Use of gas liquid chromatography in the clinical diagnosis of anaerobic pleuropulmonary infection.

Evidence of anaerobic infection was sought in 83 patients with pulmonary disease with anaerobic culture and gas liquid chromatography (GLC) of mucopurulent sputum, or pleural fluid where appropriate. Saliva samples from nine healthy controls and 14 patients with cystic fibrosis were examined by the same methods to assess anaerobic content. Clinically significant anaerobic pleuropulmonary infection was not found in our patients with bronchitis, bronchiectasis and cystic fibrosis and occurred in only some of our patients with empyema and lung abscess. GLC of pleural fluid (empyema) or sputum (lung abscess) was helpful in identifying these cases, when a strongly positive reading was obtained. The gas liquid chromatogram was negative or only weakly positive in those patients where the presence of anaerobes was clinically insignificant, most probably resulting from contamination of the sputum samples by saliva. Results were rapidly available and the need for transtracheal aspiration to obtain specimens of bronchial secretion uncontaminated by mouth flora was avoided. The semiquantitative GLC would therefore appear to be a useful method for investigating specimens from patients with suspected anaerobic pleuropulmonary infection.