The Synergism Between Mycotic and Tuberculous Infections of the Lungs

An attempt has been made to discuss the commensal relationship between fungus and tuberculous infections of the lungs. The coexistence of these two infections produces a more rapidly fatal issue in tuberculous individuals than one should expect from a consideration of the duration of the disease process in the lungs. Fungi from the expectorated sputum are usually saprophytic. It is safest to obtain the sputum specimens by intratracheal aspiration, and subject the fungus to animal inoculation, if there is any doubt regarding its pathogenicity.

Physicians should search diligently for coexisting pathogenic fungi in every tuberculous patient whose clinical course is unusually rapid or prone to relapse. The fact that 1.6 per cent (5 patients) of our clinically diagnosed tuberculous patients harbored pathogenic fungi in their tracheal excretions, although tubercle bacilli were never recovered from these 5 patients, should be remembered. The mycelial fungi are found more frequently than yeast-like fungi as the etiologic agents of pulmonary mycoses, associated with pulmonary tuberculosis. The close phylogenetical relationship of the mycobacterium tuberculosis to certain fungi, the actinomyces, and the frequently noted similar pathological changes in mycotic and tuberculous disease of the lungs are of interest. All ideas dealing with the cooperative relationship between the tubercle bacilli and fungi existing together in diseased tissues are highly speculative, as little, if anything, is known regarding such interacting or interplaying processes. Our investigations would suggest, in a limited number of cases, that the association of a fungus infection, of the lungs in a patient having pulmonary tuberculosis would augment and accelerate the activity of the tubercle bacilli, either directly, or by lowering the vitality and resistance of the patient to the end that a more unfavorable course of the tuberculous disease, marked by relapses and relatively rapid progression, may be observed. It is suggested that there is some factor present in this interplay of two coexisting infectious diseases, some prototaxic or symbiotic influences, which causes an added infection of the lungs with pathogenic fungi to increase the ravages of pulmonary tuberculosis.