[Haemophilus isolates in children suffering from chronic upper respiratory tract infections].

For a three year period, between 1992 and 1994, 271 isolates of H. influenzae and H. parainfluenzae were examined using biochemical tests, beta-lactamase production and antibiotic susceptibility patterns. H. influenzae was examined by serological typing using polyvalent and monovalent sera a-f (Difco), as well. The strains were derived from children who were treated because of chronic pharyngitis. Sensitivity tests to Erythromycin, Gentamycin, Cefradine, Ampicillin, Doxycycline, Cefuroxime, Amoxicillin/Clavulanic Acid, Co-Trimoxazole, were performed with a standard disk-diffusion method. Biotyping was performed using API NH set (bioMerieux) and the ability to produce beta-lactamase was measured using iodometric method. Of 157 H. influenzae, 58 (36.9%) were typeable with H. influenzae antisera. The most common biotypes of these strains were I and II although biotypes III-VII were presented, as well. Of 114 H. parainfluenzae most of the strains showed the biotypes I and II. Its worth noting that 14% of H. influenzae and 15.8% of H. parainfluenzae strains were capable of beta-lactamase production. The strains of H. influenzae and H. parainfluenzae were most resistant to Cefradine and Co-Trimoxazole, respectively.