De Grandmont[53] records the case of a young man recovering from typhoid, complicated with jaundice and nephritis, who was attacked by iritis with posterior synechiæ and hypopyon. Paracentesis was done, and the pus of the anterior chamber was transferred to agar-agar. Two days later a pure culture was obtained presenting all the reactions and characteristics of the bacillus of Eberth. Of this culture a small quantity was injected into the vitreous of a rabbit. A month later the rabbit was killed, when the liver and intestines were found to be infiltrated with the same bacillus of Eberth.
In erysipelas de Grandmont has seen a hyalitis from which a culture was grown on gelatine that presented all the morphological characteristics of erysipelas.
He has also met with a case of hyalitis associated with puerperal septicæmia, and he has no doubt that it was the result of a similar microbic invasion of the vitreous.
Gout does not render patients immune from tuberculous, syphilitic or gonococcal disease, and when in such so-called diathetic stocks an iritis occurs, especially in gonorrhœa, years after the primary disease, it is probable that gout, rather than lues, will be assigned as the cause.
The local appearances of iritis are identical in gonococcal and other infective iritides; they resemble clinically those seen in syphilis and tubercle except that in these there are sometimes condylomata of the iris in the one and tuberculous nodules in the other. To be comparable a gouty iritis should be characterised by iritic tophi.
“Arthritic” Iritis.—Forty-eight is a large percentage in Hutchinson’s cases of ocular disease associated with gout and rheumatism, and it is justifiable to assume that there was something more than coincidence in the triple entente of diathesis, arthritis and iritis. But the fact that the poisons of syphilis and gonorrhœa, etc., are potent causes of iritis is indisputable, and therefore the patients might have suffered from it even if they had never had either gout or “rheumatism.” Consequently these articular diseases are both superabundant and superfluous, and they may have no etiological status. A patient afflicted with arthritis is very susceptible to an associated attack of iritis provided that there is a septic focus anywhere in the body.
A practical point to remember, especially in gonorrhœa, is that the onset of joint trouble should warn us to anticipate the possibility of an associated iritis and should prompt us to instil atropine at an early stage. We should forestall the disease by treating the suspicion. The frequency with which gonorrhœa is followed sooner or later by iritis entitles this ocular phenomenon to be considered a secondary symptom of gonorrhœa, as it is of syphilis.
Before the potency of distant infective foci (for example, in nasal disorders, pyorrhœa, sinusitis, etc.) to produce ocular disease was recognised, there was justification for the inclusion of a so-called idiopathic iritis, but it is seldom now that we have to be satisfied with this negative diagnosis. Nevertheless the assignment of a toxæmic etiology must be based on a definitely ascertained focus of toxic absorption, or failing this, at least on symptoms of general malaise which render such a focus highly probable.
Frequency a Factor in Diagnosis.—It was known a century before the birth of bacteriology that gonorrhœa caused iritis. It was also noted that certain constitutional symptoms occurred in syphilis, and that among them not infrequently iritis was one. Observation and deduction was the process with our forefathers, and it seldom led them astray.
If in any sequence of events cause and effect are to be established when there is no obvious proof of connection, we may have to be content with an empirical diagnosis, and this was the position before the discoveries of bacteriology enabled us to place the etiology of iritis on a firm basis. How then did our ancestors know that syphilis and gonorrhœa caused iritis? Was it not—