Cat-scratch disease skin test. Studies of specificity and histopathologic features.

Microscopical examination of biopsy specimens from cat-scratch skin test sites, performed in patients with cat-scratch disease (CSD), sarcoidosis, tuberculosis, and other granulomatous diseases, showed noncaseating granulomatous dermal inflammation in 11 of 12 patients with CSD and in some patients with sarcoidosis or tuberculosis. Biopsy of cat-scratch skin test sites may be a useful ancillary procedure in diagnosing CSD if other granulomatous diseases are excluded.