Indications of a new antibiotic in clinical practice: results of the tigecycline initial use registry

Tigecycline is the first of a new class of antibiotics named glycylcyclines and it was approved for the treatment of complicated intra-abdominal infections and complicated skin and skin structure infections. Notwithstanding this, tigecycline's pharmacological and microbiological profile which includes multidrug-resistant pathogens encourages physicians' use of the drug in other infections. We analyzed, during the first months after its launch, the tigecycline prescriptions for 113 patients in 12 institutions. Twenty-five patients (22 percent) received tigecycline for approved indications, and 88 (78 percent) for "off label" indications (56 percent with scientific support and 22 percent with limited or without any scientific support). The most frequent "off label" use was ventilator associated pneumonia (VAP) (63 patients). The etiology of infections was established in 105 patients (93 percent). MDR-Acinetobacter spp. was the microorganism most frequently isolated (50 percent of the cases). Overall, attending physicians reported clinical success in 86 of the 113 patients (76 percent). Our study shows that the "off label" use of tigecycline is frequent, especially in VAP. due to MDR-Acinetobacter spp., where the therapeutic options are limited (eg: colistin). Physicians must evaluate the benefits/risks of using this antibiotic for indications that lack rigorous scientific support.

Betalactámicos con inhibidores de betalactamasas: Amoxicilina-sulbactam / Betalactam antibiotics combined with bectalactamases inhibitors: Amoxicillin-sulbactam

La producción de betalactamasas constituye uno de los principales mecanismos de resistencia bacteriana a los antibióticos betalactámicos. La utilización de inhibidores de betalactamasas en combinación con antibióticos betalactámicos permite la inactivación de determinadas betalactamasas producidas por gérmenes Gram positivos, Gram negativos, anaerobios, y aun por micobacterias. Los inhibidores de betalactamasas representan una alternativa terapéutica mejorada respecto del resto de los betalactámicos al asegurar, en la mayoría de los casos, un mayor espectro antimicrobiano comparado con el de sus análogos. La actividad enzimática de las betalactamasas está dirigida específicamente a la hidrólisis del anillo betalactámico, con producción de un compuesto sin actividad antibacteriana. De acuerdo con su posición genómica dentro de los microorganismos, las betalactamasas pueden ser cromosómicas o plasmídicas. Actualmente existen tres inhibidores de betalactamasas localmente disponibles: ácido clavulánico, sulbactam y tazobactam. De ellos, sólo el sulbactam posee actividad antimicrobiana intrínseca sobre las proteínas ligadoras de penicilina. La experiencia clínica acumulada durante más de 20 años confirma que las combinaciones de betalactámicos-inhibidores de betalactamasas son efectivas en el tratamiento empírico inicial de infecciones respiratorias, intraabdominales, urinarias y ginecológicas, incluidas las de origen polimicrobiano. En el caso particular de amoxicilina-sulbactam, la evidencia citada indica que esta combinación es efectiva para el tratamiento de absceso periamigdalino, otitis media, sinusitis, neumonía extrahospitalaria, exacerbación aguda de enfermedad pulmonar obstructiva crónica (EPOC), infección del tracto urinario e infecciones ginecoobstétricas. Por su espectro y propiedades farmacológicas, la combinación amoxicilina-sulbactam constituye una excelente opción también para el tratamiento de infecciones de piel y partes blandas e infecciones intraabdominales.

Betalactamases production is one of the main bacterial resistance mechanisms to betalactam antibiotics. The use of bectalactamases inhibitors combined with betalactam antibiotics allows the inactivation of certain betalactamases produced by Gram positive, Gram negative and anaerobic organisms, and even by mycobacteria. Betalactamases inhibitors are an improved therapeutic alternative compared with the other betalactam since, in most cases, they cover a wider antimicrobial spectrum than their analogues. Betalactamases enzimatic activity is specifically directed to the betalactam ring hydrolisis, producing a compound without antibacterial activity. According to their genomic position within microorganisms, betalactamases can be either chromosomic or plasmidic. Currently there are three betalactamases inhibitors locally available: clavulanic acid, sulbactam and tazobactam. Of them, only sulbactam has an intrinsic antimicrobial activity against penicillin binding proteins. The clinical experience from over 20 years confirms that the combination of betalactam antibiotics is effective in the empirical initial treatment of respiratory, intraabdominal, urinary tract and gynecologic infections, including those of polymicrobial origin. In the specific case of amoxicillin-sulbactam, experiences have shown the effectiveness of the combination in the treatment of peritonsillar abscess, otitis media, sinusitis, community acquired pneumonia, acute exacerbation of chronic obstructive pulmonar disease (COPD), urinary tract infection and obstetric/ gynecologic infections. The spectrum and pharmacologic properties of this combination makes it also an excellent option for the treatment of skin/soft tissue and intraabdominal infections.

A multicenter comparative study of cefepime versus broad-spectrum antibacterial therapy in moderate and severe bacterial infections

The safety and efficacy of cefepime empiric monotherapy compared with standard broad-spectrum combination therapy for hospitalized adult patients with moderate to severe community-acquired bacterial infections were evaluated. In an open-label, multicenter study, 317 patients with an Acute Physiology and Chronic Health Evaluation (APACHE II) score ranging from >5 to =19 were enrolled with documented pneumonia (n=196), urinary tract infection (n=65), intra-abdominal infection (n=38), or sepsis (n=18). Patients were randomly assigned 1:1 to receive cefepime 1 to 2 g IV twice daily or three times a day or IV ampicillin, cephalothin, or ceftriaxone ± aminoglycoside therapy for 3 to 21 days. For both treatment groups, metronidazole, vancomycin, or macrolide therapy was added as deemed necessary. The primary efficacy variable was clinical response at the end of therapy. Two hundred ninety-six (93 percent) patients met evaluation criteria and were included in the efficacy analysis. Diagnoses included the following: 180 pneumonias (90 cefepime, 90 comparator), 62 urinary tract infections (29 cefepime, 33 comparator), 37 intra-abdominal infections (19 cefepime, 18 comparator), and 17 sepses (8 cefepime, 9 comparator). At the end of therapy, overall clinical success rates were 131/146 (90 percent) for patients treated with cefepime vs 125/150 (83 percent) for those treated with comparator (95 percent confidence interval [CI]: - 2.6 percent to 16.3 percent). The clinical success rate for patients with community-acquired pneumonia, the most frequent infection, was 86 percent for both treatment groups. Among the patients clinically evaluated, 162 pathogens were isolated and identified before therapy. The most commonly isolated pathogens were Escherichia coli (n=49), Streptococcus pneumoniae (n=29), Haemophilus influenzae (n=14), and Staphylococcus aureus (n=11). Bacteriologic eradication/presumed eradication was 97 percent for cefepime vs 94 percent for comparator-treated patients. Drug-related adverse events were reported in 16 percent of cefepime patients and 19 percent of comparator patients. In conclusion, cefepime had higher cure rates compared with broad-spectrum combination therapy as an initial empiric treatment for hospitalized patients with moderate to severe community-acquired infections, including urinary tract infections, intra-abdominal infections, and sepsis

Guias para el manejo de las infecciones osteoarticulares por Staphylococcus meticilino-resistente / [Guidelines for the management of bone and joint infections due to methicillin resistant staphylococci]

Bone and joint infections are a group of complicated diseases with high morbidity. Emerging resistant microorganisms and the use of prosthetic devices have increased the difficulty in the medical treatment of patients. The purpose of these guidelines is to offer information on the management of bone and joint infections (post-invasive septic arthritis, chronic osteomyelitis and infected arthroplasty) produced by methicillin resistant staphylococci. They are oriented to physicians dedicated to internal medicine, infectious diseases, trauma and orthopedist surgeons as well as to everybody interested in this issue. The guidelines mainly point to the rational use of diagnostic methods and describe the new treatment modalities. A group of experts analyzed the different strategies for diagnosing and treating bone and joint infections due to methicillin resistant staphylococci and attempted at setting a level of evidence level and the strength of each recommendation.

Teicoplanina en el tratamiento de las infecciones osteoarticulares por Staphylococcus meticilino-resistente. Experiencia en adultos / Teicoplanin in the treatment of bone and joint infections due to methicillin resistant staphylococci. Experience in adult patients

We retrospectively evaluated 89 episodes of bone and joint infections due to methicillin-resistant staphylococci: 56 chronic osteomyelitis (CO), 10 septic arthritis (SA) and 23 infections associated to arthroplasties (IAA). We analyzed the efficacy of Teicoplanin (T) in three times a week or daily administration schemes and adequate surgery (AS). Also, we determined cost savings derived from outpatient parenteral antibiotic therapy (OPAT). The overall efficacy of T in CO and both in cases with and without implants, was higher when antibiotic therapy was associated to AS (86 vs. 46, p = 0.001; 100 vs. 33, p = 0.0049 and 76 vs. 50, p = 0.09). All SA were cured. The overall efficacy of T was higher in IAA with implant removal vs. surgical debridement (100 vs. 54, p = 0.045). In all cases, T was similarly effective when administered three times a week vs. daily administration, when associated to AS. The savings derived from OPAT were 897 days/bed and USS 179,400. Adverse effects were few and light (8 episodes, 9). The results obtained are similar to those published in the literature and show that T administered daily or in a three times a week scheme and associated to AS, is effective and safe for the treatment of bone and joint infections. The savings derived from OPAT, mainly related to reduced hospitalization, are significant in these pathologies, which usually require long treatment periods