With the advent of Koch's immortal discovery of the bacillus tuberculosis it was thought by many that the problem of the early recognition of consumption had been solved. But the more careful physician soon realized that, while the presence of the tubercle bacilli in the sputum would confirm beyond a doubt his diagnosis of a tubercular disease of the respiratory tract, not finding them at one, two, or even more bacteriologic tests could not make him set aside conclusions arrived at by a careful physical examination.
If we consider the matter carefully we must admit that in very early cases of pulmonary tuberculosis the expulsion of bacilli with the expectoration, which is at that time exceedingly rare, can hardly be expected. There must be a disintegration of the tubercle before we can assume that the bronchial or pulmonary secretions should contain the specific organism of tuberculosis.
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