Penicillin

About: Penicillin is a research topic. Over the lifetime, 17916 publications have been published within this topic receiving 368480 citations. The topic is also known as: penicillin antibiotic & PCN.

Prevalence of resistance to MLS antibiotics in 20 European university hospitals participating in the European SENTRY surveillance programme

Abstract: Macrolide, lincosamide and streptogramin (MLS) antibiotics are chemically distinct inhibitors of bacterial protein synthesis. Resistance to MLS antibiotics may be constitutive or inducible. The purpose of this study is to update our understanding of the prevalence of different forms of MLS resistance in Europe. The analysis of 3653 clinical pneumococcal, staphylococcal and enterococcal isolates exhibited an average percentage of 21.3% and 6.2% intermediate and high-level penicillin-resistant Streptococcus pneumoniae, 21.8% methicillin-resistant S t a p h y l o- coccus aureus and 11% vancomycin-resistant Enterococcus faecium. Geographical differ- ences in erythromycin and clindamycin resistance in isolates of S. pneumoniae and S. aureus strongly reflect geographical variations in susceptibility to penicillin and methicillin, respec- tively. A very narrow range of MICs was obtained with quinupristin/dalfopristin, with no S. pneumoniae, S. aureus and E. faecium isolate having an MIC of >4 mg/L, indicating a possible role of quinupristin/dalfopristin in the treatment of infections by multi-resistant Gram-positive bacteria.

Infections due to penicillin-resistant pneumococci. Clinical, epidemiologic, and microbiologic features.

Abstract: Pneumococcal infection remains a common cause of serious morbidity and mortality throughout the world. Until recently, clinical isolates of pneumococci that were penicillin resistant were rare. However, 4% to 5% of the clinical isolates in the United States were recently found to be either intermediately resistant or highly resistant to penicillin. Clinicians in every field of medicine must therefore be better informed regarding penicillin-resistant pneumococcal infections to minimize their attendant morbidity and mortality and increase compliance with preventive measures. We reviewed the molecular, genetic, and epidemiologic aspects of penicillin-resistant pneumococcal infections, with emphasis on their microbiologic and clinical features.

Virulence Gene Profiles of Multidrug-Resistant Pseudomonas aeruginosa Isolated From Iranian Hospital Infections.

Abstract: Background: The most common hospital-acquired pathogen is Pseudomonas aeruginosa. It is a multidrug resistant bacterium causing systemic infections. Objectives: The present study was carried out in order to investigate the distribution of virulence factors and antibiotic resistance properties of Pseudomonas aeruginosa isolated from various types of hospital infections in Iran. Patients and Methods: Two-hundred and seventeen human infection specimens were collected from Baqiyatallah and Payambaran hospitals in Tehran, Iran. The clinical samples were cultured immediately and samples positive for P. aeruginosa were analyzed for the presence of antibiotic resistance and bacterial virulence genes using PCR (polymerase chain reaction). Antimicrobial susceptibility testing was performed using disk diffusion methodology with Mueller–Hinton agar. Results: Fifty-eight out of 127 (45.66%) male infection specimens and 44 out of 90 (48.88%) female infection specimens harbored P. aeruginosa. Also, 65% (in male specimens) and 21% (in female specimens) of respiratory system infections were positive for P. aeruginosa, which was a high rate. The genes encoding exoenzyme S (67.64%) and phospholipases C (45.09%) were the most common virulence genes found among the strains. The incidences of various β-lactams encoding genes, including bla TEM , bla SHV , bla OXA , bla CTX-M , bla DHA, and bla VEB were 94.11%, 16.66%, 15.68%, 18.62%, 21.56%, and 17.64%, respectively. The most commonly detected fluoroquinolones encoding gene was gyrA (15. 68%). High resistance levels to penicillin (100%), tetracycline (90.19%), streptomycin (64.70%), and erythromycin (43.13%) were observed too. Conclusions: Our findings should raise awareness about antibiotic resistance in hospitalized patients in Iran. Clinicians should exercise caution in prescribing antibiotics, especially in cases of human infections.

Mechanism of Resistance to Antibiotic Synergism in Enterococci

Abstract: Enterococci exhibit two types of resistance to streptomycin. Moderately high-level resistance is observed in most naturally occurring strains and can be overcome by simultaneous exposure to penicillin. In addition, very high-level resistance is found in those strains against which penicillin plus streptomycin fail to produce synergism in vitro. To study the mechanism of streptomycin resistance in enterococci, ribosomes from a wild-type strain and from a highly streptomycin-resistant mutant were isolated, characterized, and studied in an in vitro amino acid incorporation system. The ribosomes from the organism with moderately high-level streptomycin resistance were sensitive to streptomycin in vitro, suggesting that this type of resistance is caused by failure of streptomycin to reach the ribosomes. Very high-level resistance (and lack of penicillin-streptomycin synergism), on the other hand, appears to be due to ribosomally mediated streptomycin resistance.