A pathological study of bamboo nodule of the vocal fold.

We examined pathologically a bamboo nodule of the vocal fold by means of immunohistochemical studies and scanning electron microscopic examination. A 38-year-old female showed a high index of antinuclear antibodies without any systemic symptoms but had complained of progressive voice disorder for 9 months. She had used her voice excessively in her occupation and for singing. Hematoxylin and eosin staining showed submucosal edema with lymphocyte and neutrocyte infiltrations and hyaline degeneration. Periodic acid methenamine silver staining showed hypertrophy of the basal lamina of the blood vessels. Immunohistochemical study showed IgG-positive cells in the blood vessel walls. Scanning electron microscopic study demonstrated immune complexes deposited as fine granules of high electrodense materials in the hypertrophic walls of the micro-blood vessels. After surgical resection of the bamboo nodules and advising her to avoid using her voice excessively, her voice improved gradually and the levels of IgG, immune complexes, and antinuclear antibody decreased for 1 year. These findings suggest that the bamboo nodules were not induced by an organ-specific reaction to an autoimmune disease, but mechanical damage to the micro-blood vessels induced by phonation injury of the vocal fold might have caused the deposit of high-molecular weight immune complexes in the damaged micro-blood vessels at the midportion of the vocal folds, which induced secondary inflammatory change at the midportion of the vocal fold.