[Epidemiology of Haemophilus influenzae strains collected in 2004 in France and in vitro assessment of their susceptibility to antibiotics]. / Epidémiologie et évaluation de la sensibilité aux antibiotiques de souches d'Haemophilus influenzae isolées en 2004 en France.

OBJECTIVES: The aim of this study was to describe the epidemiology of H. influenzae strains collected in 2004 at the National Reference Center and to evaluate their susceptibility to various antibiotics. METHODS: Demographic and clinical characteristics, capsular serotyping by slide agglutination with specific antisera, beta-lactamase by a chromogenic cephalosporin test (Nitrocefin) and MICs of amoxicillin, co-amoxiclav, cefpodoxime, cefaclor, cefuroxime, cefotaxime, erythromycin, pristinamycin and telithromycin by agar dilution method on Haemophilus Test Medium were determined for each strain. RESULTS: 807 strains of H. influenzae were identified: 41.8% from bronchial secretions (BS), 16.2% from conjunctivitis, 6.6% from otitis media (OM), 4.2% from CSF and 8.6% from blood cultures. 95.6% of strains was not capsulated and 4.4% was of serotype b, e, or f. 26.3% of strains was beta-lactamase producing (TEM type). 185 isolates (22.8% of total strains) had reduced susceptibility to beta-lactams due to modification of the target associated or not with beta-lactamase production. When beta-lactamase was produced, the MICs of amoxicillin increased, but the activity of the other antibiotics was unchanged. Low BLNAR strains showed an increase in the MICs of all beta-lactams. This increase was weak and variable according to beta-lactams. Pristinamycin and telithromycin activities were unchanged against these strains. Two strains were resistant to erythromycin. CONCLUSIONS: Theses results show that both beta-lactamase and modifications of the target are widespread among H. influenzae strains isolated in France. Cefpodoxime remains the most active compounds against H. influenzae, whatever the resistance mechanisms, followed by pristinamycin, telithromycin, and co-amoxiclav.

Changes in olfactory inputs modify the energy balance response to short days in male gray mouse lemurs.

The role of olfaction/olfactory cues on photoperiodic responses was assessed in Malagasy primate, the gray mouse lemur. When exposed to short photoperiod (SP), this primate demonstrates rapid changes in energy balance as adaptive anticipatory response for winter survival. To follow early changes induced by SP exposure, body mass, food intake, resting metabolism (RMR) and free thyroxin levels in plasma (T4) were measured in males abruptly transferred to SP: six intact males (controls), eight males that underwent bilateral olfactory removal (BOX) and eight males exposed to male urinary cues (U-exposed). To assess the effect of SP exposure, two other groups were maintained for 6 weeks under LP: six controls and six BOX males. Whereas all studied parameters remained constant in controls and BOX males maintained under LP, exposure to SP led to different responses according to groups. In controls, SP exposure led to a regular increase in body mass and after 4 weeks under SP, plasma T4 levels, food consumption and RMR significantly decreased. Even if BOX males demonstrated hyperphagic patterns regardless of the photoperiod, an increase in body mass was also induced by SP exposure but without changes in RMR or food intake that were body mass-dependent. In U-exposed males, body mass gain was significantly reduced while food intake and RMR remained high. In both BOX and U-exposed males, SP exposure led to a transient but high increase in T4 levels compared to controls. These results suggest that olfaction/olfactory cues may delay the SP-mediated changes in energy balance.

Genotyping of type b Haemophilus influenzae strains, comparison of strains collected before and during vaccine availability.

OBJECTIVE AND METHOD: Five hundred and seventy-eight strains of type b Haemophilus influenzae (521 isolated in children, and 57 in adults) were compared using pulsed-field gel electrophoresis (PFGE) to assess strain evolution and to study the impact of the generalization of anti-Haemophilus b (anti-Hib) vaccination in France. Among these strains, 398 (including 342 from meningitis) were isolated in 1985-1992 (pre-vaccination era), 39 (including 31 from meningitis) in 1993 (year of the generalization of anti-Hib vaccination), and 141 (including 50 from CSF) in 1994-2001 (vaccination era). RESULTS: A total of 102 PFGE patterns (patterns for 1-101 isolates) were obtained after SmaI restriction of the 578 strains. The strains isolated in children were distributed in 96 patterns, and those isolated in the adult in 34 patterns. The strains isolated during the pre-vaccination era presented 94 patterns. During the vaccination era, 50% of the patterns disappeared and 12 new patterns (11.7%) including 15 strains were observed. The strains belonging to the new patterns (including the two observed in 1993) were isolated in adults (n=7) from blood culture and bronchial secretions, and children (n=9) from CSF, blood culture, and bronchial secretions. In children, among the strains associated to vaccination failure, two presented with a new pulsotype. CONCLUSION: There is no evidence that the vaccination program brought about any drastic modifications in the type b strains causing meningitis or in the other type b strains in circulation whether in adults or children.

[Epidemiology of Haemophilus influenzae strains identified in 2001 in France, and assessment of their susceptibility to beta-lactams]. / Epidémiologie et évaluation de la sensibilité aux bêta-lactamines des souches de Haemophilus influenzae isolées en 2001 en France.

UNLABELLED: The aim of this study was to describe the epidemiology of H. influenzae strains collected in 2001 at the National Reference Center and to evaluate their susceptibility to beta-lactams. METHODS: The demographic characteristics were recorded for each strain, then were determined their capsular serotyping (slide agglutination with specific antisera), as well as their beta-lactamase production (chromogenic cephalosporin test, Nitrocefin), and their MICs (agar dilution method on Haemophilus Test Medium) for amoxicillin (AMX), co-amoxiclav (AMC), cefpodoxime (CPD), cefaclor (CEC), cefuroxime (CXM), and cefotaxime (CTX). RESULTS: 41.3% of the 752 strains were identified in bronchial secretions, 20.6% in conjunctivitis, 11.3% in otitis media, and 11% in blood cultures. 96.3% of the strains were not capsulated and 3.7% were of type b, d, e or f. 33.8% of the strains were beta-lactamase producers (TEM type), 45.8% of these were identified in otitis pus and 27.7% in bronchial secretions. One hundred and forty-two strains (18.9%) presented reduced susceptibility to beta-lactams (modification of target) associated or not with bla+. MICs 50/90 against bla+ strains were: AMX 1/32, AMC 0.12/1, CTX 0.007/0.03, CPD 0.03/0.12, CEC 1/64, CXM 0.25/1. Against low BLNAR and bla+ strains, MICs 50/90 were: AMX 2/32, AMC 0.25/2, CTX 0.015/0.06, CPD 0.06/0.25, CEC 4/64, CXM 0.25/4. And against low BLNAR strains MICs 50/90 were: AMX 0.25/8, AMC 0.25/8, CTX 0.015/0.12, CPD 0.06/0.50, CEC 4/32, CXM 0.25/4. CONCLUSIONS: Both bla+ and modifications of PBP are widespread among strains isolated in France. CTX, and CPD remain the most active compounds whatever the resistance mechanisms.

Factors affecting the daily rhythm of body temperature of captive mouse lemurs (Microcebus murinus).

Microcebus murinus, a small nocturnal Malagasy primate, exhibits adaptive energy-saving strategies such as daily hypothermia and gregarious patterns during diurnal rest. To determine whether ambient temperature (T(a)), food restriction and nest sharing can modify the daily body temperature (T(b)) rhythm, T(b) was recorded by telemetry during winter in six males exposed to different ambient temperatures (T(a) = 25, 20, 15 degrees C) and/or to a total food restriction for 3 days depending on social condition (isolated versus pair-grouped). At 25 degrees C, the daily rhythm of T(b) was characterized by high T(b) values during the night and lower values during the day. Exposure to cold significantly decreased minimal T(b) values and lengthened the daily hypothermia. Under food restriction, minimal T(b) values were also markedly lowered. The combination of food restriction and cold induced further increases in duration and depth of torpor bouts, minimal T(b) reaching a level just above T(a). Although it influenced daily hypothermia less than environmental factors, nest sharing modified effects of cold and food restriction previously observed by lengthening duration of torpor but without increasing its depth. In response to external conditions, mouse lemurs may thus adjust their energy expenditures through daily modifications of both the duration and the depth of torpor.

[Study of susceptibility of Haemophilus influenzae to beta-lactams by using HTM gelose (Haemophilus test medium)]. / Etude de la sensibilité de Haemophilus influenzae aux bêtalactamines par utilisation de la gélose HTM (Haemophilus test medium).

HTM agar was used for in vitro study of bêta-lactam antibiotics activity on H. influenzae. Tested strains belong to the three ampicillin phenotypes: sensitive, betalactamase production and ampicillin resistance without production of betalactamase. Using 2 micrograms ampicillin disk, diameters > or = 20 mm and < 20 mm separate ampicillin sensitive and resistant strains. The following zone-size breakpoints could be suggested: ampicillin (10 micrograms) > or = 25 and < 22 mm; amoxicillin (25 micrograms) > or = 26 mm and < 23 mm; ampicillin/sulbactam (10/10 micrograms) > or = 25 mm and < 22 mm; amoxicillin/clavulanic acid (20/10 micrograms) > or = 26 mm and < 23 mm; cefaclor (30 micrograms) > or = 25 mm and < 20 mm; cefuroxime (10 micrograms) > or = 22 mm and < 19 mm; cefixime (10 micrograms) and cefpodoxime (10 micrograms) > or = 26 mm; cefotaxime (30 micrograms) et ceftriaxone (30 micrograms) > or = 30 mm. The zone-size breakpoints concentrations, distribution of bacterial populations, mechanisms of resistance. In vitro study may screen for ampicillin resistance mechanisms.

[Study of susceptibility of Haemophilus influenzae to antibiotics (other than beta-lactams) by using HTM gelose (Haemophilus test medium)]. / Etude de la sensibilité de Haemophilus influenzae aux antibiotiques (autres que les bêtalactamines) par utilisation de la gélose HTM (Haemophilus test medium).

HTM agar was used for in vitro study for antibiotics activity (other than beta-lactams) on H. influenzae. Tested strains belong to various phenotypes. The zone-size breakpoints were determined according to breakpoints concentrations, distribution of bacterial populations and mechanism of resistance. The following zone-size breakpoints could be suggested: chloramphenicol (30 micrograms) > or = 28 and < 24 mm; kanamycin (30 UI) > or = 18 and < 15 mm; gentamicin (10 UI) > or = 16 and < 14 mm; tetracycline (30 UI) > or = 23 and < 18 mm; doxycycline (30 UI) > or = 20 and < 14 mm; minocycline (30 UI) > or = 20 mm; rifampicin (30 micrograms) > or = 24 and < 20 mm; pristinamycin (15 micrograms) > or = 20 mm; erythromycin (15 UI) > or = 22 and < 18 mm; ciprofloxacin (5 micrograms) > or = 30 mm; trimethoprim and co-trimoxazole > or = 24 and < 20 mm.

[in vitro activity of telithromycin against Haemophilus influenzae]. / Evaluation de l'activité in vitro de la télithromycine sur Haemophilus influenzae.

The aim of this study was to evaluate the in vitro activity of telithromycin against 142 strains of Haemophilus influenzae using determination of MICs by agar dilution method and to evaluate the correlation between MICs and inhibition diameter zones obtained by disk diffusion testing. MIC50 and MIC90 of telithromycin were 1 and 2 mg/L respectively. Telithromycin activity against H. influenzae was similar to that of azithromycin, superior to erythromycin and clarithromycin and irrespective of the susceptibility to betalactams. Distribution of diameter zones showed a similar pattern to that of MICs but correlation between MICs and diameter zones was poor with correlation coefficients inferior to 0.5 whatever the agar media used.

The activity of clarithromycin and its 14-hydroxy metabolite against Haemophilus influenzae, determined by in-vitro and serum bactericidal tests.

The in-vitro activity of clarithromycin and its main metabolite 14-hydroxy clarithromycin against Haemophilus influenzae was evaluated by determining minimum inhibitory and minimum bactericidal concentrations. The 14-hydroxy metabolite was more active than the parent compound against H. influenzae. The activity of the parent compound/metabolite combination was evaluated against 20 strains of H. influenzae by the chequerboard technique. The combination was synergistic against seven isolates in terms of fractional bactericidal concentration index and against five isolates in terms of fractional inhibitory concentration index; the combination demonstrated additive activity against the remaining strains. Serum bactericidal activity against H. influenzae was measured in sera from six healthy volunteers who had received 250 mg clarithromycin by mouth. The area under the serum bactericidal activity curve correlated with the area under the curves for clarithromycin and 14-hydroxy clarithromycin, and with the in-vitro susceptibility of the strains tested. Serum bactericidal activity was detected at 30 min after dosing and lasted for 5-6 h.

[Sensitivity of Kingella kingae to antibiotics]. / Sensibilité aux antibiotiques de Kingella kingae.

Kingella kingae is a small Gram negative rod of the Neisseriaceae family, formerly called Moraxella kingae. This microorganism is found occasionally in the oral cavity and is capable of causing infections. We report three cases of septic arthritis in children due to K. kingae. In vitro susceptibility of the recovered strains was tested using determination of MICs in agar. The strains were susceptible to penicillin, ampicillin, ticarcillin, cephalothin, cefotaxime, gentamicin, chloramphenicol, tetracycline, trimethoprim-sulfamethoxazole, and pefloxacin, less susceptible to erythromycin and resistant to lincomycin (MIC 32 mg/l).