- "Bone marrow histopathology revealed prominent diffuse sclerosis which in conjunction with urinary fluoride levels and computer cleaner inhalant abuse history supported the diagnosis of skeletal fluorosis. ...The serum fluoride level was within normal limits. Interestingly, urine fluoride was significantly elevated at 19 mg/L (ref. range: 0.2-3.2 mg/L) and the fluoride to creatinine ratio was significantly elevated (27.5 mg/g, upper limit of normal 3.0), rendering skeletal fluorosis the most likely diagnosis based on the patient’s history, presentation, imaging and laboratory findings".
Tucci JR, Whitford GM, McAlister WH, Novack DV, Mumm S, Keaveny TM, Whyte MP - "Skeletal Fluorosis Due To Inhalation Abuse of a Difluoroethane-Containing Computer Cleaner" J Bone Miner Res 32(1):188-195 (2017) doi: 10.1002/jbmr.2923. Epub 2016 Oct 14. PMID: 27449958; PMCID: PMC5977397
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5977397/
Abstract
Skeletal fluorosis (SF) is endemic in many countries and millions of people are affected worldwide, whereas in the United States SF is rare with occasional descriptions of unique cases. We report a 28-year-old American man who was healthy until 2 years earlier when he gradually experienced difficulty walking and an abnormal gait, left hip pain, loss of mobility in his right wrist and forearm, and progressive deformities including enlargement of the digits of both hands. Dual-energy X-ray absorptiometry (DXA) of his lumbar spine, femoral neck, total hip, and the one-third forearm revealed bone mineral density (BMD) Z-scores of +6.2, +4.8, +3.0, and -0.2, respectively. Serum, urine, and bone fluoride levels were all elevated and ultimately explained by chronic sniffing abuse of a computer cleaner containing 1,1-difluoroethane. Our findings reflect SF due to the unusual cause of inhalation abuse of difluoroethane. Because this practice seems widespread, particularly in the young, there may be many more such cases. © 2016 American Society for Bone and Mineral Research.
Ed. Note: Interesting how Tucci, Whitford et al. once again downplay SF, stating that "it is rare" - although no one is looking for it, nor is familiar with the various stages of SF.