Case Report: Is it COPD? It is Fabry disease: a case in which bronchodilators were briefly used but not continued, prioritizing enzyme replacement therapy.

BACKGROUND: Fabry disease, an X-linked lysosomal storage disorder, can present with mixed ventilatory dysfunction on pulmonary function testing. In patients with a smoking history, this finding may trigger a reflexive consideration of COPD and unnecessary bronchodilator use. We report a case where bronchodilators were briefly used following the diagnosis of Fabry disease, highlighting the clinical inertia that persists even after a definitive diagnosis.

CASE PRESENTATION: A 39-year-old male with a 20-pack-year smoking history was diagnosed with Fabry disease through family cascade screening (α-galactosidase A activity: 4.93 nmol/L; plasma lyso-Gb3: 328.92 nmol/L; hemizygous GLA variant). Multisystem evaluation revealed mixed ventilatory dysfunction (FEV1/FVC 54.59%) without respiratory symptoms, left ventricular hypertrophy (septum 14-17 mm, posterior wall 15 mm), proteinuria (1.01 g/24 h), and corneal verticillata. Chest CT showed no emphysema. During hospitalization, inhaled budesonide plus ipratropium bromide (a bronchodilator) was briefly administered. However, recognizing that the ventilatory dysfunction was a manifestation of Fabry disease itself rather than COPD, the patient was discharged without a bronchodilator prescription. Enzyme replacement therapy (ERT) with agalsidase alfa (0.2 mg/kg every 2 weeks) was initiated as long-term disease-modifying treatment.

CONCLUSION: Even after Fabry disease is confirmed, the presence of a smoking history and abnormal spirometry can trigger reflexive bronchodilator use, illustrating powerful clinical inertia. Respiratory physicians should strictly adhere to COPD diagnostic criteria. Once Fabry disease is diagnosed, ERT should be prioritized as the disease-modifying therapy, and bronchodilators, if used at all, should be reserved for symptomatic patients as an adjunct, not a substitute.