Staphylococcal cassette chromosome mec characterization of methicillin-resistant Staphylococcus aureus strains isolated at the military hospital of Constantine/Algeria.

Staphylococcal cassette chromosome mec is a genetic mobile element that carries the gene mecA mediating the methicillin resistance in staphylococci. The aim of this study is to type the Staphylococcal cassette chromosome mec (SCCmec) in 64 non-redundant methicillin-resistant Staphylococcus aureus (MRSA) strains recovered at the military hospital of Constantine (Algeria) between 2005 and 2007. Methicillin resistance was detected by oxacillin and cefoxitin discs and PBP2a test, and then confirmed by mecA PCR. The SCCmec complex types were determined by real time PCR. The analysis showed that 50 isolates were hospital acquired (HA-MRSA) and 14 were community-acquired (CA-MRSA). SCCmec type IV and V (traditionally attributed to CA-MRSA) were harbored by both HA-MRSA and CA-MRSA, while SCCmec type I, II and III were not recorded. These findings motivate more investigations to be carried on HA-MRSA in our hospital and other national health care centers.

Reprint of: Serotyping and antibiotic susceptibility of Streptococcus pneumoniae strains isolated in Algeria from 2001 to 2010.

INTRODUCTION: Pneumococcal infections are a major public health problem because of the virulence of this bacterium and its ability to develop resistance. MATERIAL AND METHOD: Two hundred and ninety-four strains of Streptococcus pneumoniae were isolated from sterile (56.8%) and non-sterile samples (43.2%), from January 2001 to July 2010. RESULTS: The interpretation of antibiotic susceptibility testing, according to CLSI criteria (M100-S21 2011), yielded a 25.2% overall resistance to penicillin, with 23.5% of strains isolated from CSF (meningitis), and only 1.7% in other samples. Resistance to cefotaxime was 8.1% (including 4.4% at a high level). The most common serotypes were: 14 (19.5%), 23F (9.7%), 6B (9.3%), 19F (5.4%), and serotype 1 (5%). The percentage of these serotypes isolated from normally sterile sites in children under 5 years of age was 31.25% for 14, 10.4% for 23F, 8.3% for 19F, 6.25% for 6B, and 4.2% for serotype 1. The theoretical vaccinal coverage against invasive infections in children under 2 years of age was 61.5%, 69.2%, and 76.9% for the 7-valent, 10-valent, and 13-valent conjugate vaccines, respectively. Penicillin non-susceptible Streptococcus pneumoniae (PNSP) strains accounted for 67.1, 68.6, and 72.8% for each of these three vaccines. CONCLUSION: There was a variation of serotype rates compared to previous studies. The increase in pneumococcal antibiotic resistance is concerning, particularly for the treatment of pneumococcal infections in children and infants. Pneumococcal vaccination is not compulsory yet in Algeria.

Serotyping and antibiotic susceptibility of Streptococcus pneumoniae strains isolated in Algeria from 2001 to 2010.

INTRODUCTION: Pneumococcal infections are a major public health problem because of the virulence of this bacterium and its ability to develop resistance. MATERIAL AND METHOD: Two hundred and ninety-four strains of Streptococcus pneumoniae were isolated from sterile (56.8%) and non-sterile samples (43.2%), from January 2001 to July 2010. RESULTS: The interpretation of antibiotic susceptibility testing, according to CLSI criteria (M100-S21 2011), yielded a 25.2% overall resistance to penicillin, with 23.5% of strains isolated from CSF (meningitis), and only 1.7% in other samples. Resistance to cefotaxime was 8.1% (including 4.4% at a high level). The most common serotypes were: 14 (19.5%), 23F (9.7%), 6B (9.3%), 19F (5.4%), and serotype 1 (5%). The percentage of these serotypes isolated from normally sterile sites in children under 5 years of age was 31.25% for 14, 10.4% for 23F, 8.3% for 19F, 6.25% for 6B, and 4.2% for serotype 1. The theoretical vaccinal coverage against invasive infections in children under 2 years of age was 61.5%, 69.2%, and 76.9% for the 7-valent, 10-valent, and 13-valent conjugate vaccines, respectively. Penicillin non-susceptible Streptococcus pneumoniae (PNSP) strains accounted for 67.1, 68.6, and 72.8% for each of these three vaccines. CONCLUSION: There was a variation of serotype rates compared to previous studies. The increase in pneumococcal antibiotic resistance is concerning, particularly for the treatment of pneumococcal infections in children and infants. Pneumococcal vaccination is not compulsory yet in Algeria.

Molecular characterization of methicillin-resistant Staphylococcus aureus isolates in Algeria.

INTRODUCTION: The epidemiology of Staphylococcus aureus has changed radically since 1999, in particular, methicillin-resistant S. aureus (MRSA), originally restricted to hospital, has emerged as a significant pathogen in the community, and true community-acquired MRSA (CA-MRSA) infections have been reported in patients with no clear risk factors. CA-MRSA strains frequently produce Panton-Valentine leukocidin (PVL). OBJECTIVES: The objectives of this study were: (i) to monitor the prevalence of PVL and toxic shock syndrome toxin-1 (TSST-1) isolates MRSA; (ii) to identify the staphylococcal cassette chromosome (SCCmec) types of MRSA isolates. MATERIAL AND METHODS: Sixty-four isolates, collected between 2005 and 2007 in Didouche Mourad hospital of Algeria. The isolates were identified by conventional methods. The antibiotic susceptibility of the isolates was performed using the disk diffusion method and automat Vitek2. The presence of gene mecA, the genes encoding SCCmec type, PVL and TSST-1 toxins were investigated by real-time PCR. RESULTS: All strains were gene mecA positives, 32 (50%) harboured SCCmec IV type, 28 (43.75%) harboured SCCmec V type. 19 (29.68%) have been identified positive for the leukocidin toxin (PVL), they harboured SCCmec type IV. The virulence factor TSST-1 was not present among these isolates. CONCLUSION: These results show a high prevalence of PVL-positive H-MRSA in our wards.