Abstract
A 34-year-old woman visited the hospital suffering from enanthema of the tongue, hair loss, and nonproductive cough. Corticosteroid administration slightly resolved the enanthema and hair loss, but not the nonproductive cough. She was transferred to another hospital for the resection of a retroperitoneal mass, which was histopathologically diagnosed as unicentric, hyaline vascular type Castleman's disease. She was then referred to our hospital due to progressive dyspnea and was diagnosed as having bronchiolitis obliterans based on computed tomography scan findings and a lung function test, while paraneoplastic pemphigus was clinically considered for her enanthema. After her death from respiratory failure in spite of corticosteroid administration, autopsy confirmed constrictive bronchiolitis in the lung. Mucocutaneous lesions, clinically considered as paraneoplastic pemphigus, were histologically different from pemphigus. The constrictive bronchiolitis and other pathological findings, including nonviral chronic hepatitis and interstitial nephritis, confirmed the diagnosis of paraneoplastic autoimmune multiorgan syndrome associated with the Castleman's disease.