The Effect of Secondary Infections on Experimental Trachoma

The possibility suggested itself, in view of the theories already advanced with regard to the rô1e of secondary infections in the later manifestations of trachoma (1), that the implantation of common bacteria on the conjunctivae of monkeys already having well marked characteristic granulosis lesions might give rise to a condition showing less predominance of the follicular reaction and more of the hyperemic granulopapillary effect. We believe we have succeeded, by a suitable technique, in doing this and in producing thereby in the experimental animals a condition closely resembling the florid type of human trachoma (Type IIb and c of MacCallan). The organisms used were some of those which are found in the conjunctival sac of monkey and man with different types of granular conjunctivitis. Of themselves, they produced only a transient reaction or none, as Noguchi had already shown and as we ourselves had observed in control animals. When inoculated together with material containing Bacterium granulosis, they did not affect the usual action of this organism, but when introduced into a conjunctiva in which granulosis lesions were already well developed, they induced more of the characteristics of the florid stage of trachoma than have been hitherto observed in animals, notably increased hyperemia, edema and thickening, papillary hypertrophy, obscurity of blood vessels, and masking of the follicles. Microscopically these changes were accompanied by increased scar tissue formation, lymphoid infiltration, and papillary hyperplasia.