Prevalence and Antimicrobial Susceptibility of Genital Mycoplasmataceae in Korean Women: Correlation between Phenotypic Test and Resistance Genes / 대한임상미생물학회지

BACKGROUND: While 7.6% of cultured genital Mycoplasmataceae was identified as Ureaplasma urealyticum, most of them were Ureaplasma parvum (80.3%). This is the first study differentiating between these two species. We investigated the prevalence and antimicrobial resistance of genital Mycoplasmataceae in Korean women. METHODS: A total of 150 specimens submitted to the laboratory for culture of M. hominis and Ureaplasma spp. were included. Detection and antimicrobial susceptibility tests were performed with the Mycoplasma IST2 kit (bioMérieux, France). The identification of Ureaplasma spp. was performed by PCR, and mutations in drug resistance genes were investigated by PCR and sequencing. RESULTS: In total, 66 specimens (44.0%) were positive for genital Mycoplasmatacea: U. parvum, 53 (80.3%); U. urealyticum, 5 (7.6%); M. hominis, 2 (3.0%); mixed infection, 6 (9.1%). Susceptibilities of Ureaplasma spp. to erythromycin, azithromycin, clarithromycin, and doxycycline were 86.0%, 80.7%, 98.2%, and 94.7%, respectively. The susceptibility of Ureaplasma spp. to ofloxacin and ciprofloxacin was 47.4% and 17.5%, respectively. The S83L mutation was found in the ParC subunit of the ofloxacin-resistant (5/7, 71.4%) and the ciprofloxacin-resistant isolates (7/14, 50.0%). One M. hominis isolate showed resistance to erythromycin, azithromycin, and clarithromycin but susceptibility to josamycin, pristinamycin, fluoroquinolones, and tetracyclines. CONCLUSION: The prevalence of genital Mycoplasmataceae in Korean women was 44.0%; most of them were identified as U. parvum. As more than 10% of Ureaplasma spp. showed non-susceptibility to erythromycin and azithromycin (15.5%, 20.7%), a susceptibility test is needed prior to use of these antibiotics. Further study is needed about the clinical features of infections caused by U. urealyticum vs. U. parvum and their associated resistance mechanisms.

Optimization of fermentation conditions for pristinamycin production by immobilized Streptomyces pristinaespiralis using response surface methodology

Response surface methodology was used to optimize the fermentation conditions for the production of pristinamycin by immobilization of Streptomyces pristinaespiralis F213 in shaking flask cultivation. Seed medium volume, fermentation medium volume and shaking speed of seed culture were found to have significant effects on pristinamycin production by the Plackett-Burman design. The steepest ascent method was adopted to approach the vicinity of optimum space, followed by central composite design for further optimization. A quadratic model was built to fit the pristinamycin production. The optimum conditions were found to be seed medium volume of 29.5 ml, fermentation medium volume of 28.8 ml, and shaking speed of seed culture at 204 rpm. At the optimum conditions, a production of 213 mg/l was obtained, which was in agreement with the maximum predicted pristinamycin yield of 209 mg/l. This is the first report on pristinamycins production by immobilized S. pristinaespiralis using response surface methodology.

Antimicrobial Susceptibilities of Ureaplasma urealyticum and Mycoplasma hominis in Pregnant Women / 대한임상미생물학회지

BACKGROUND: Ureaplasma urealyticum and Mycoplasma hominis are associated with an increased risk of pregnancy complications, such as preterm birth and premature membrane rupture. The purpose of this study was to determine the isolation rates and antimicrobial susceptibilities of genital mycoplasma in a sample of pregnant women from Jinju, Korea. METHODS: Vaginal swabs were obtained from 258 pregnant women between 2004 and 2008 and tested for the presence of U. urealyticum and M. hominis at Gyeongsang National University Hospital. The identification and antimicrobial susceptibilities of U. urealyticum and M. hominis were determined with a commercially available kit, the Mycoplasma IST2 Kit (bioMe- rieux, Marcy-l'Etoile, France), and evaluated according to standards set by the Clinical and Laboratory Standards Institute (CLSI). RESULTS: U. urealyticum only was detected in 105 specimens (38.6%), while M. hominis only was detected only in 2 specimens (1.8%). Seven specimens (6.7%) were positive both for U. urealyticum and M. hominis. Susceptibilities of U. urealyticum to azithromycin, erythromycin, clarithromycin, and doxycycline were 75.2%, 82.9%, 88.6%, and 88.6%, respectively, while almost all of the isolates were susceptible to josamycin (99.0%) and pristinamycin (100%). The susceptibility of U. urealyticum to ofloxacin and ciprofloxacin was 56.2% and 15.2%, respectively. CONCLUSION: The rate of isolation of genital mycoplasma in pregnant women was 44.2% in Jinju; most of the mycoplasma were U. urealyticum. U. urealyticum and M. hominis were highly resistant to quinolones, but susceptible to josamycin. Therefore, empirical treatment without prior identification and determination of the antimicrobial susceptibility of genital mycoplasma will fail in many cases.

[Streptococcus agalactiae in nonpregnant adult]

The pathogenic capacity of streptococcus agalactiae or Group B Streptococcus [GBS] has been increasing in nonpregnant adults. We carried out a study about the pathogenic capacity and susceptibility to antibiotics of GBS strains isolated between January 2003 and June 2004 in Farhat Hached hospital of Sousse [Tunisian general hospital]. Identification of strains was carried out according to usual bacteriological characters. Susceptibility of GBS to antibiotics was carried out according to CA-SFM recommendations. During the study period, sixty strains were isolated. They were essentially isolated from the urinary tract [52%] and the skin [36.2%]. Women accounted for 68 percent of the cases. Among the 30 hospitalized patients, 20 [66%] had serious underlying disease. Diabetes mellitus was predominant [80%]. All group B streptococci isolates were susceptible to amoxicillin, penicillin G. vancomycin and to pristinamycin. Sixty four percent of isolates were susceptible to erythromycin. Among the invasive infection, caused by GBS in nonpregnant adults, skin and urinary tract infections were the most common. All isolates were susceptible to amoxicillin, penicillin G, vancomycin and to pristinamycin

Antimicrobianos en Unidades de Cuidados Intensivos: uso empírico / Antimicrobial agents in Intensive Care Units: empirical use

Las infecciones son causa importante de mortalidad en las unidades de cuidados intensivos. Actualmente predominan en Chile las causadas por cocáceas Gram positivas (Staphylococcus aureus resistente a meticilina, Staphylococcus coagulasa negativa y Enterococcus resistente a vancomicina) y en segundo lugar bacilos Gram negativos multiresistentes (Klebsiella pneumoniae). Una indicación antimicrobiana tardía o errada eleva significativamente la letalidad de las infecciones en estas condiciones. La introducción de métodos automatizados de hemocultivos y de técnicas de rápida identificación microbiana permiten emplear antimicrobianos de amplio espectro en una indicación empírica inicial y efectuar rápidos ajustes terapéuticos adecuados a cada situación. Se revisan someramente las bondades y limitaciones de nuevos antimicrobianos potencialmente útiles en estas situaciones: cefepime, carbapenems, nuevas quinolonas, pristinamicina, teicoplanina y linezolid. La indicación de antimicrobianos debe fundamentarse en la epidemiología local de resistencia en las infecciones de origen nosocomial.