RADIOGRAPHIC APPEARANCE OF CHLAMYDIA-PNEUMONIAE (TWAR STRAIN) RESPIRATORY-INFECTIONS

PURPOSE: To report the spectrum of radiographic findings associated wi th a new respiratory pathogen: Chlamydia pneumoniae (TWAR strain). MAT ERIALS AND METHODS: Radiographs of 55 adult patients hospitalized with serologic evidence of C pneumoniae were retrospectively reviewed. RES ULTS: On the basis of serologic criteria, two types of acute respirato ry infection are possible: primary (first exposure) infections and rec urrent, acute infection in a previously exposed individual. In the pri mary group, alveolar opacities (65%) with a unilateral distribution (7 1%) were most common at admission. Cavitary disease and hilar or media stinal lymphadenopathy were uncommon. Small to medium-sized pleural ef fusions were common in both primary and recurrent groups during hospit alization. Also, both groups tended to progress to bilateral, mixed, i nterstitial and alveolar changes during the course of infection. CONCL USION: Different radiographic patterns exist for the two types of acut e C pneumoniae infection.