The Tubercle Bacillus
Koch succeeded in staining the tubercle bacilli after long soaking of cover-slip preparations in alkaline methylene-blue and then using vesuvin as a brown contrast stain. Ehrlich first stained for fifteen to twenty minutes with an aqueous solution of aniline methyl violet or fuchsin, and then decolorised with dilute nitric acid, which eliminated the colour from everything except the tubercle bacilli. Other methods have been since devised, of which the following is the most convenient, especially for the examination of suspected sputum. For more complete study of the biological relations of the tubercle bacillus it is necessary to cultivate it on or in artificial media in the laboratory. The resistance to desiccation shown by the tubercle bacillus is its most significant biological feature. The best temperature for the growth of the mammalian tubercle bacillus is 37-38ºC. Cadeac and Malet have produced positive results by inoculation of material from tuberculous lungs which had previously been buried for 167 days.
Sources Of Infection (
This chapter shows that inhaled dust can penetrate to the air cells of the lungs. It provides the evidence for this statement, and the discussion of the relative share of this and other methods of infection. The chapter discusses the operation of infection by dust and by spray, as far as possible in the historical order of the most important experiments that have been made. Dried sputum is much more likely to cause infection, as, owing to the negligence with which the expectoration of phthisical patients is treated, it must evidently enter the atmosphere in considerable quantity. Heymann made experiments to determine the local dispersion and limitation of the sputum drops. Experiments were also made by Heymann on the duration of suspension in air of droplets containing tubercle bacilli. Tubercle bacilli have been frequently found in the dust of railway carriages, omni-buses, and tram-cars.
The Early Recognition of Phthisis in Relation to its Prevention
For both its successful treatment and the complete prevention of spread of infection, phthisis must be recognised at an early stage. The Public Health Department of Brighton is the focus of all the measures, prophylactic, curative, and sanitary, which are taken in the treatment and the prevention of this disease. In persons of tuberculous family history periodical weighing is one of the best means of ensuring the early recognition and treatment of disease. Of means for the early detection of tuberculosis, other than physical examinations and the testing of the sputum, the use of tuberculin is the best known. A local method of using tuberculin as a means of diagnosis has been described recently by Calmette, which may prove to be valuable. The Roentgen ray photograph of a chest in which there is an early tuberculous focus sometimes shows a shadow at the affected part.
Oscillatory Positive Expiratory Pressure in Chronic Obstructive Pulmonary Disease
Published in COPD: Journal of Chronic Obstructive Pulmonary Disease, 2016
Evidence-based guidance for the use of airway clearance techniques (ACT) in chronic obstructive pulmonary disease (COPD) is lacking in-part because well-established measurements of pulmonary function such as the forced expiratory volume in 1s (FEV1) are relatively insensitive to ACT. The objective of this crossover study was to evaluate daily use of an oscillatory positive expiratory pressure (oPEP) device for 21–28 days in COPD patients who were self-identified as sputum-producers or non-sputum-producers. COPD volunteers provided written informed consent to daily oPEP use in a randomized crossover fashion. Participants completed baseline, crossover and study-end pulmonary function tests, St. George's Respiratory Questionnaire (SGRQ), Patient Evaluation Questionnaire (PEQ), Six-Minute Walk Test and 3He magnetic resonance imaging (MRI) for the measurement of ventilation abnormalities using the ventilation defect percent (VDP). Fourteen COPD patients, self-identified as sputum-producers and 13 COPD-non-sputum-producers completed the study. Post-oPEP, the PEQ-ease-bringing-up-sputum was improved for sputum-producers (p = 0.005) and non-sputum-producers (p = 0.04), the magnitude of which was greater for sputum-producers (p = 0.03). There were significant post-oPEP improvements for sputum-producers only for FVC (p = 0.01), 6MWD (p = 0.04), SGRQ total score (p = 0.01) as well as PEQ-patient-global-assessment (p = 0.02). Clinically relevant post-oPEP improvements for PEQ-ease-bringing-up-sputum/PEQ-patient-global-assessment/SGRQ/VDP were observed in 8/7/9/6 of 14 sputum-producers and 2/0/3/3 of 13 non-sputum-producers. The post-oPEP change in 3He MRI VDP was related to the change in PEQ-ease-bringing-up-sputum (r = 0.65, p = 0.0004) and FEV1 (r = –0.50, p = 0.009). In COPD patients with chronic sputum production, PEQ and SGRQ scores, FVC and 6MWD improved post-oPEP. FEV1 and PEQ-ease-bringing-up-sputum improvements were related to improved ventilation providing mechanistic evidence to support oPEP use in COPD. Clinical Trials # NCT02282189 and NCT02282202.
Association between Eosinophilic Airway Inflammation and Persistent Airflow Limitation
Published in Journal of Asthma, 2013
Objective. We aimed to evaluate the association between eosinophilic inflammation in induced sputum and pulmonary function and persistent airflow limitation in children. Methods. A total of 92 asthmatic children and 72 controls were enrolled in this study. Eosinophil count (%) and eosinophil cationic protein (ECP) levels were measured in induced sputum. We performed spirometry and a methacholine challenge test, and measured total eosinophil count, total serum IgE, and serum ECP in all subjects. Results. Asthmatic children had significantly higher levels of sputum eosinophils (9% vs. 0%; P < 0.001) and sputum ECP (2.3 ± 0.7 vs. 1.6 ± 0.6 log µg/L, p < .001) than controls. Sputum ECP levels showed a significant negative correlation with post-bronchodilator (post-BD) FEV1 (r = –0.307; p = .001) and post-BD FEV1/FVC (r = –0.286; p = .002), whereas sputum eosinophils showed no correlation with post-BD FEV1 and post-BD FEV1/FVC. However, no significant differences in sputum ECP and sputum eosinophil counts were observed in asthmatic children with and without persistent airflow limitation. Conclusions. Our findings suggest that sputum eosinophilic inflammation, especially ECP, is associated with pulmonary function and persistent airflow limitation, which is manifested by low post-BD FEV1/FVC.
Minocycline, Doxycycline and Tetracycline Levels in Serum and Bronchial Secretions of Patients with Chronic Bronchitis
Published in Pathology, 1975
Serum and sputum levels of minocycline, doxycycline and tetracycline were determined in patients with chronic bronchitis who were producing copious amounts of purulent sputum. Antibiotic estimations were carried out by the plate agar diffusion method using the Oxford staphylococcus. A close correlation was obtained between the sputum and the average serum levels for patients receiving tetracycline. Values obtained for minocycline showed a poor correlation between serum and sputum. A correlation between serum and sputum levels of doxycycline could not be established due to the low levels present in sputum. Our results indicate that while adequate serum levels of tetracycline reflect the attainment of therapeutic concentrations in bronchial secretions; the same predictions cannot be made for minocycline or doxycycline.