Preliminary evaluation of a new kit for differentiation of Mycobacterium tuberculosis complex species using Speed-Oligo MTBC.

We present the first evaluation of a novel molecular assay, the Speed-Oligo Mycobacterium tuberculosis complex (SO-MTBC), which is based on PCR combined with a dipstick for the differentiation of M. tuberculosis complex (MTBC) members. The results of this assay were compared with findings obtained using the Genotype MTBC assay. In this study, 189 strains of MTBC isolates from 2011 to 2014 were evaluated to determine the MTBC species. Most (174, 92 %) of the strains were identified as M. tuberculosissensu stricto, 7 (3.7 %) as Mycobacteriumbovis, 5 (2.6 %) as M. bovis bacillus Calmette-Guérin, 2 (1.1 %) as Mycobacteriumafricanum and 1 (0.5 %) as Mycobacteriumcaprae; no strains belonged to Mycobacteriummicroti and Mycobacteriumcanettii subsp. The concordance κ coefficient obtained was 0.96 with the results of the Genotype MTBC assay. SO-MTBC may represent a fast and easy-to-use alternative for differentiating among MTBC subspecies in laboratories with standard equipment.

Molecular characterization and antimicrobial susceptibility of hemolytic Streptococcus agalactiae from post-menopausal women.

PURPOSE: Streptococcus agalactiae (Group B streptococcus, GBS) is increasingly recognized as a pathogen in adult populations, including the elderly. Appropriate treatment involves antibiotics. An alternative to this strategy would be the administration of a polysaccharide vaccine therefore the capsular serotypes and molecular characterization of circulating strains needs to be known. Few studies have been conducted in this population. METHODS: One hundred and seven GBS isolates collected from vagino-rectal swabs from 600 post-menopausal women were analysed for their capsular type, antimicrobial resistance and genetic relatedness (multilocus sequence typing, MLST). RESULTS: The colonization rate was 17.8%. Capsular type III was predominant (34.6%), followed by type V (22.4%). The most frequent sequence type (ST) was 19 (23.3%), followed by 23 (18.7%), 1 (16.8%) and 17 (12.1%). Isolates were assembled into three phylogenetic groups from ST-19, ST-23 and ST-17 founders. All isolates were susceptible to penicillin, whereas resistance to erythromycin and clindamycin was recorded in 23.4% and 20.6% of isolates, respectively. CONCLUSIONS: In our setting, the GBS colonization rate in postmenopausal women is similar to that reported in others populations studied. The population structure of these isolates is highly diverse and contains different STs. These data can contribute to the future development of a polysaccharide vaccine for preventing GBS infection in older adults.

Serotipos y patrones de resistencia antibiótica en aislados betahemolíticos deStreptococcus agalactiae de madres colonizadas y recién nacidos con enfermedad invasiva / Serotypes and antibiotic resistance patterns in beta-hemolytic Streptococcus agalactiae isolates in colonized mothers and newborns with invasive disease

INTRODUCCIÓN: Las actuales medidas de prevención frente a la enfermedad neonatal causada por Streptococcus agalactiae, estreptococo del grupoB (EGB), son la realización de un cribado prenatal y la administración de profilaxis antibiótica intraparto con antimicrobianos adecuados. Una alternativa a esta estrategia sería la administración de una vacuna polisacarídica, por lo que es necesario conocer la distribución de serotipos capsulares de las cepas circulantes. MÉTODOS: Se estudiaron 188 cepas procedentes de gestantes del área sanitaria norte de Granada portadoras vaginorrectales de EGB y 24 de recién nacidos con enfermedad neonatal enviadas al laboratorio desde distintos hospitales andaluces. Se realizó antibiograma frente a penicilina, eritromicina y clindamicina siguiendo las normas del Clinical and Laboratory Standards Institute (CLSI), y se determinó su serotipo capsular mediante 2 métodos: aglutinación con partículas de látex y métodos moleculares. RESULTADOS: De las 188 cepas de S.agalactiae pertenecientes a mujeres embarazadas, se obtuvo una concordancia en los resultados del 80,8% entre ambas técnicas. Se detectó resistencia a eritromicina y clindamicina en el 16,5 y el 10,1% de cepas, respectivamente. En las cepas neonatales, en el 95,8% de los aislados los resultados obtenidos por ambas técnicas fueron coincidentes. Las tasas de resistencia frente a eritromicina y clindamicina fueron del 8,3 y del 4,1%, respectivamente. En ambos grupos de aislados el serotipo más frecuente fue el III y el más relacionado con resistencia frente a antimicrobianos, el V. CONCLUSIÓN: Se deberían realizar más estudios epidemiológicos que permitan continuar con una vigilancia de los serotipos causantes de enfermedad invasiva así como sus patrones de sensibilidad antibiótica utilizando métodos sensibles y específicos

INTRODUCTION: Current preventive measures against neonatal disease caused by Streptococcus agalactiae (GBS) are prenatal screening and intrapartum antibiotic prophylaxis with appropriate antimicrobials. An alternative to this strategy would be the administration of a polysaccharide vaccine as the distribution of capsular serotypes of circulating strains needs to be known. METHODS: A study was made of 188 strains from pregnant women carrying GBS and 24 newborns with neonatal disease. Susceptibility testing was performed with penicillin, erythromycin and clindamycin following CLSI standards, and capsular serotype was determined by two methods: latex agglutination and PCR. RESULTS: Of the 188 strains of S.agalactiae from the pregnant women, there was 80.8% agreement in the results between the two techniques. Resistant to erythromycin and clindamycin was found in 16.5% and 10.1%, respectively. For neonatal strains, 95.8% of the results obtained by the two techniques were identical. The rates of resistance to erythromycin and clindamycin were 8.3% and 4.1%, respectively. In both groups, most frequently isolated serotype was III, and the most related to antimicrobial resistance serotype was V. CONCLUSIÓN: Epidemiological studies are necessary to continue surveillance of serotypes causing invasive disease and its antibiotic sensitivity patterns using sensitive and specific methods

[Serotypes and antibiotic resistance patterns in beta-hemolytic Streptococcus agalactiae isolates in colonized mothers and newborns with invasive disease]. / Serotipos y patrones de resistencia antibiótica en aislados betahemolíticos de Streptococcus agalactiae de madres colonizadas y recién nacidos con enfermedad invasiva.

INTRODUCTION: Current preventive measures against neonatal disease caused by Streptococcus agalactiae (GBS) are prenatal screening and intrapartum antibiotic prophylaxis with appropriate antimicrobials. An alternative to this strategy would be the administration of a polysaccharide vaccine as the distribution of capsular serotypes of circulating strains needs to be known. METHODS: A study was made of 188 strains from pregnant women carrying GBS and 24 newborns with neonatal disease. Susceptibility testing was performed with penicillin, erythromycin and clindamycin following CLSI standards, and capsular serotype was determined by two methods: latex agglutination and PCR. RESULTS: Of the 188 strains of S.agalactiae from the pregnant women, there was 80.8% agreement in the results between the two techniques. Resistant to erythromycin and clindamycin was found in 16.5% and 10.1%, respectively. For neonatal strains, 95.8% of the results obtained by the two techniques were identical. The rates of resistance to erythromycin and clindamycin were 8.3% and 4.1%, respectively. In both groups, most frequently isolated serotype was iii, and the most related to antimicrobial resistance serotype was v. CONCLUSION: Epidemiological studies are necessary to continue surveillance of serotypes causing invasive disease and its antibiotic sensitivity patterns using sensitive and specific methods.