The Culture of Tubercle Bacilli from Laryngeal Swabs: (Section of Comparative Medicine)

In a considerable proportion of cases of pulmonary tuberculosis there is no spontaneous expectoration, especially in female patients and patients under collapse treatment. A simple and efficient method is described to obtain suitable material for bacteriological examination in these cases. A laryngeal swab, made up from a piece of wire with cotton-wool wrapped round its end, is passed down the larynx and the patient asked to cough. Two swabs are taken from each patient. The swabs are passed through sterile test tubes containing 10% sulphuric acid and 2% sodium hydroxide solutions for five minutes in each and 2 Petragnani media inoculated with each swab. The cultures are examined after five days for contamination, and after twenty-eight days for macroscopical colonies of tubercle bacilli. The results obtained in two groups of cases of 166 and 107 patients were: 37.95% and 54.20% positive cultures respectively. The highest positive figures were obtained in female patients. Thus tubercle bacilli were demonstrated in a considerable proportion of cases previously regarded as sputum-negative or having no sputum. Apart from diagnosis the method gives valuable help in judging the efficiency of treatment. The finding of bacilli in early infiltrative lesions is of considerable practical as well as theoretical importance.