Résumé
Background: Streptococcus agalactiae or group B streptococcus [GBS] is a normal flora of the vagina of healthy women. It emerged as the leading cause of neonatal invasive infections
The purpose of this study was to detect the magnitude of GBS neonatal infection and colonization and to compare between invasive and colonizing strains as regard antibiotic susceptibility patterns, serotypes and virulence factors
Methods: A total of 145 neonatal blood samples and 95 vaginal swabs from pregnant women were collected in the present study. Invasive GBS were isolated from neonates by blood cultures. Colonizing GBS isolates were identified by vaginal swabbing of pregnant women using Todd-Hewitt selective broth medium, supplemented with gentamicin [8microg/mL] and nalidixic acid [15microg/mL]. Antibiotic sensitivities and serotyping by latex agglutination were done. GBS virulence factors were studied including detection of beta-haemolysin production, CAMP test on blood agar plates, C5a peptidase production encoded by scpB gene and presence of highly virulent GBS ST-17 clone
Results: GBS were isolated from 11.7% of neonates [17/145] and from 18.9% [18/95] of vaginal swabs. Resistance patterns of isolated invasive GBS were 29.4 %, and 17.6% for erythromycin and clindamycin respectively. Among invasive and colonizing GBS isolates, serotype III was the most common. GBS neonatal sepsis was significantly associated with respiratory distress, pneumonia, use of mechanical ventilation and use of nasal continuous positive airway pressure. All of GBS isolates were CAMP test positive. Hemolytic GBS were 91.4% [32/35] of isolates. The scpB gene was detected in 88.2% and 88.9% of invasive and colonizing GBS isolates respectively while presence of ST-17 clone was significantly associated with invasive GBS isolates with P value of 0.002
Résumé
Background: trimethoprim/sulfamethoxazole [['MPISMX] has been the antimicrobial of choice for treatment of Stenotrophomonas malt philia [S. malt philia] infections. Several reports have shown that the prevalence of strains resistant to TMP/SMX is increasing. We investigated prevalence, risk factors and sulfamethoxazole resistance determinants of TMPISMX resistant S. malt philia in our geographic location
Methods: this study was conducted from January, 2009 till March, 2010 on 625 patients admitted to intensive care units [ICUs] in Mansoura University Hospitals [MUHs]. Nosocomial S. malt philia infections were detected in 90 samples. Antimicrobial susceptibilities were determined using the disk diffusion method. PCR was. Conducted for the detection of sull and sul2
Results: out of 90 S. malt philia isolates, 22 [24.4%] revealed resistances to TMPISMX Significant risk factors were: duration of ICU stay [P = 0.018], antibiotic treatment [P = 0.002] specifically Carbapenems [P = 0.035] and fluoroquinolones [P < 0.001] and duration of antibiotic treatment. All TMPISMX resistant S. malt philia isolates were positive for sull gene. None of the isolates carried sul2
Conclusion: the isolation of TMP/SMX resistant S. malt philia at our geographic location is alarming. Strategies to prevent S. malt philia infection should be encouraged. The resistance of S. malt philia isolates to TMP/SMX is due to sull rather than to sul2