Asthma associated with denatonium benzoate in a healthcare worker in Taiwan: A case report

RATIONALE: Denatonium benzoate is a useful indicator to ensure that the respirator being used by an individual forms a tight enough seal to adequately protect against unwanted airborne exposure. Although the relative risk for adverse effects of fit testing using denatonium benzoate is low, the absolute number of workers with adverse reactions may nevertheless be sizeable. PATIENT CONCERNS: A 34-year-old female nurse rapidly developed shortness of breath, cough, and agitation after denatonium benzoate fit testing. She had a history of allergy to shrimp, crab, mite, and disinfecting products (containing quaternary ammonium). DIAGNOSES: Due to typical symptoms of asthma after exposure to denatonium benzoate aerosol without any other apparent cause, serial pulmonary function tests indicating obstructive lung function and a higher concentration of immunoglobulin antibody E, she was diagnosed with allergic asthma. INTERVENTIONS: This patient was treated with omalizumab (Xolair), corticosteroid, β(2) agonist, montelukast, and Symbicort turbuhaler. OUTCOMES: The patient showed quick responses after treatment with diphenhydramine (intramuscularly), fenoterol HBr (inhalation), and prednisolone (oral). Approximately 2 weeks later, she suffered from difficulty breathing and asthmatic symptoms again when she was exposed to polished wax and disinfectant. She was treated with omalizumab (Xolair), corticosteroid, β(2) agonist, montelukast, and Symbicort turbuhaler. The patient was in stable condition with improvement in symptoms during follow-up. LESSONS: There may be potentially important health risks when healthcare workers are exposed to denatonium benzoate. Individuals who have a history of allergy to disinfecting products (containing quaternary ammonium) should avoid exposure of denatonium benzoate. More advanced research is needed in the future.