Rev Esp Quimioter 2008;21(1):37-44

Improvement of bactericide activity in hospital treatment of gram positive infections

 

L. Aguilar ,  J. Barberán ,  J. Prieto ,  M. J. Giménez 

  

Vancomycin is currently the standard treatment of gram-positive bacteria inducted nosocomial infections. However its bactericidal activity may be affected by different factors related to its antibacterial activity, pharmacokinetic properties or the infecting bacteria. Based on these facts, this article reviews the clinical importance that bactericidal activity has against susceptible bacteria and the compromise of this activity due to inadequate pharmacodynamic parameter values. From the bacterial target perspective, the clinical importance of the compromised bactericidal activity due to the decreased susceptibility, tolerance, heteroresistance and resistance is reviewed. In addition the characteristics of an antimicrobial targeted for gram positive nosocomial infections as well as the degree of adhesion to them of the bactericidal antibiotic daptomycin are described.

  

Key words:Vancomycin. Daptomycin. Bactericidal activity. Heterorresistance. Tolerance. 

  

Rev Esp Quimioter 2008;21(1):37-44 [pdf]  

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Rev Esp Quimioter 2008;21(1):32-36

Analysis of decrease in sensitivity in influenza A (H5N1) avian and human strains to neuraminidase inhibitors

 

J. Reina 

The options for efficient control of avian influenza A (H5N1) viruses include specific vaccination and antiviral prophylaxis and treatment. However, because H5N1 viruses undergo continuous antigen mutations, the production of a matched vaccine strain is currently not possible. Thus, during the early pandemic period, specific control measures would rely solely on antiviral drugs. Now only neuraminidase inhibitors (NIs) (zanamivir and oseltamivir) are considered for prophylaxis and therapy in patients with H5N1 infection. The sensitivies of H5N1 strains to the NIs fell into 3 groups. The clade I viruses isolated before 2004 were as sensitive to NIs than reference strains (first group). But the clade I viruses isolated from 2004 were 6 to 7-fold less sensitivity to NIs (second group). The clade II strains isolated from 2005 to 2007 demonstrated a 15 to 30 fold decrease in sensitivity to oseltamivir compared with clade I viruses (third group). The specific decrease in sensitivity to oseltamivir of both Cambodian and Indonesian clade 2 influenza H5N1 isolates is disturbing, especially because they maintain their pathogenicity and transmissibility in birds and are clearly pathogenic in humans. No altered sensitivity to zanamivir has been detected. Zanamivir may also play an important role in pandemic stockpiles. Because the clade 2 virus is now spread through parts of Europe and Africa, continued global collaboration and phenotypic testing of NIs sensitivity are critical for a future pandemic. 

 

 

Key words:Avian influenza. H5N1. Neuraminidase inhibitors. Antiviral resistance.

Rev Esp Quimioter 2008;21(1):32-36 [pdf]

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Rev Esp Quimioter 2008;21(1):26-31

Antimicrobial selection criteria evaluation by family doctors and general practitioners

M. A. Ripoll ,  A. Orero ,  D. Vicente ,  A. Navarro ,  J. Gónzález ,  J. Prieto 

 

Objective. This study has aimed to know the criteria used by the Spanish medical practitioners/family doctors (MP/FD) when choosing an antimicrobial agent in their daily practice and to compare it with that existing one decade ago.

 

Material and methods. This is an observational, cross-sectional study performed with a structured personal interview to 450 MP/FDs randomly chosen with representativeness on the national level. The field work was made by specialized personnel in the last quarter of the year 2006. A 95.5% confidence interval margin was proposed, with a sample error = 4.7%, for maximum dispersion response (p=q=50).

 

Results. The parameter considered most when choosing an antibiotic treatment (spontaneous response) is clinical efficacy (two out of every three doctors). Clinical efficacy is following by the dosage regime and tolerability/safety, which was the principal parameter expressed ten years ago. Following these are antibacterial spectrum, administration route, price and bacterial resistances. However, they considered that the latter significantly influence clinical efficacy and when they are not relativized with other parameters, the doctors state that they take them into account «much/a lot». It seems that the opinion of the patient is usually considered and that the protocol, scientific information and expert’s opinions are the principal sources of information considered when prescribing an antimicrobial agent. Amoxicillin/clavulanate is the antibiotic drug of choice in all upper and lower respiratory tract infections. There is overestimation of the bacterial etiology in throat infections and acute bronchitis and S. pyogenes to betalactamic antibiotics. It is concluded that knowledge of the Spanish MP/DF regarding antimicrobial therapy has improved in recent years and that clinical efficacy, related with bacterial eradication and not only with clinical remission, is the factor that should be considered when choosing an antibiotic.

 

Key words:Antimicrobial therapy. Utilization of antibiotics. Antibiotic selection criteria. Antibiotics. Primary health care.

Rev Esp Quimioter 2008;21(1):26-31 [pdf]  

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Rev Esp Quimioter 2008;21(1):22-25

Situation of Mycobacterium tuberculosis drug resistances in Spain

 

M. S. Jiménez ,  M. Casal ,   (GEM) 

  

Introduction. The Mycobacteriology Spanish Working Group (MSWG) has conducted an epidemiological, descriptive and retrospective study to try to know the level of first line drug resistances in Mycobacterium tuberculosis strains in Spain.

 

Material and methods. Data were obtained from a total of 1083 strains isolated between October and November 2006 in 120 microbiology laboratories from 16 autonomous communities and Melilla.

  

Results. A primary resistance rate of 8.3% and 4.9% was obtained for isoniazid (INH). The probability of suffering resistant tuberculosis was major in the immigrant population with a resistance rate of 12%. Repeating these surveillance studies in later years is recommended.

Key words: Tuberculosis. Resistance. Antituberculous agents.

Rev Esp Quimioter 2008;21(1):22-25 [pdf]  

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Rev Esp Quimioter 2008;21(1):14-21

Efficacy of cefditoren in the treatment of upper respiratory tract infections: a pooled analysis of six clinical trials

J. J. Granizo ,  M. J. Giménez ,  J. Barberán ,  P. Coronel ,  M. Gimeno ,  L. Aguilar  

Objective. A pooled analysis of all upper respiratory tract infection studies performed with cefditoren (CDN) was performed.  

Methods. Studies were prospective, comparative, multicentre and randomised. Comparators were penicillin V (pharyngitis) and cefuroxime or amoxicillin/clavulanate (sinusitis). A total of 1,322 patients were randomized, 1,241 included in intention-to-treat (ITT) and 1,010 in per-protocol populations (PP) in pharyngotonsillitis studies, and 1,819 randomized, 1,726 included in ITT and 1,589 in PP in acute sinusitis studies. 

Results. No significant differences in pharyngitis clinical response were found (success rates: 89.4 % to 95.3 %). S. pyogenes eradication was higher with cefditoren at end of therapy (EOT) (90.4% vs. 82.7%; p=0.002) and follow-up (84.7% vs. 76.7%; p=0.008), although no statistically significant (p<0.001). In both groups, clinical failures were significantly higher (p<0.001) in patients showing S. pyogenes persistence than in those showing eradication (≥98.5% vs. 51.4 %). No differences in sinusitis clinical response were found between CDN and comparators both at EOT (80.2% vs. 84.8%) and at end of follow-up (71.2% vs. 77.4%).  

Conclusion. Cefditoren had similar point estimates of clinical efficacy to comparators in pharyngotonsillitis and sinusitis, and a tendency to higher S. pyogenes eradication in pharyngotonsillitis.   

Key words:Cefditoren. S. pyogenes. Clinical trial. Pooled analysis. Sinusitis. Pharyngotonsillitis.   

 

Rev Esp Quimioter 2008;21(1):14-21 [pdf] 

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Rev Esp Quimioter 2008;21(1):4-13

Behavior of the Primary Care physicians in the treatment of community infections

 A. Orero ,  A. Navarro ,  S. López ,  M. A. Ripoll ,  J. González ,  J. Prieto   

This study aimed to evaluate the behavior of the physicians who attend to patients with community infections who are responsible for most of the antibiotic prescriptions made in the community setting. Furthermore, the evolution over the last 10 years in regards to the treatment habits of the most frequent infections in Primary Health Care (PHC) was studied and prescription behaviors were analyzed in relationship to the acquaintance and attitude of the participating physicians. A data collection sheet from 1,411 prescriptions made by 855 physicians from different specialties was used to conduct the study. This represents a statistically significant sample nationwide both from the point of view of the physicians involved in the treatment of infectious diseases in PHC as well as regarding to the prescriptions they have written. The study reveals the amplitude of respiratory and pararespiratory disease with oral antimicrobial agents, particularly beta-lactamics, and the significant advance in the last 10 years in the use of amoxicillin and clavulanic acid as treatment of choice. Treatment duration was somewhat longer while the number of containers prescribed was less than in the previous study. This would be related to the use of more spaced doses of the antimicrobial agents. Furthermore, the study reveals some discrepancies between attitudes and events of the physicians in the approach to certain diagnoses. 

Key words:Behavior. Primary care physicians. Prescription. Antimicrobials agents.  

Rev Esp Quimioter 2008;21(1):4-13 [pdf] 

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