SUN-801 - Tea-Induced Skeletal Fluorosis Mimicking Metabolic Bone Disease in A Middle-Aged Woman

Introduction:
Skeletal fluorosis is an uncommon condition in the United States and is rarely considered in the differential diagnosis of bone pain and abnormal mineral metabolism. Chronic ingestion of high-fluoride beverages, including certain teas, can lead to progressive osteosclerosis and mimic hyperparathyroidism or other metabolic bone disorders. We present a case of tea-induced skeletal fluorosis in a woman with long-standing diffuse bone pain and markedly elevated bone density.

Case Presentation:
A 48-year-old woman with no significant medical history presented with years of progressive back pain, lower-extremity stiffness, and limited mobility. She reported consuming 1–2 gallons of brewed black tea daily for 20 years. She denied any history of inhalant or propellant abuse. Physical examination revealed kyphotic posture and reduced spinal flexibility. Laboratory evaluation showed normal calcium and normal vitamin D with mildly elevated alkaline phosphatase (175 U/L), and high-normal PTH (65 pg/mL). Serum fluoride was markedly elevated at 45.9 μmol/L. DEXA scan demonstrated a lumbar spine T-score of +5.2, and radiographs revealed diffuse osteosclerosis. Extensive workup for hyperparathyroidism, Paget disease, osteopetrosis, and hematologic disorders was negative. A diagnosis of skeletal fluorosis secondary to high-fluoride tea consumption was established. The patient was counseled to discontinue tea intake; at three-month follow-up, she reported symptomatic improvement with serum fluoride declining to 21 μmol/L

Discussion:
Skeletal fluorosis is rare in developed countries but may occur with chronic ingestion of high-fluoride beverages such as black tea, which can contain 1–9 mg/L of fluoride depending on leaf quality and preparation. The condition can resemble hyperparathyroidism, Paget disease, osteopetrosis, or diffuse idiopathic skeletal hyperostosis, complicating diagnosis. Recognition requires a detailed dietary history, radiographic evaluation, and measurement of fluoride exposure3. Early identification is crucial, as cessation of fluoride intake can halt progression and improve symptoms.
Teaching Points:
• Skeletal fluorosis can mimic metabolic bone disease and lead to misdiagnosis.
• High tea consumption is a potential source of excess fluoride exposure.
• A detailed dietary history is essential in evaluating osteosclerosis or elevated bone density.
Reference:
Izuora K, Twombly J, Whitford GM, Demertzis J, Pacifici R, Whyte MP. Skeletal fluorosis from brewed tea. J Clin Endocrinol Metab. 2011;96(8):2318–2324.
Agency for Toxic Substances and Disease Registry. Toxicological Profile for Fluorides, Hydrogen Fluoride, and Fluorine. US Department of Health and Human Services; 2022.
Wąsik A, Czerwinska M, Rachwal K, et al. Factors influencing fluoride content in tea infusions: a systematic review. Appl Sci (Basel). 2023;15(11):5974.

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