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To determine the occurrence of <i>Enterobacter sakazakii</i> and other Enerobateriaceae in commercial powdered infant formula (PIF), 185 packages of PIF from different manufacturers, supermarkets and drug-stores in Abidjan were analyzed. Ten g of sample was homogenized in 90 ml of buffered peptone water (PBW, Biorad, Paris) for further studies. Enterobacteriaceae (coliforms) were enumerated according to French Association of Standardization methods. <i>E. sakazakii</i> was detected according to Kandhai’s method. Bacteria were identified using API20 system. Thirty-eight samples (20.5%) were positive for Enterobacteriaceae. Twenty-four samples (13%) yielded <i>Enterobacter sakazakii</i>. Other Enterobacteriaceae isolated included <i>Pantoea spp.</i> 21 (11.5%), <i>Klebsiella pneumoniae subsp. Pneumonia</i> 8 (4.3%), <i>Citrobacter diversus</i> 1 (0.5%), <i>Citrobacter freundii</i> 1 (0.5%), </i>Enterobacter cloacae</i> 1 (0.5%), <i>Salmonella reading</i> 1 (0.5%), <i>Serratia ficara</i> 1 (0.5%) <i>Serratia odorifera</i> 1 (0.5%). This study is the first report to describe the contamination of PIF from Abidjan with <i>E. sakazakii</i> and several other Enterobacteriaceae that could be opportunistic pathogens. Therefore, well-controlled studies need to be conducted to assess the extent of risk associated with contaminated PIF for infants in Abidjan

Rhodococcus equi is a facultative, intracellular, Gram-positive coccobacillus, increasingly reported in pneumonia of AIDS-infected patients. We investigated killing resistance properties of human R. equi virulent and avirulent human strains. Avirulent beta-lactam-susceptible strains had lower intracellular colony forming units after 45 min incubation in murine macrophages J774 and human monocyte-macrophage TPH-1 than those of virulent strains. Only virulent beta-lactam-resistant strains persisted within macrophages for at least 18 min only. A beta-lactam-resistant mutant was obtained from a beta-lactam-susceptible strain after selection in a penicillin G-containing culture medium. This mutant strain, like the natural virulent strains, persisted within macrophages, harboured cell-associated appendages, produced phage-like particles and induced, after its intravenous inoculation, a chronic infection in BALB/c nude mice. Supernatant culture of virulent strains transferred partial macrophage-killing resistance properties to avirulent strains. The same supernatant was toxic for L-929, HeLa and Vero cell cultures. These supernatant effects were heat-inactivated, trypsin-inactivated and did not seem to be linked to phage-like particle presence. These data argue that virulence, beta-lactam-resistance, and macrophage-killing resistance are associated in human R. equi isolates. Moreover, only virulent strains produced uncharacterized toxic factors.

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Les mycoplasmes sont des bactéries du tractus uro-génital souvent associés à l'infertilité masculine. Au plan thérapeutique, des résistances acquises vis-à-vis des antibiotiques ont été rapportées. Ce travail avait pour objectif de déterminer le niveau de sensibilité des mycoplasmes uro-génitaux isolés au cours de la spermoculture. L'étude rétrospective, a porté sur 313 mycoplasmes identifiés grâce au kit Mycoplasma IST 2 (Biomérieux, Réf 42 505). Ce kit permet la quantification différentielle, l'identification de Ureaplasma urealyticum, et Mycoplasma hominis, ainsi que l'étude de la sensibilité à neuf antibiotiques (josamycine, azithromycine, érythromycine, clarithromycine, pristinamycine, tétracycline, doxycycline, ofloxacine etciprofloxacine). Ureaplasma urealyticum a été identifié dans 245 échantillons (78,3%) et Mycoplasma hominis dans 27 (8,6%). La co-infection (Ureaplasma urealyticum/Mycoplasma hominis) a été retrouvée chez 41 patients (13,1%). La josamycine était active sur l'ensemble des germes avec des sensibilités respectives de 90,2% et 92,6% pour Ureaplasma urealyticum et pour Mycoplasma hominis. L'activité des cyclines sur Ureaplasma urealyticum était bonne tandis que celle des fluoroquinolones était médiocre. La pristinamycine était efficace sur Mycoplasma hominis (70%). L'étude a montré que la josamycine était active sur l'ensemble des mycoplasmes, les cyclines conservaient une bonne efficacité sur Ureaplasma urealyticum contrairement aux fluoroquinolones. Ces variations de sensibilité justifient l'intérêt de l'identification des deux espèces et l'étude de la sensibilité pour une bonne prise en charge de ces infections.