Old tuberculin has considerable use in dermatology both as a diagnostic and as a therapeutic agent. It is a substance derived from a glycerin and beef broth culture of tubercle bacilli which have been killed with live steam, filtered and washed. In addition to the active skin-sensitizing principle, it contains variable amounts of glycerin, salts, peptones and metabolic bacterial products. The presence of foreign substances derived from the culture medium, while not impairing the value of tuberculin as a therapeutic agent, gives rise to such variation as to interfere considerably when it is used as a diagnostic agent. This applies particularly to the variable potencies of different batches of tuberculin produced by different firms over a period of years, making impossible exact comparable surveys in different parts of the country at different times.
The studies of Seibert and Lewis1 have shown that the phenomenon of sensitization to the tubercle
THOMAS CC. TUBERCULIN IN DERMATOLOGIC DIAGNOSIS: WITH SPECIAL REFERENCE TO THE PURIFIED PROTEIN DERIVATIVE (P.P.D.). Arch Derm Syphilol. 1942;45(3):544–549. doi:10.1001/archderm.1942.01500090091007
Dermatology in JAMA: Read the Latest
Customize your JAMA Network experience by selecting one or more topics from the list below.