Diffuse pulmonary meningotheliomatosis in a patient with autoimmune thyroiditis and chronic inflammatory disease

Diffuse pulmonary meningotheliomatosis (DPM) is an exceedingly rare benign condition characterized by innumerable minute pulmonary meningothelial-like nodules diffusely involving both lungs. We report a 44-year-old woman with Hashimoto's thyroiditis and chronic sinusitis requiring biologic therapy, who presented with incidentally discovered innumerable centrilobular ground-glass nodules. Extensive workup excluded infectious, malignant, and vasculitic etiologies. Surgical lung biopsy was consistent with DPM. This case is notable for younger age, absence of malignancy, preserved pulmonary function despite extensive radiographic disease, and a prominent systemic inflammatory phenotype.