Necrotizing arteritis occurring in an intralobar pulmonary sequestration of a patient without systemic vasculitis...

Necrotizing arteritis is a complex lesion of pulmonary hypertension, as are plexiform lesions, and is classically recognized as grade 6 in the Heath and Edwards grading scheme for hypertensive pulmonary vascular disease. The vascular changes observed in intralobar pulmonary sequestration have been reported to be similar to those observed in pulmonary hypertension, such as plexiform lesions. However, necrotizing arteritis occurring in an intralobar sequestration of a patient without systemic vasculitis syndrome has never been reported to our knowledge. Here, we report a case of a 38-year-old woman with pulmonary sequestration detected on a medical checkup. She was treated with surgery, and subsequent pathological analyses revealed necrotizing vasculitis in her sequestrated lung. We suspected systemic vasculitis syndromes, such as Takayasu arteritis, polyarteritis nodosa, and antineutrophil cytoplasmic antibody-associated vasculitis. However, physical and blood examination did not show any other abnormalities, and hence, she did not have systemic vasculitis syndrome. Immunohistochemical analyses of the resected specimen showed that inflammatory cells of the arteries were mainly composed of T lymphocytes. T-lymphocytic inflammation with little neutrophil and histiocyte infiltration may be a pathological feature of necrotizing arteritis observed in pulmonary sequestration. This is the first case to our knowledge of necrotizing arteritis in an intralobar pulmonary sequestration of a patient without systemic vasculitis syndrome.