9336 Bone Pain Caused By Computer Cleaners Huffing

Abstract

Abstract Disclosure: M. Sokrab: None. V.S. Rao: None. P. Shah: None. J.L. Shaker: None. A 47 year-old woman was evaluated 2/2024 for bone pain especially in the forearms and lower legs. The symptoms were worse since about 4/2023. Initial evaluation 11/2023 revealed elevated alkaline phosphatase levels and markers of bone remodeling (P1NP 396 ug/dl, normal; 20-101 and C-telopeptide 4389, normal; 177-1015. The plasma fluoride level was 17.1 mcmol/L (normal; < 4.1). There was no history of excess exposure to fluoride from dental products. She did not drink powdered iced tea or use green tea capsules. There was no industrial fluoride exposure and she consumed city water. She used inhaled fluticasone twice weekly but was not taking other fluoride containing medications, particularly voriconazole. She reported huffing computer cleaner containing difluoroethane between mid 2023 and early 2024. On examination, she had diffuse skeletal tenderness especially over her forearms and lower legs. Lab data revealed calcium 9.2 mg/dl (normal, 8.6-10.2), albumin 4 g/dl, phosphorus 3.6 mg/dl (normal, 2.5-4.5), creatinine 1.08 mg/dl (normal, 0.5-1.1), ionized calcium 1.33 mmol/l (normal, 1.18-1.33), pH normalized ionized calcium 1.25 mmol/l (normal, 1.18-1.33), PTH 126 pg/ml (normal, 15-72), 25(OH)vitamin D 29.5 ng/ml (normal, 20-50), and alkaline phosphatase 287 u/l (normal, 40-120) with a predominant elevation of the bone isoenzyme. The bone specific alkaline phosphatase was 93.4 mcg/l (normal, 7.0-22.4). The SPEP revealed a biclonal IgG Kappa monoclonal protein too small to quantify. The repeat fluoride level was 1.2 mg/l (normal, <0.05). Imaging included diffuse uptake on bone scan as well as periostitis/periosteal thickening involving legs, arms, and hands. There was axial osteosclerosis. Our patient appears to have skeletal fluorosis. Although the time-line of reported huffing and symptoms is not completely consistent, we could find no other exposure to fluoride and speculate she may have been huffing before she recalls. Skeletal fluorosis (SF) is endemic in some countries generally related to drinking water or tea that is high in fluoride, In the US, SF is caused by abnormal use of fluoride-containing dental products, excessive consumption of powdered iced tea containing fluoride, chronic use of the antifungal agent voriconazole and now more often huffing abuse of computer cleaners containing difluoroethane. The number of reported cases of huffing-related SF appears to be increasing and greater awareness of this problem is needed. Presentation: 6/1/2024