the tibia. Bone biopsy could not be performed.Immediate interruption of fluoride administration was indicated. Laboratory tests performed6 months after interrupting fluoride treatment revealed normalization of laboratory test ofbone metabolism.This case report draws attention to the risk of fluorosis in patients treated with fluoridecompounds without adequate calcium association.Normal valueBALP (UI/L)31-95uCTX (ug/mmolCr)10-400BGP (ng/ml )11-46At presentation 145 1240 766 months after fluoride interruption 78 467 42