Diagnostic value of Calmette's tuberculin ophthalmo-reaction

Abstract

It is the aim of all Public. Health Authorities to prevent -the spread of Tuberculosis. One never picks up a medical paper without seeing some article on its prevention. This ophthalmo-reaction of Calmette's has proved itself wonderfully accurate, and if used systematically in schools, the medical man without much difficulty could separate out tubercular- children from the others.

There is no doubt that if tuberculosis is to be kept from spreading, tubercular children in a household or community must be kept -apart from those not affected.

Again it is all important to recognize tubercle early. The earlier the treatment is begun, the better result is are obtained often in surgery and medicine when there is .clinical evidence of tubercle, it is too late for satisfactory-treatment. What an easy thing for the practitioner to put a drop of Calmette's Test Solution into-the eye and if he gets a positive result, he knows to keep his eyes open. Especially is this valuable in Tubercular families.

Every now and then one reads of the dangers of the Test. I myself have not had a bad result. Some medical men own that there was a lesion of the eye before the test was done, which explains for itself the bad.results.

To make doubly sure of no bad results being got, first examine the eyes carefully. Then use a 1 in.200 Solution. If no reaction is produced by this very weak Solution, it is not conclusive that the person is not tubercular, but it is conclusive that by following the first instillation by a 1 in 150 or even 1 in 100 Solution the reaction is not likely to be so severe as to do any damage to the eye.

If on the other hand a positive reaction, however mild, is obtained with the 1 in 200 solution, it shows that the person is tubercular and that had a 1 in 150 or 1 in 100 solution been used, the reaction would have been very severe. I have heard of several doctors giving up the test as a result of having a mishap, but with care to the soundness of the eye and by using a 1 in 200 solution, I cannot see-how any bad result can follow.

Of course there are fallacies, but these have been pretty satisfactorily explained. The advanced tubercular lesions giving a negative reaction has been explained thus:

(1) During Chronic Tuberculosis an antitoxin is developed and thus an immunity is imparted to the tissues.

(2) Due to the fact that vitality is too low to give any inflammatory reaction.

Again negative results have been obtained in children where positive results Were expected, due to the carelessness of the doctor in not seeing that the drop goes into the eye or due to the child crying and the tears washing-the solution out of the eye. Such need not occur with due care on the part of the doctor.

In conclusion I unhesitatingly say that Calmette's Tuberculin Opthalmo-Reaction has a great future in the diagnosis of Tubercle in man.