RESUMEN
BACKGROUND: Combined pulmonary fibrosis and emphysema (CPFE) is a rare entity of unknown etiology. It usually occurs in the context of smoking and, less commonly, connective tissue disease. However, it has been rarely previously described in the context of vasculitis. OBSERVATION: We report a case of CPFE occurring in a 44-year-old man, who was a light smoker without any previous medical history. He presented with fever, chronic cough and breathlessness that progressively evolved to acute respiratory failure. At the initial evaluation, CT scan showed emphysema and patchy bilateral areas of ground-glass opacity. Three years later, the patient simultaneously developed a honeycomb fibrosis and a microscopic polyangiitis with renal involvement justifying the introduction of an immunosuppressive treatment in combination with high dose of systemic corticosteroids. After a stabilization period of 6years, the patient gradually developed chronic respiratory failure with moderate pulmonary hypertension requiring long-term oxygen therapy and nocturnal non-invasive ventilation. CONCLUSION: The association of microscopic polyangiitis to CFPE suggests that autoimmune diseases may have a common pathogenic role in the development of emphysematous and fibrotic lesions in CPFE.