Mycobacteria in the Anterior Chamber of the Eye: Drug Therapy of Irido-Cyclitis through Vasoconstriction; Differentiation between BCG and Virulent Human M. Tuberculosis

In order to induce experimental iridocyclitis in rabbits, we injected M. tuberculosis into the anterior chamber of the eye. In this way we proposed to cause iridocyclitis with about the same picture as in man, and to establish whether the course of this iridocyclitis could be modified by vasoconstriction. It may be known that the rabbit is much less sensitive to human than to bovine tb 1. When we had injected human M. tuberculosis into the anterior chamber, there developed, contrary to our expectations, an extremely violent tb, which destroyed the eye, and which was sometimes followed by general dissemination. This showed that, although the rabbit is not very sensitive to human tb, this is quite different when the infection takes place through the anterior chamber 2. To induce iridocyclitis of the violence desired, we then used BCG, with which we obtained reproducible results. For the bacteriologist the above-mentioned experience was a reason to inject the anterior chamber INH-resistant M. tuberculosis, which are known to have lost something of their virulence. This produced iridocyclitis, the intensity of which lay between that caused by human M. tuberculosis and that caused by BCG. When 1 After infection with bovine tb the rabbit dies, whereas infection withhuman tb is overcome. This may be the basis of a method of differentiationbetween bovine and human M. tuberculosis. 2 In 1884, Robert Koch, in «Mitteilungen aus dem Kaiserlichen Gesundheits-amt” described “Impfung von Reinkulturen in die vordere Augenkammer”(inoculations of pure cultures into the anterior chamber of the eye) as themethod of choice to induce tb in rabbits in approximately one month. Hefound that the spread from the eye was very easy. Koch afterwards used theguinea-pig as a test animal. von Nordheim and Coster, Mycobacteria ... 443 acid-fast saprophytes are injected the picture becomes even more favourable. One of us has made use of these phenomena to assess in experiments his clinical impression that local vasoconstriction 3 may affect the course of inflammatory processes such as iridocyclitis.