This article is only available in the PDF format. Download the PDF to view the article, as well as its associated figures and tables.
To the Editor:
—In The Journal, May 30, Dr. J. D. Pilcher reported his experience with the keeping quality of tuberculin dilutions. So much has been written since the introduction of tuberculin about its potency that one is at a loss to know when tuberculin dilutions can be used satisfactorily and with dependability. I have used tuberculin for more than twenty years, both for therapy and for diagnostic purposes. Dr. Pilcher is correct when he states that tuberculin is still of good potency after dilution for months or even years.With the dilution 1: 100 I find that the last drop, even after months and years, is always of full potency. Using only Koch's original old tuberculin, prepared in Germany, I made a late dilution from a package said to have been prepared May 10, 1929, the expiration date of which is given as July 4, 1934. The enclosed circular
Ritter J. TUBERCULIN DILUTIONS. JAMA. 1931;97(7):480. doi:10.1001/jama.1931.02730070046028
Coronavirus Resource Center
Customize your JAMA Network experience by selecting one or more topics from the list below.
Create a personal account or sign in to: