Haemophilus influenzae no tipificable: mecanismo de destrucción del biofilm / Non-typeable Haemophilus influenzae: mechanism of biofilm destruction

INTRODUCCIÓN: Haemophilus influenzae tiene como hábitat el aparato respiratorio humano. No existe vacuna contra la variante no tipificable (NTHi) de este, por lo que se ha mostrado una tendencia al incremento de casos en los últimos años. La patogenicidad de NTHi se debe a su habilidad para formar biofilms, por lo que se pretende analizar mecanismos de destrucción del biofilm formado por NTHi. METODOLOGÍA: Se realizó una revisión bibliográfica mediante consultas en las bases de datos, Hinari, MEDLINE y el motor de búsqueda PubMed. Se tomaron en consideración artículos originales, ensayos clínicos y artículos de revisión bibliográfica dando prioridad a aquellos publicados en los últimos 5 años. DESARROLLO: NTHi tiene la capacidad de formar biofilms por medio de proteínas del pili y elementos estabilizadores del ADN extracelular, entre los más importantes están: DNA BII, pili tipo IV, Nucleasa extracelular 2019 y adhesinas de alto peso molecular. El uso de chalconas, EDTA y ADN como quelante de cationes, antisueros contra DNBII y maquinaria luxS más anticuerpos contra Pili IV han demostrado que pueden ser útiles para la erradicación del biofilm. CONCLUSIÓN: Se proponen dos tratamientos novedosos que podrían contribuir en la eliminación del biofilm formado por NTHi, uno es el uso de EDTA y otro los anticuerpos dirigidos a proteínas esenciales en la formación y adhesión del biofilm. Es necesario profundizar en otros estudios con estas propuestas terapéuticas para determinar su uso en el área clínica en un futuro.

INTRODUCTION: Haemophilus influenzae has the human respiratory system as habitat. There's no vaccine against the non-typeable group (NTHi), as a consequence there has been an increase in the number of cases in the past few years. The pathogenesis of NTHi is caused by its ability to form biofilms, for this reason we pretend to analyze the destruction mechanisms of biofilms formed by NTHi. METHODOLOGY: A review was made using the databases Hinari, MEDLINE and PubMed. Original articles, clinical trials and reviews that had been published in the last five years were taken in count. RESULTS: NTHi has the capacity to form biofilms through pilus proteins and extracellular DNA stabilizers; among the most important we have: DNA BII, type IV pilus, 2019 extracellular nuclease and adhesins of high molecular weight. The use of chalcone, EDTA, DNA as cation chelant, antiserum against DNA BII and luxS plus antibodies against Pili IV has shown potential to eradicate biofilms. DISCUSSION: Two new treatments, that could contribute to the removal of biofilms formed by NTHi, are proposed: one of them is the use of EDTA and the other one is the use of antibodies against essential proteins that the bacteria uses in the formation and adhesion of biofilms. Never the less, it is necessary to deepen more in studies about these therapeutic alternatives to determine their use in the clinical area in the future.

Invasive Haemophilus influenzae disease in the vaccine era in Rio de Janeiro, Brazil

BACKGROUND Haemophilus influenzae (Hi) serotype b (Hib) conjugate vaccine was incorporated into the infant immunisation schedule in Brazil in 1999, where Hib was one of the major etiologic sources of community-acquired bacterial meningitis. OBJECTIVES The purpose of this study is to describe the molecular epidemiology of invasive Hi disease in Rio de Janeiro state, Brazil, before and after vaccine introduction. METHODS Surveillance data from 1986 to 2014 were analysed. Hi isolates recovered from cerebrospinal fluid (CSF) or blood from 1993 to 2014 were serotyped by slide agglutination, genotyped by multilocus sequence typing (MLST), and the capsule type evaluation, differentiation of serologically non-typeable isolates, and characterisation of the capsule (cap) locus was done by polymerase chain reaction. Antimicrobial susceptibility testing was performed using E-test. FINDINGS From 1986 to 1999 and from 2000 to 2014, 2580 and 197 (42% without serotype information) confirmed cases were reported, respectively. The case fatality rate was 17% and did not correlate with the strain. Hib and b- variant isolates belonged to ST-6, whereas serotype a isolates belonged to the ST-23 clonal complex. Serotype a appeared to emerge during the 2000s. Non-encapsulated isolates were non-clonal and distinct from the encapsulated isolates. Ampicillin-resistant isolates were either of serotype b or were non-encapsulated, and all of them were β-lactamase-positive but amoxicillin-clavulanic acid susceptible. MAIN CONCLUSIONS Although Hi meningitis became a relatively rare disease in Rio de Janeiro after the introduction of the Hib conjugate vaccine, the isolates recovered from patients have become more diverse. These results indicate the need to implement an enhanced surveillance system to continue monitoring the impact of the Hib conjugate vaccine.

Reduced Levofloxacin Susceptibility in Clinical Respiratory Isolates of Haemophilus Influenzae Is Not yet Associated with Mutations in the DNA Gyrase and Topoisomerase II Genes in Korea

Among 155 clinical respiratory isolates of Haemophilus influenzae in Korea, 6 (3.9%) isolates had reduced levofloxacin susceptibility (MICs > or = 0.5 microg/mL). These six isolates had no significant quinolone resistance-determining region (QRDR) mutations in gyrA, gyrB, parC, or parE. This phenomenon suggests that neither evolution nor spread of any significant QRDRs mutations in clinical isolates occurred in Korea. Therefore, continued surveillance is necessary to observe the evolution of antibiotic-resistance and take measures to avoid the spread of drug-resistant clones.

Reduced Levofloxacin Susceptibility in Clinical Respiratory Isolates of Haemophilus Influenzae Is Not yet Associated with Mutations in the DNA Gyrase and Topoisomerase II Genes in Korea

Among 155 clinical respiratory isolates of Haemophilus influenzae in Korea, 6 (3.9%) isolates had reduced levofloxacin susceptibility (MICs > or = 0.5 microg/mL). These six isolates had no significant quinolone resistance-determining region (QRDR) mutations in gyrA, gyrB, parC, or parE. This phenomenon suggests that neither evolution nor spread of any significant QRDRs mutations in clinical isolates occurred in Korea. Therefore, continued surveillance is necessary to observe the evolution of antibiotic-resistance and take measures to avoid the spread of drug-resistant clones.

Asymptomatic colonization of upper respiratory tract by potential bacterial pathogens.

Objective. To screen for asymptomatic respiratory carriage of S. pneumoniae, H. influenzae and Group A Streptococcus (GAS) in children attending JIPMER, correlate carriage rate with different socio-demographic factors and to detect antimicrobial resistance among the isolates. Methods. Throat swabs were collected from both in patients and out patients (≤12 yr of age) and processed. Bacteria were identified by standard techniques. Susceptibility to commonly used antimicrobial agents was determined by Kirby Bauer disc diffusion technique. Results. Overall carriage rate of respiratory pathogens was 30% with S. pneumoniae, H. influenzae and GAS accounting for 22%, 5% and 4.5% respectively. Three patients had >1 organism. Antibiotic resistance was highest in S. pneumoniae with 66.7% of strains resistant to penicillin. MDR strains were also encountered. Erythromycin resistance was observed in both H. influenzae (28.4%) and GAS (22%).No statistically significant association was found between the carriage rate of these organisms and different socio-demographic factors. Conclusions. S. pneumoniae carriage rate was comparatively higher in the community and its antimicrobial resistance is an issue to address.

Etiology and antimicrobial susceptibility pattern of otitis media in children at Princess Rhamah Hospital in Jordan

Otitis media is one of the most common infections in children. Recently it was noticed that there is a marked increase in relapse of otitis media in children. Therefore, this study conducted to investigate microorganisms causing otitis media in children and to assess their sensitivity to various groups of antimicrobial. A retrospective study was conducted on positive cultures taken from 173 children aged below 15 years, who attended as outpatient or inpatient at Princess Rahmah Hospital between January and December/ 2008. The obtained data were analyzed and the results were tabulated. A total of 173 isolates were recovered from cultures obtained from children patients. The male and female isolates ratio was [1.24:1.0]. The most frequent pathogen found was S. aureus [68.2%], followed by Streptococcus spp. [12.1%], H. influenzae [9.3%], Psudomonas spp [6.9%] and Klebsiella spp. [3.9%]. The susceptibility rate of S. aureus was recorded the highest [95.9%] for vancomycin, and the lowest susceptibility rate [31.8%] was recorded for oxacillin. S. aureus was the main isolate of otitis media in children, which almost all isolates were susceptible to cefotaxime, ciprofloxacin and vancomycin. Overall oxacillin resistance was near 67%. This information should be considered when empirical therapy is recommended or prescribed for children with otitis media

Antimicrobial resistance of bacterial agents of the upper respiratory tract of school children in Buea, Cameroon.

The study was aimed at determining bacterial agents of the upper respiratory tract and the susceptibility patterns of isolates to antibiotics. In total, 200 throat swabs were obtained from students attending different boarding schools within the Buea Municipality and screened to obtain the prevalence of respiratory pathogens and to understand the antibiotic susceptibility patterns of isolates using standard microbiological procedure and the disc-diffusion test. Of the 200 samples screened, 112 (56%) had positive cultures with the dominant bacterial pathogens being Haemophilus influenzae (20%), followed by Streptococcus pneumoniae (15%), Klebsiella pneumoniae (11%), and Staphylococcus aureus (10%). Although 56% of the isolates were recovered from females compared to 44% from males, the difference was not statistically significant (p>0.05). Sixty-seven percent of the pathogens were isolated from the age-group of 10-13 years, 19.6% from the age-group of 14-17 years, and 12.5% from the age-group of 18-21 years. Antibiotic susceptibility testing revealed that gentamicin (92%) and cefuroxime (88.4%) were the most effective antibiotics against the isolates. Generally, susceptibility ranged from 0% to 92% depending on the antibiotic and the species of microorganism. Penicillin had the highest (100%) resistance to all the isolates. The findings revealed that students living in boarding schools in the Buea Municipality were at risk of acquiring upper respiratory tract infections from their peers since the upper respiratory tract of more than 50% of the students was colonized with respiratory pathogens. Although multidrug-resistant strains of organisms were identified, gentamicin and cefuroxime are recommended as the first-line antibiotics of choice against the pathogens. There is, therefore, a need for surveillance of nasopharyngeal carriage of resistant strains of these organisms, especially H. influenzae in unhealthy school children since the vaccine is yet to be introduced in Cameroon. The findings have clinical and epidemiological significance.

Five-year study of antimicrobial susceptibility and beta-lactamase production in Haemophilus influenzae.

We evaluated 582 Haemophilus influenzae isolates from patients between January 2000 and December 2004. Overall, 433 isolates were obtained from sputum and bronchial washings, 124 isolates were from pus, 19 isolates were from blood and 6 isolates form cerebrospinal fluid. H. influenzae was sensitive to amoxicillin/clavulanate, ampicillin/sulbactam, gentamicin, cefuroxime, ceftriaxone, cefotaxime, ciprofloxacin, ofloxacin, imipenem, meropenem (range 97-100%), chloramphenicol (75%), ampicillin/amoxicillin (52%), but resistant to trimethoprim-sulphamethoxazole. As for beta-lactamase production, 48.4% of the isolates tested were positive.

A population-based study of hospital admission incidence rate and bacterial aetiology of acute lower respiratory infections in children aged less than five years in Bangladesh.

The research was carried out to study the rate of population-based hospital admissions due to acute lower respiratory infections (ALRIs) and bacterial aetiology of ALRIs in children aged less than five years in Bangladesh. A cohort of children aged less than five years in a rural surveillance population in Matlab, Bangladesh, was studied for two years. Cases were children admitted to the Matlab Hospital of ICDDR,B with a diagnosis of severe ALRIs. Bacterial aetiology was determined by blood culture. Antimicrobial resistance patterns of Haemophilus influenzae type b (Hib) and Streptococcus pneumoniae (Spn) isolates were determined using the disc-diffusion method. In total, 18,983 children aged less than five years contributed to 24,902 child-years of observation (CYO). The incidence of ALRI-related hospital admissions was 50.2 per 1,000 CYO. The incidences of ALRI were 67% higher in males than in females and were higher in children aged less than two years than in older children. About 34% of the cases received antibiotics prior to hospitalization. Of 840 blood samples cultured, 39.4% grew a bacterial isolate; 11.3% were potential respiratory pathogens, and the rest were considered contaminants. The predominant isolates were Staphylococcus aureus (4.5%). Hib (0.4%) and Spn (0.8%) were rarely isolated; however, resistance of both these pathogens to trimethoprim-sulphamethoxazole was common. The rate of ALRI-related hospitalizations was high. The high rate of contamination, coupled with high background antibiotic use, might have contributed to an underestimation of the burden of Hib and Spn. Future studies should use more sensitive methods and more systematically look for resistance patterns of other pathogens in addition to Hib and Spn.

Beta-lactamase production Haemophilus spp. and resistance to ampicillin in a general hospital in Porto Alegre city, RS, Brazil (2001-2005)

In a four-year period (July/2001-June/2005), 410 Haemophilus spp. isolates were studied. Those were isolated from sputum at Hospital Nossa Senhora da Conceição (NSC) in Porto Alegre city (RS). beta-lactamase enzyme was detected in 113 (27.6 percent) of isolates through chromogenic cephalosporin method. Fifty-eight (51.3 percent) of them showed sensibility to ampicillin through disc-diffusion method using Haemophilus Test Medium (HTM) by NCCLS criteria. In 297 (72.4 percent) isolates beta-lactamase was not detected by chromogenic cephalosporin method. Five (1.7 percent) of them were resistant and 1 (0.3 percent) intermediate to ampicillin using disc-diffusion method. The authors emphasized the importance of Haemophilus spp. resistance to ampicillin research in clinical laboratories routine and the use of more than one method for this analysis was proposed, due to different resistance mechanisms in Haemophilus spp.

In vitro Activities of Oral Cephem and Telithromycin Against Clinical Isolates of Major Respiratory Pathogens in Japan

The in vitro antibacterial activities of oral cephem antibiotics and ketolide telithromycin against major respiratory pathogens possessing beta-lactam-resistant mutations (within the pbp gene) and/or macrolide-resistant genes (erm and mef) were examined in clinical isolates collected at 66 institutes in all over the Japan between 2002 and 2003. Telithromycin showed the strongest antibacterial activity against methicillinsusceptible Staphylococcus aureus strains with and without macrolide-resistant genes, such as ermA or ermC gene. All the cephem antibiotics showed potent antibacterial activity against Streptococcus pyogenes, with minimum inhibitory concentrations (MICs) of 0.015 mg/L or lower. Cefdinir had a much higher MIC90 against genotypic penicillin-resistant Streptococcus pneumoniae (gPRSP) than cefditoren and cefcapene (8 mg/L cefdinir vs. 1 mg/L cefditoren and cefcapene). The majority of gPRSP harbored either ermB or mefA, and the antibacterial activity of telithromycin against these strains was decreased however some susceptibility was still sustained. Cefditoren exerted the strongest antibacterial activity against beta-lactamase-negative ampicillin-resistant Haemophilus influenzae, with an MIC90 of 0.5 mg/L. These results underline the importance of checking the susceptibility and selecting an appropriate antibiotic against target pathogens.

Outpatient antibiotic therapy as a predisposing factor for bacterial resistance: a rational approach to airway infections

OBJETIVOS: Apresentar as recomendações baseadas em evidência para uso de antibióticos no tratamento das infecções respiratórias agudas (IRA) mais freqüentes e as informações disponíveis sobre a importância desse tipo de conduta. FONTES DOS DADOS: Bases de dados MEDLINE, LILACS, publicações técnicas de organizações internacionais, diretrizes nacionais e internacionais. Foram utilizados os unitermos acute respiratory infection, otitis, sinusitis, tonsillitis, pneumonia, antibiotic, guidelines, bacterial resistance. Artigos citados pelos artigos incluídos foram analisados quanto à apresentação de informação de interesse. SíNTESE DOS DADOS: A resistência bacteriana tem crescido, sendo atualmente reconhecida como problema mundial de saúde pública. As IRA são a causa mais freqüente para uso de antibiótico na comunidade; grande parte desses casos, tanto nas vias aéreas superiores (otite, sinusite, faringoamidalite) como nas inferiores (pneumonia), são decorrente de infecção viral. As recomendações para racionalizar o uso de antibióticos nos pacientes com IRA têm como objetivo comum minimizar o uso desnecessário de antibióticos, visto que a "pressão antibiótica" é um dos fatores desencadeantes da resistência bacteriana. CONCLUSÕES: É de grande importância a distinção, entre os pacientes com IRA, daqueles que podem se beneficiar do uso de antibióticos. O uso das recomendações para a prescrição de antibióticos é uma estratégia para minimizar a freqüência de resistência bacteriana.

OBJECTIVES: To present evidence-based recommendations for the use of antibiotics for the treatment of the most common acute respiratory infections (ARI) and the available information on the importance of this type of management. SOURCES: MEDLINE and LILACS databases, technical publications by international organizations, national and international directives. The search terms acute respiratory infection, otitis, sinusitis, tonsillitis, pneumonia, antibiotic, guidelines and bacterial resistance were used. Articles cited by the articles selected were analyzed for information of interest. SUMMARY OF THE FINDINGS: Bacterial resistance has grown, to the extent that today it is recognized as a global public health problem. ARI are the most common cause of antibiotic usage within the community; yet a large proportion of these cases, compromising the upper (otitis, sinusitis, tonsillitis) or the lower airways (pneumonia), are the result of viral infections. Recommendations to rationalize the use of antibiotics in patients with ARI have the common objective of minimizing unnecessary antibiotic use, since "antibiotic pressure" is one of the factors triggering bacterial resistance. CONCLUSIONS: It is of great importance to differentiate among ARI patients those who will benefit from the use of antibiotics. The establishment of recommendations for the prescription of antibiotics is one strategy for minimizing the frequency of bacterial resistance.

In vitro activity of fluoroquinolones against common respiratory pathogens / La actividad in vitro de las fluorquinolonas contra los patógenos respiratorios

The treatment of respiratory infections is often empiric, necessitating the use of agents with a broad range of antimicrobial activity. The fluoroquinolones, having activity against common respiratory pathogens, fit this description. New fluoroquinolones have been developed in an attempt to improve the in vitro activity against a wide variety of respiratory tract pathogens. The objective of the study is to compare in vitro activity of newest fluoroquinolones, gatifloxacin and moxifloxacin, with levofloxacin and ciprofloxacin using three major respiratory pathogens, Streptococcus pneumoniae, Haemophilus influenzae and Moraxella catarrhalis. Minimum inhibitory concentrations (MICs) of four fluoroquinolones were tested against 93 S pneumoniae, 62 H influenzae and 60 M catarrhalis, ie 215 isolates by the E-test method. National Committee for Clinical Laboratory Standards (NCCLS)-approved interpretive criteria were used throughout. All isolates were susceptible to the tested fluoro-quinolones. Ninety per cent of S pneumoniae strains were inhibited by ciprofloxacin at concentrations of 2 mg/L. The gatifloxacin and moxifloxacin MICs were lower than the ciprofloxacin and levofloxacin MICs against S pneumoniae. In contrast to S pneumoniae, in vitro activities of gatifloxacin and moxifloxacin offered no apparent advantages over ciprofloxacin and levofloxacin for H influenzae and M catarrhalis.

La terapia de las infecciones respiratorias es a menudo empírica, y exige por ende el uso de agentes con un amplio espectro de actividad antimicrobiana. Por su actividad contra los patógenos respiratorios comunes, las fluorquinolonas se ajustan a esta descripción. Nuevas fluorquinolonas han sido desarrolladas, en un intento por mejorar la actividad in vitro contra una variedad de patógenos de las vías respiratorias. El objetivo de este estudio es comparar la actividad in vitro de las fluorquinolonas más recientes – la gatifloxacina y la moxifloxacina – con la levofloxacina y la ciprofloxacina, usando tres de los más importantes patógenos respiratorios: Streptococcus pneumoniae, Haemophilus influenzae y Moraxella catarrhalis. Las concentraciones inhibitorias mínimas (CIMs) de las cuatro fluorquinolonas fueron sometidas a prueba contra 93 S pneumoniae, 62 H influenzae y 60 M catarrhalis, para un total de 215 aislados mediante el método de E-test. En todos los casos se aplicaron criterios interpretativos aprobados por el Comité Nacional para Normas del Laboratorio Clínico (NCCLS). Todos los aislados resultaron sensibles a las fluorquinolonas ensayadas. El noventa por ciento de las cepas de S pneumoniae fueron inhibidas por la ciprofloxacina a concentrationes of 2 mg/L. Las CIMs de la gatifloxacina y la moxifloxacina fueron más bajas que las CIMs de la ciprofloxacina y la levofloxacina contra S pneumoniae. En contraste con S pneumoniae, la actividad in vitro de la gatifloxacina y la moxifloxacina no ofrecieron ventajas aparentes por encima de la ciprofloxacina y la levofloxacina frente a H influenzae y M catarrhalis.

Experience of cefotaxime as first line antibiotic in acute bacterial meningitis

To find out efficacy safety and tolerability of cefotaxime sodium [Cefotax] as first line antibiotic. An Observational analytic study. Child Medicare Center Larkana for the period of 18 months from July 2003 to December 2004. fifty six patients having cerebrospinal fluid favoring acute bacterial meningitis between 2 months to 12 years of age with set inclusion criteria were included in the study. CSF aspiration was per formed under strict aseptic technique and sent .for routine examination and culture in every case to detect the organisms and see the pattern of sensitivity. CSF was repeated in all cases to confirm the clearance. The data were recorded and than statistically analyzed. Total male 37/56 and female 19/56 with male to female ratio were 2:1. Culture-was positive in 28.57% patients [16/56], while 71.42% [40/56] cases revealed no organism. The most cases were below 6 years of age. The maximum sensitivity seen with cefotaxime [100%] and higher proportion of resistant to gentamycin [75%]. The Predominant Organisms were below 6 year of age were S. Pneumoniae and H. Influenzae. Neurological morbility was more in patients < 6 years of age [8.92%] while above this age were [1.78%]. The case fatality was [1/56] [2%] and with S. Pneumoniae organism. Culture was positive in 28.57% patients. The most common organism were S.pnenmoniae. H. influenzae and Meningococcus. Mostly the organisms are sensitive to cefotaxime and ceftriaxone, as first line antibiotic in acute bacterial meningitis, cefotaxime is safe, effective and reliable

Respiratory tract infection caused by bacteria (non-Mycobacterium) and their antibiogram in HIV-positive patients.

Abstract. This study was undertaken from 1995-2000 to investigate the cause of respiratory tract infection among 481 patients with human immunodeficiency virus (HIV) at Siriraj Hospital, Bangkok, Thailand. The positive rate of bacterial pathogens was 38.46%. Pseudomonas aeruginosa appeared to be the most common pathogen (32.97%), followed by Staphylococcus aureus (18.92%), Klebsiella pneumoniae (10.81 %), Haemophilus influenzae (7.57%), and Acinetobacter baumannii (5.95%). P. aeruginosa was sensitive to netilmycin, amikacin, imipenem, meropenem, cefoperazone/sulbactam, piperacillin/tazobactam, and gentamicin (67-84%). S. aureus was sensitive to vancomycin and teicoplanin (100%).

Comparison of disc diffusion & E test methods with agar dilution for antimicrobial susceptibility testing of Haemophilus influenzae.

BACKGROUND & OBJECTIVES: Reliable methods of detection of antimicrobial resistance are of paramount importance in the treatment and management of infections caused by Haemophilus influenzae. The objective of the present study was to compare and evaluate the performance of disc diffusion and E test (Epsilometer test) with agar dilution method for antimicrobial susceptibility testing of H. influenzae. METHODS: A total of 46 isolates of H. influenzae from various invasive sites were included as test strains. Antimicrobial susceptibility testing was performed by Kirby-Bauer disc diffusion method for ampicillin, chloramphenicol, trimethoprim-sulphamethoxazole (TMP-SMZ) and cefotaxime. Minimum Inhibitory Concentration (MIC) determination was performed by E test and agar dilution for the same set of antimicrobials. All tests were performed on Haemophilus test medium (HTM). RESULTS: Disc diffusion showed a very major (2%) and minor (4%) interpretative error with TMP-SMZ and minor interpretative errors to ampicillin (13%) and chloramphenicol (24%) when compared to agar dilution method. E test produced only minor interpretative errors to chloramphenicol (7%) and TMP-SMZ (2%) and no interpretative errors with ampicillin and cefotaxime as against agar dilution. E test showed good agreement with agar dilution for each of the antimicrobial tested. INTERPRETATION & CONCLUSION: Disc diffusion test may be used as a preliminary screen for susceptibility testing of H. influenzae. E test is simple, easy to perform and a reliable method for determination of resistance in H. influenzae. However its cost and limited availability in India may limit its use. The reference agar dilution method can be used reliably in routine susceptibility testing of H. influenzae.

Antibacterial resistance of community-acquired respiratory tract pathogens recovered from patients in Latin America: results from the PROTEKT surveillance study (1999-2000)

PROTEKT (Prospective Resistant Organism Tracking and Epidemiology for the Ketolide Telithromycin) is a global surveillance study established in 1999 to monitor antibacterial resistance of respiratory tract organisms. Thirteen centers from Argentina, Brazil and Mexico participat ed during 1999-2000; they collected 1,806 isolates (Streptococcus pneumoniae 518, Haemophilus influenzae 520, Moraxella catarrhalis 140, Staphylococcus aureus 351, S. pyogenes 277). Overall, 218 (42.1 percent) of the S. pneumoniae isolates had reduced susceptibility to penicillin, 79 (15.3 percent) were penicillin-resistant and 79 (15.3 percent) were erythromycin-resistant. Mexico had the highest prevalence of penicillin (76.5 percent) and erythromycin (31.2 percent) resistance. Of 77 erythromycin-resistant S. pneumoniae tested for resistance genotype, 43 possessed mef(A), 33 possessed erm(B) and 1 possessed both erm(B) and mef(A) mechanism. All S. pneumoniae isolates were fully susceptible to telithromycin, linezolid, teicoplanin and vancomycin. Among H. influenzae isolates, 88 (16.9 percent) produced b-lactamase, ranging from 11 percent (Brazil) to 24.5 percent (Mexico). Among M. catarrhalis isolates, 138 (98.6 percent) produced b-lactamase. Twenty-four (8.7 percent) of the S. pyogenes isolates were erythromycin-resistant; resistance being attributable to mefA (n=18), ermTR (n=5) and ermB (n=1). All H. influenzae, M. catarrhalis and S. pyogenes were fully susceptible to telithromycin. Methicillin resistance was found in 26.5 percent of the S. aureus isolates (Argentina 15 percent; Mexico 20 percent; Brazil 31.3 percent). Telithromycin was effective against 97.7 percent of methicillin-susceptible isolates. PROTEKT confirms that antibacterial resistance is an emerging problem in Latin America. The previously reported high levels of pneumococcal resistance to the b-lactam and macrolides were exceeded. New agents that do not induce resistance or that exert low selective pressure, e.g. telithromycin, are essential to safeguard future antibacterial efficacy

An open label, multicenter, non-comparative study of the efficacy and safety of oral gatifloxacin in the treatment of community-acquired pneumonia: a Brazilian study in five centers

We made an open label, multicenter, non-comparative study to assess the efficacy and safety of oral gatifloxacin, 400mg PO given once-daily during 7 to 14 days for the treatment of adult outpatients with community-acquired pneumonia at five Brazilian medical facilities. Among the 86 subjects available for clinical evaluation, 84 (98 percent) were cured. The bacteriological eradication and presumed eradication rate was 98 percent (52/53) among the 44 (51 percent) patients who were bacteriologically evaluated. Drug-related adverse events were reported by 27 percent of the patients, diarrhea being the most frequent, occurring in 12 percent of patients. Adverse events were considered mild (89 percent) or moderate (11 percent). We conclude that a 7-14 day course of gatifloxacin, 400mg PO given once daily is safe and effective for the treatment of community-acquired pneumonia. The drug had a favorable safety profile and a good clinical and bacteriological efficacy

Nasopharyngeal carriage of Haemophilus influenzae.

OBJECTIVE: Nasopharyngeal colonization of Haemophilus influenzae (H. influenzae) in young children may be important in developing countries. METHOD: In this study, we screened school going children for carriage of H. influenzae. A total of 44 H. influenzae isolates out of a collection of 162 were characterized for biotypes, capsular serotypes and antibiotic resistance. RESULTS: A significant proportion of H. influenzae (25/44) isolates were serotype b. High antibiotic resistance was observed against commonly administered antibiotics like ampicillin (79%), chloramphenicol (20%), trimethoprim sulfamethoxazole (84%) and erythromycin (95%). Comparison of antibiotic resistance profile of nasopharyngeal isolates was observed to be correlated with those of H. influenzae from disease. CONCLUSION: Multidrug resistant nasopharyngeal H. influenzae in young healthy children may act as reservoir. Monitoring of antibiotic resistance among nasopharyngeal H. influenzae as a surrogate for invasive H. influenzae seems an attractive option.