Inhalation of Air Dust Cleaner Causing Skeletal Fluorosis

Presentation Number: SUN 322
Date of Presentation: April 2nd, 2017

Perihan Dimachkie*1, Katherine Peicher2 and Naim M Maalouf2
1University Of Texas Southwestern Medical Center, Dallas, TX, 2University of Texas Southwestern Medical Center, Dallas, TX

Abstract

Background:

Skeletal fluorosis is an osteosclerotic metabolic bone disorder caused by excessive ingestion or inhalation of fluoride. It afflicts millions of individuals worldwide due to endemic exposure, but it is very rare in the United States. We report a case of skeletal fluorosis due to inhalational abuse of a fluoride-containing air dust cleaner.

Case presentation:

A 33-year-old man with no past medical history presented to his primary care physician with complaints of progressively worsening low back pain for the past two years. His pain was worsened by movement and improved by rest. Physical examination was notable for loss of lumbar lordosis, and significant tenderness on palpation of his lumbar spine. Initial spine X-rays were notable for uniform osteosclerosis and loss of the normal lumbar curvature. The patient was subsequently referred to the endocrinology clinic for further workup. A skeletal survey showed uniform generalized osteosclerosis in the long bones, entire spine, rib cage, and pelvic bones. DXA scan showed Z-scores of +10.7 at the lumbar spine, +6.4 at the femoral neck, +6.5 at the total hip, and +1.0 at the 1/3 radius. Laboratory studies were notable for elevated serum alkaline phosphatase (334 U/L, ref: 40-129 U/L) compared to a normal value three years prior (64 U/L), and primarily of bone origin, suggesting acquired osteosclerosis. Urine N-telopeptide was also elevated (153 nM BCE/mM Cr, ref: 9 – 60). Additional studies were notable for normal serum 25-OH-Vitamin D (32 ng/mL), calcium (9.6 mg/dL), albumin (4.2 g/dL), phosphorus (3.4 mg/dL) and creatinine (0.94 mg/dL), a non-reactive hepatitis C antibody, and normal serum ceruloplasmin and tryptase. Serum and urine protein electrophoresis showed no monoclonal component. Serum fluoride concentration returned elevated (2.8 mg/L, ref: 0.0 – 0.2 mg/L). Initially, the source of the fluoride excess could not be identified as the patient denied any “typical” risk factors such toothpaste ingestion, or drinking well water or excess tea. At his follow-up visit, the patient was found inhaling from a can of an air duster keyboard cleaner hidden in an inner pocket. Upon questioning, he admitted huffing 2-7 cans weekly of a fluorocarbon-containing air dust cleaner for the past three years to achieve a euphoric feeling, explaining the source of his fluorosis.

Conclusion:

Fluoride inhalation can be a potential source for skeletal fluorosis, and should be suspected in patients with acquired osteosclerosis as “huffing” is reported to be increasingly practiced in the U.S.

 

Nothing to Disclose: PD, KP, NMM