Emergence of decreased susceptibility to extended-spectrum cephalosporins in Neisseria gonorrhoeae in India.

Background. In the past, Neisseria gonorrhoeae has developed resistance to antimicrobial agents used for its treatment. Consequently, extended-spectrum cephalosporins form the mainstay of treatment for gonorrhoea. Methods. Samples from 88 patients attending the sexually transmitted diseases clinics from December 2009 to January 2011 in two referral hospitals in New Delhi were studied. Antimicrobial susceptibility testing was done using the disc diffusion method as per the calibrated dichotomous sensitivity technique against the following antibiotics: penicillin (0.5 i.u.), tetracycline (10 μg), nalidixic acid (30 μg), ciprofloxacin (1 μg), spectinomycin (100 μg), ceftriaxone (0.5 μg) and cefpodoxime (10 μg) (Oxoid UK). Azithromycin (15 μg) (Oxoid, UK) was tested as per the guidelines of the Clinical and Laboratory Standards Institute. Minimum inhibitory concentrations were determined using the Etest for penicillin, tetracycline, ciprofloxacin, ceftriaxone, spectinomycin and azithromycin as per the manufacturer’s instruction (Biomerieux, France). Results. Eighteen isolates of Neisseria gonorrhoeae were obtained. Three of these had decreased susceptibility to ceftriaxone and cefpodoxime by the disc diffusion method. The minimum inhibitory concentrations of ceftriaxone for two isolates were 0.064 μg/ml and for one isolate it was 0.125 μg/ml. Conclusion. Higher minimum inhibitory concentrations to extended-spectrum cephalosporins is of concern as it has been shown to precede treatment failure. This may warrant its use in increased/multiple dosages alone or possibly in combination (dual therapy), thereby complicating effective disease control. Our report is in accordance with earlier reports from different parts of the world. Therefore, a continuous surveillance of antimicrobial resistance is crucial to tailor treatment schedules for Neisseria gonorrhoeae in a particular geographical region.

Actividad comparativa in vitro de cefpodoxima en relación a otros antibióticos de uso frecuente, frente a patógenos respiratorios, urinarios y de infecciones de partes blandas / Activity of cefpodoxime against pathogens causing respiratory, urinary or soft tissue infections

Background: Cefpodoxime is a new antimicrobial in the Chilean market, recommended for treatment of respiratory and urinary tract infections. Aim: To study the susceptibility of common pathogens isolated from Chilean patients to cefpodoxime and other antimicrobials. Material and methods: The in vitro activity of cefpodoxime, expressed as Minimal Inhibitory Concentration, was studied in 331 S pneumoniae, H influenzae, M catarrhalis, E coli, S aureus and S pyogenes strains, isolated between 2000 and 2004 from respiratory, urinary and soft tissue infections, respectively. Results: Eleven percent of S pneumoniae isolates were resistant to penicillin, 11% were resistant to cefuroxime and 10% to cefpodoxime. All H influenzae isolates were susceptible to cefpodoxime. No H influenzae isolates were resistant to second or third generation cephalosporines. Four percent of H influenzae isolates were resistant to ampicillin by ß-lactamase production. In contrast 81% of M catarrhalis strains were resistant to ampicillin. Six percent of E coli isolates were resistant to cefpodoxime, 9% to cefuroxime, 11% to cefadroxile and 50% to ampicillin or trimethoprim/sulphamethoxazole. Cefpodoxime was the most active antimicrobial against S pyogenes. Conclusions: Cefpodoxime, recently introduced in Chile, is a good alternative for the treatment of common respiratory and urinary tract infections.

Evaluation of glutathione and ascorbic acid as suppressors of drug-induced lipid peroxidation.

In different sets of experiment lipid peroxidation induction capacity of two drugs, viz., ceftizoxime sodium, a third generation cephalosporin antibiotic, and acyclovir, an antiviral agent, was studied using goat whole blood as the lipid source. Ceftizoxime sodium caused significant extent of lipid peroxidation. Lipid peroxidation being a toxicity mediating process, such observation may be related to the toxic potential of the drug. Insignificant induction of lipid peroxidation was found in case of acyclovir and this is in good agreement with the safety record of the drug. Glutathione and ascorbic acid could significantly reduce ceftizoxime sodium induced lipid peroxidation, suggesting that free radical scavenging action of antioxidants may be exploited by possible antioxidant co-therapy to reduce iatrogenicity of the drug in persons with impaired endogenous antioxidant defence. Glutathione and ascorbic acid appear to be promising candidates for further investigation in this regard.

Ceftizoxima: evaluación in vitro / Ceftizoxime: in vitro evaluation

La ceftizoxima, una nueva aminotiazolil-syn metoxi-iminocefalosporina fue estudiada con 169 cepas de bacilos Gram negativos aisladas de pacientes internados y sus resultados comparados con los obtenidos con cefotaxima y ceftriaxona. Además fueron estudiadas 50 cepas de estafilococos con estas 3 cefalosporinas y con cefalotina. La CIM50 de ceftizoxima fue la siguiente: K. pneumoniae<032, E. cloaceae<.063, E. coli<.032, S. marcescens<.125, S. aureus y S. epidermidis<2. La CIM90 para las mismas especies fue: K. pneumoniae<.25, E. coli<.063, E. cloacae y S. marcescens <8., S. aureus<32, S epidermidis <16. Los valores obtenidos con cefotaxima y ceftriaxona fueron similares a los de ceftizoxima. Cefalotina fue netamente más activa sobre las cepas de estafilococos. Sus CIM50 y CIM90 para ambas especies fueron <.25 y <2. respectivamente