Bacteriology of lower-respiratory-tract secretions, sputum, and upper-respiratory-tract secretions in "normals" and chronic bronchitics

Aspiration pneumonia, anaerobic infections, and lung abscess

Anaerobic pleuropulmonary infections are common in the setting of aspiration. Treatment is with penicillin or in mixed infections, penicillin and other appropriate antimicrobial agents. Four syndromes are commonly recognized. Simple pneumonitis resolves promptly with antibiotic therapy. If treatment is delayed, simple pneumonitis may evolve into a more fulminant process of necrotizing pneumonia with a significant mortality despite antibiotic therapy. Lung abscess, typically a subacute or chronic infection, responds well to antibiotic therapy so long as the cavity is drained via the communicating bronchus. Empyema requires surgical drainage by either closed or open thoracostomy if resolution is to be achieved.

Bacteriological findings in the transtracheal aspirate from patients with acute exacerbation of chronic bronchitis

Transtracheal aspirates from 87 patients with acute exacerbations of chronic bronchitis who had received no recent antibiotic treatment were examined. A single bacterial species was found in 83% of positive cultures. Predominant pathogens were Haemophilus influenzae and Streptococcus pneumoniae which occurred jointly or separately in 50% of positive cultures. Bacteria traditionally considered as non-pathogenic for the lower respiratory tract also appeared to play an aetiological role. Enterobacteriaceae and anaerobes were infrequent. No bacterial growth was found in 11 cases.

Anaerobic bacteriology of chronic bronchial disease. With a refined method of sampling bronchial secretions

A refined bronchoscopic method of sampling bronchial secretions is presented. The results show that this gives higher yields of aerobic pathogens than examination of expectorated sputum and the method also avoids pharyngeal contamination in suspected cases of anaerobic lung infection. Our results indicate that anaerobic organisms do not play a major role in causing sputum purulence in patients with chronic bronchitis, bronchogenic carcinoma or with less florid degrees of bronchiectasis. Anaerobic infections did not appear to occur as often as suggested by some reports from the United States.

Aspects of serum and sputum antibody in chronic airways obstruction

Immunoglobulin levels and precipitating antibody against a range of microbial antigens were measured in simultaneously collected serum and sputum samples from patients with chronic bronchitis (11), cystic fibrosis (9), bronchiectasis (9), and asthma (4). Sputum was prepared by dialysis and high-speed centrifugation methods. Results showed that it was possible to detect precipitating antibody in the sputum, and the rate was increased when both methods were used. A discrepancy was noted between the detection rate in the sputum and serum. This, combined with the lack of correlation between sputum and serum immunoglobulins, lack of relationship between bronchial inflammation and sputum immunoglobulins, and the lack of IgM in the sputum suggested that the antibody and immunoglobulin were locally produced. Sputum IgA (7S) in patients with chronic bronchitis was significantly lower (P less than 0-05) than that found in patients with cystic fibrosis and bronchiectasis. Significant differences (P less than 0-05) were also noted in serum IgG levels between patients with chronic bronchitis, bronchiectasis, and cystic fibrosis while serum IgM levels in patients with chronic bronchitis were significantly lower (P less than 0-05) when compared to serum levels in patients with cystic fibrosis. The presence of precipitating antibody in the sputum raises the possibility that type III reactions may be important in the pathogenesis of these conditions.

Agglutinin response to bacterial infection in acute exacerbations of chronic bronchitis

Agglutinin titres to Haemophilus influenzae, Streptococcus pneumoniae, Klebsiella pneumoniae, Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, and Proteus vulgaris in the serum of patients with acute exacerbations of chronic bronchitis, patients producing mucoid sputum, and healthy controls were determined. Serological evidence of infection with H. influenzae was found in 38 of 57 patients with acute exacerbations, and Str. pneumoniae infection in 10 of the 57 patients, but was generally absent from healthy control subjects and from patiens producing mucoid sputum. No serological evidence of infection with other organisms named above was found to be associated with exacerbations of chronic bronchitis. Ten patients with acute exacerbations were without serological evidence of infection by any of the bacteria tested.

Bacterial flora and infection in patients with brain injury

✓ Twenty-five patients with acute head trauma were studied prospectively for appearance of infection during hospitalization in an acute care unit. The study demonstrates: multiple changes in bacterial flora particularly in the respiratory tract, a significant morbidity due to bacterial changes in the respiratory tree, a negligible incidence of bacterial disease due to physiological monitoring procedures, and an inability to correlate changing flora with specific therapeutic or manipulative procedures except tracheostomy. Mortality correlates well with the severity of illness and indirectly with changes in bacterial flora. Despite the frequent isolation of coagulase-positive staphylococci, severity of infectious complications correlate most closely with the acquisition of gram-negative organisms in the respiratory tract.

Ampicillin and tetracycline in the treatment and prophylaxis of chronic bronchitis

Ampicillin and tetracycline, in doses of 2 g a day, were compared in the treatment of acute exacerbations of chronic bronchitis. Seventy-nine patients were followed for 3 to 29 months and were treated for 118 exacerbations. Clinical improvement occurred after 10 days of treatment with either drug in over 80% of the cases. Haemophilus influenzae and Diplococcus pneumoniae were eradicated from the sputum more than 60% of the time, but in general there was a poor correlation between bacteriological clearing and clinical response. The effect of chemoprophylaxis with ampicillin and tetracycline in doses of 1 g a day on the frequency of acute exacerbations of bronchitis was compared with that of a placebo. Seven hundred eighty prophylactic regimens, consisting of one capsule every 12 hr for 5 days beginning with the first sign of a cold, were prescribed for 76 patients. Irrespective of the regimen, an acute exacerbation of bronchitis was encountered at approximately 13% of the follow-up visits to the clinic.

A search for mycoplasma infections in patients with chronic bronchitis

Throat and bronchoscopy specimens for mycoplasma isolation studies were collected from 22 patients with chronic bronchitis and 20 patients without chronic bronchitis. Twenty-six of 50 patients attending a chronic bronchitis clinic had throat, nasal, or sputum specimens collected for attempted mycoplasma isolation, and all of these patients had multiple serum samples taken for mycoplasma antibody studies. Mycoplasmas were recovered from throat and bronchoscopy specimens of the chronic bronchitic and non-bronchitic patients with about equal frequency. The concentration of organisms in the bronchoscopy specimens of two patients with chronic bronchitis was greater than in their throat specimens, suggesting downward spread and multiplication of mycoplasmas rather than contamination by passage of the bronchoscope. Eighty-three per cent of the rises in mycoplasma antibody titre in chronic bronchitic patients occurred during or immediately after an acute respiratory illness, and this relationship of rise in antibody titre to acute illness was significantly more frequent than rises in antibody titre not associated with illness. We suggest that mycoplasmas may be present in the bronchi of some patients suffering from chronic bronchitis and that, while such mycoplasma infections are often silent, they may become sufficiently active during infection by other agents to stimulate a mycoplasma antibody response.

Mechanisms of antibacterial action in the respiratory system

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AEROBIC AND ANAEROBIC BACTERIAL COUNTS OF NASAL WASHINGS: PRESENCE OF ORGANISMS RESEMBLING CORYNEBACTERIUM ACNES

Watson, Elinor D. (Washington University, St. Louis, Mo.), Nanci J. Hoffman, Richard W. Simmers, and Theodor Rosebury . Aerobic and anaerobic bacterial counts of nasal washings: Presence of organisms resembling Corynebacterium acnes . J. Bacteriol. 83: 144–148. 1962.—Aerobic and anaerobic colony counts in blood agar were made of 40 samples of nasal washings from five healthy adults. The anaerobic counts were consistently and significantly higher, in line with findings previously reported by others for skin, saliva, and feces. Catalase-forming diphtheroids utilizing lactate anaerobically, tentatively identified as members of the Corynebacterium acnes group, were conspicuous in the anaerobic cultures.