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β-Lactamase-producing isolates ofBranhamella catarrhalis were first detected in France in 1977. The frequency of β-lactamase producers has increased, especially since 1980. An agar iodometric test, a fast chromogenic test and an acidimetric test were used to assess the β-lactamase-producing capabilities of 188 isolates ofB. catarrhalis obtained mainly from sputum and the pharynx. Data from the first 2 procedures indicated positive β-lactamase activity for all 49 strains ofB. catarrhalis identified, but there were some discrepancies in the acidimetric test results. Evidence from a diffusion technique showed significant increases in the inhibition diameters surrounding filter discs impregnated with amoxycillin in the presence of clavulanic acid, or with ampicillin in the presence of sulbactam, compared with discs of the penicillins used alone. Two types of enzyme activity emerged from examination of isoelectric focusing patterns. Type 1, having pI values of 5.35, 5.55 and 5.85, accounted for 87.2% of the enzyme-producing isolates. Type II, with pIs of 5.5, 5.9 and 6.25, occurred in 12.8% of isolates and appeared to be less widely distributed. The β-lactamase inhibitors clavulanic acid and sulbactam in combination with benzylpenicillin produced potentiated effects, as demonstrated by significant reductions in MIC (33- and 44-fold decreases, respectively). Higher concentrations of each inhibitor similarly affected the MICs of amoxycillin. A weak synergy occurred with cefoxitin, a β-lactamase-resistant β-lactam antibiotic, and the 2 β-lactamase inhibitors. BecauseB. catarrhalis has been shown to be a β-lactamase-producing pathogenic organism, the addition of enzyme inhibitors, such as clavulanic acid and sulbactam, to standard therapy may be beneficial.

A total of 176 strains identified asBranhamella catarrhalis were isolated from various clinical specimens, mainly sputum (71), pharynx (49), eye (24), nose (11), ear (6) and tracheal aspirate (7). B. catarrhalis appeared as Gram-negative cocci in white colonies which were oxidaseand catalase-positive and which did not produce acidification of sugars. The 3 related species, Neisseria caviae, N. ovis andN. cuniculi were also white but the‘true asaccharolyticNeisseria’ studied presented a yellow pigment. Only a few strains ofB. catarrhalis were able to grow on selective medium. However, when Catlin’s chemically defined medium was used, all strains ofB. catarrhalis had a unique requirement for arginine. This characteristic differentiatedB. catarrhalis fromN. caviae andN. ovis (non-requiring), N. cuniculi (required cystine, proline and arginine) andN. canis andN. elongata (both non-requiring). All strains ofB. catarrhalis reduced nitrate and nitrite, possessed deoxyribonuclease activity and hydrolysed tributyrin to butyric acid. B. catarrhalis liberated high concentrations of butyric acid, N. caviae, N. ovis andN. cuniculi moderate concentrations and other species of Neisseria itminimal concentrations. All strains ofB. catarrhalis were resistant to acetazolamide and the absence of γ-glutamyl transferase activity differentiatedB. catarrhalis from atypical meningococci which were always positive.

Using a simple and rapid microassay, we tested 100 strains of Neisseria gonorrhoeae isolated from 81 patients (41 men and 40 women) for their sensitivity to killing by normal human serum (NHS). The reproducibility of the test was good when the bactericidal end points were taken as the dilution of fresh NHS that killed more than 95% of the test organisms. The bactericidal end points of strains isolated either from different anatomical sites or from sexual partners correlated well with the levels of sensitivity to serum of corresponding isolates, as well as with auxotypes. When the strains were not highly resistant to killing by NHS, this marker gave a precise definition of each strain and permitted the differentiation of isolates belonging to common auxotypes. [ABSTRACT FROM PUBLISHER]

A total of 460 Neisseria gonorrhoeae isolates from patients seen at three clinics in Dakar, Sénégal, 1982-1986, have been investigated. In this period a significant change in antimicrobial susceptibility was observed: the percentage of strains susceptible to penicillin (MIC less than or equal to 0.08 micrograms/ml) fell from 61 to 18 (p less than 0.0001) and the percentage of resistant strains (MIC greater than or equal to 1.2 micrograms/ml) increased from 18 to 46. Among penicillin-resistant strains the proportion of penicillinase-producing strains (PPNG) was fairly constant (range 35-55%). The determination of susceptibility to anti-microbial agents performed locally allowed detection of approximately all PPNG strains whereas the increase in the occurrence of strains with chromosomally determined resistance was not revealed. The study comprised 70 PPNG strains of which 19% (13/70) carried the 7.4 kb Asian plasmid and 81% (57/70) the 5.3 kb African plasmid. None of these strains possessed the 38 kb conjugative plasmid, whereas it was found in 4.5% of the 376 non-PPNG strains available for plasmid analysis; 92% (410/446) of all strains had the small 4.2 kb plasmid and 5.4% (24/446) did not contain any plasmid. Overall, auxotype zero and proline-requiring strains were predominant, accounting for 53% (244/460) and 28% (131/460), respectively. In general, PPNG strains carrying the 5.3 kb plasmid were auxotype zero (49/57 = 86%) and those carrying the 7.4 kb plasmid were proline-requiring (9/13 = 69%). [ABSTRACT FROM PUBLISHER]

The auxotypes and serogroups of 250 consecutive isolates of Neisseria gonorrhoeae from Franceville, Gabon, including 33 penicillinase producing (PPNG) strains, were identified and the results tabulated for four periods. The PPNG and certain non-PPNG strains were isolated in clusters against a relatively stable pattern of non-PPNG biotypes. Most of the non-PPNG strains were non-requiring or proline requiring strains of serogroup WII or non-requiring strains that could not be grouped with commercially available antisera. No strain requiring arginine, hypoxanthine, and uracil was observed. The PPNG strains were all serogroup WI or ungroupable and non-requiring or proline or arginine dependent auxotypes. Only one non-PPNG strain required proline or arginine and was not serogroup WII. [ABSTRACT FROM PUBLISHER]