Studies on Bacterium Granulosis in Relation to Trachoma. (III-IV). ∗

Abstract

By repeated instillation of freshly isolated cultures of Bacterium granulosis, or by a single subconjunctival injection of this organism, granular conjunctivitis was produced in several rhesus monkeys. This confirms the work of Noguchi. 1 Olitsky, Knutti and Tyler, 2 and Thygeson. 3 It was observed, moreover, that by repeated irritation with powdered, dry, sterilized Portland cement (applied by means of a cotton swab), or by previous inoculation with a virulent hemoglobinophilic bacillus (H. influenzae), the monkeys' conjunctivae were at times rendered more vulnerable to infection with B. granulosis. Best results were, however, obtained by the subconjunctival injection of freshly excised, macerated, infected monkey tissue (tarsus and conjunctival follicles) containing B. granulosis.

Clinically and histologically, the conjunctival lesions thus induced were similar to those produced by transfer of human tissue; that is, bits of conjunctiva, follicles, or secretions which had been freshly removed from patients with active trachoma, including pannus. Lesions produced by the latter method (which consisted of either subconjunctival injection or rubbing the material thoroughly into the conjunctiva with the aid of a cotton swab), were also transmissible in series from one rhesus monkey to another and developed more readily on a conjunctiva which had been repeatedly irritated by means of Portland cement powder.

In several monkeys which showed no gross evidence of follicles after inoculation with Noguchi's bacillus, or with tissue removed from monkeys which had developed lesions in response to infection with material taken directly from human trachomatous cases, it was demonstrated that microscopical evidence† of changes indicative of a chronic inflammation, or non-apparent infection, 4 were present. These changes consisted of lymphocytic and plasmo-cellular infiltration, edema of the conjunctiva with mucoid degeneration of the cylindrical cell epithelium, and congestion of the capillaries.

By employing the usual subconjunctival method of injection in rhesus monkeys, no evidence of a filtrable virus was found in tissues removed from monkeys whose conjunctivae had developed lesions in response to inoculation with human trachomatous material, or with virulent cultures of B. granulosis.