[Immunofluorescence technique applied at serological diagnosis of the respiratory tract infections from gram-negatives bacteria (author's transl)].

The immunofluorescence indirect technique was evaluated for detecting specificities, Ig classes, and levels of serum and sputum antibodies against bacteria isolated from sputa in patients with broncho-pulmonary infections. Results obtained with the FA method were compared with those obtained with a passive haemagglutination test. The former method gave much more reliable results than the latter. By using FA indirect method it was possible to assess pathogenicity of baceterial strains isolated from sputum and to establish their ethiological significance in many clinical cases whose sputum cultures were impossible or difficult to evaluate, as for instance in a patient with a chronic bronchitis exacerabtion caused by a strain of Aeromonas hydrophila. Further investigation are suggested in order to improve technically the FA method and to find the easiest and most reliable way out to evaluated the effectual relationship between bacteria in sputum and immunoglobulin response in sputum or in serum of patient with respiratory tract infections due to bacteria.