Beta-lactamase-producing Bacteria Research Articles

Efficacy of an inulin-based treatment on intestinal colonization by multidrug-resistant E. coli: insight into the mechanism of action

ABSTRACT Inulin, an increasingly studied dietary fiber, alters intestinal microbiota. The aim of this study was to assess whether inulin decreases intestinal colonization by multidrug resistant E. coli and to investigate its potential mechanisms of action. Mice with amoxicillin-induced intestinal dysbiosis mice were inoculated with extended spectrum beta-lactamase producing E. coli (ESBL-E. coli). The combination of inulin and pantoprazole (IP) significantly reduced ESBL-E. coli fecal titers, whereas pantoprazole alone did not and inulin had a delayed and limited effect. Fecal microbiome was assessed using shotgun metagenomic sequencing and qPCR. The efficacy of IP was predicted by increased abundance of 74 taxa, including two species of Adlercreutzia. Preventive treatments with A. caecimuris or A. muris also reduced ESBL-E. coli fecal titers. Fecal microbiota of mice effectively treated by IP was enriched in genes involved in inulin catabolism, production of propionate and expression of beta-lactamases. They also had increased beta-lactamase activity and decreased amoxicillin concentration. These results suggest that IP act through production of propionate and degradation of amoxicillin by the microbiota. The combination of pantoprazole and inulin is a potential treatment of intestinal colonization by multidrug-resistant E. coli. The ability of prebiotics to promote propionate and/or beta-lactamase producing bacteria may be used as a screening tool to identify potential treatments of intestinal colonization by multidrug resistant Enterobacterales.

Risk Factors for the Development of Urinary Tract Infection During Pregnancy Caused by Extended-Spectrum Beta-Lactamase Producing Gram-Negative Bacteria

Risk Factors for the Development of Urinary Tract Infection During Pregnancy Caused by Extended-Spectrum Beta-Lactamase Producing Gram-Negative Bacteria

Occurrence of Extended Spectrum Beta Lactamase (ESBL) Producing Gram-Negative Bacteria in Wastewaters from Selected Hospitals in Ibadan, Oyo State, Nigeria

Occurrence of Extended Spectrum Beta Lactamase (ESBL) Producing Gram-Negative Bacteria in Wastewaters from Selected Hospitals in Ibadan, Oyo State, Nigeria

Rekurentni akutni tonzilitis - terapijski izazovi

Introduction: Acute tonsillopharyngitis is one of the most common infections of the upper respiratory tract, and in a number of patients a relapse of the infection may occur shortly after the termination of antibiotic treatment. It is more likely that recurrent acute tonsillopharyngitis (RATP) is primarily a result of therapeutic failure in pathogen eradication. Penicillin failure in the treatment of bacterial tonsillopharyngitis. The explanation for the penicillin failure in the treatment of bacterial tonsillopharyngitis should be sought in its inability to eradicate intracellular beta-hemolytic streptococci group A (GABHS), as well as its inability to achieve therapeutic concentration in the tonsillar surface fluid. Furthermore, betalactamase-producing bacteria (BLPB) act protectively against GABHS by inactivating penicillin. The synergistic effect with GABHS is frequently achieved with Moraxella catarrhalis, which in addition to the production of this enzyme, also enhances the adherence of GABHS to human epithelial cells. Normal bacterial flora with its various mechanisms influences on the colonization of pathogens and subsequent infection. It behaves competitively for nutrients and suppresses the growth of other strains with its products. This behavior is called bacterial interference and the best-known interfering bacterium is Alpha-hemolytic streptococcus. The presence of bacteria with interfering capacity was found in 30% of children with RATP, while in children without RATP it was found in as many as 85% of cases. Tonsillopharyngitis treatment: Current evidence suggests that the decrease in the number of acute tonsillopharyngitis episodes can be achieved with long-term prophylactic administration of cefpodoxime or 10-day course of clindamycin. Spontaneous resolution occurs in a number of patients, therefore the antibiotic treatment in the absence of an acute infection is not recommended. Penicillin should not be used in cases of confirmed presence of BLPB, when there is coaggregation of GABHS with Moraxella catarrhalis, in cases of absence of bacteria with interfering capacity, in patients that experienced failure of GABHS eradication with previous treatment, in recurrent GABHS tonsillopharyngitis, in the community with a high degree of unsuccessful treatment with penicillin (resistant bacterial strains) and in cases of allergic reaction to penicillin. The national guideline of good clinical practice for rational use of antibiotics does not recommend amoxicillin with clavulanate as the antibiotic of choice in the treatment of acute tonsillitis; also, according to other guidelines it is not the antibiotic of the first choice in recurrent tonsillitis. Macrolides were used as an effective alternative to penicillin, however, over time GABHS developed high resistance to macrolides and they should not be used routinely for the treatment of acute tonsillopharyngitis. Clindamycin has shown superiority in the tonsillar GABHS eradication of patients with RATP. Cephalosporins have been shown to be quite effective in patients with prior treatment failure or with RATP. High efficacy of cephalosporins is based on the ability to eradicate GABHS as well as concomitant BLPB and preserve interfering, protective bacterial strains. Conclusion: Tonsillectomy is recommended in patients with RATP. Antibiotic treatment may be offered to patients who do not meet criteria for tonsillectomy, in spite of their suffering from recurrent infections and to patients with contraindications or reluctance to tonsillectomy. Penicillin is not effective in eradicating GABHS and BLPB, as well as preventing future acute infections in patients with RATP, therefore it is preferable to use broad-spectrum antibiotics, such as cephalosporins. Prophylactic use of antibiotics in the treatment of RATP is not recommended.

Prevalence and Antibiogram of Extended-Spectrum Beta-Lactamase Producing Gram-negative Bacteria Isolated from Septicemic Neonates in a Tertiary Care Hospital

Background: In recent years, Extended-spectrum beta-lactamase (ESBL) producing microorganisms have complicated treatment of infections due to resistance of ESBL producing strains to a wide range of antimicrobials.
 Objective: Target of this study was to determine the prevalence of ESBL producing gramnegative bacteria in neonatal sepsis cases and to reveal the antimicrobial susceptibility pattern of those isolated ESBL producers.
 Materials and Methods: This cross sectional study was carried out in Dhaka Medical College Hospital (DMCH) over a period of 12 months from January to December in 2016. Following isolation and identification of gram-negative bacteria from blood samples of suspected septicemic neonates, antimicrobial susceptibility test was performed by Kirby Bauer disk-diffusion method and ESBL producers were detected by Double Disk Synergy (DDS) test.
 Results: Among 52 Gram-negative bacteria isolated from 106 blood samples, 34.61% ESBL producers were detected and Enterobacter spp. (45%) was predominant followed by Klebsiella pneumoniae (33.33%). None of the ESBL producers was resistant to colistin and tigecycline. All ESBL producing Acinetobacter baumannii, 77.78% and 66.67% of ESBL producing Enterobacter spp and Klebsiella spp. respectively showed resistance to meropenem. All ESBL producers were resistant to piperacillintazobactam.
 Conclusion: Appropriate measures should be taken to prevent the spread of ESBL producing strains by combining strategies for infection prevention, control and rational use of antibiotics.
 KYAMC Journal Vol. 11, No.-4, January 2021, Page 171-175

Prevalence of ESBL, AmpC and Carbapenemase-Producing Enterobacterales Isolated from Raw Vegetables Retailed in Romania.

(1) Background: As β-lactamase-producing Enterobacterales are no longer exclusively associated with the health care system, investigating the potential risk they pose to the integrity of the environment and food safety has become of utmost importance. This study aimed to determine the prevalence of extended-spectrum β-lactamase (ESBL), AmpC, and carbapenemase-producing Enterobacterales isolates from retailed raw vegetables and to determine if household washing is an effective method of lowering bacterial load; (2) Methods: Seasonal vegetables (n = 165) were acquired from supermarkets (n = 2) and farmer markets (n = 2) in Romania. Following sample processing and isolation, identification of Enterobacterales was performed by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF). Polymerase chain reaction (PCR) multiplex was used to ascertain the presence of the main ESBL, AmpC, and Carbapenemase genes. Phenotypic antibiotic resistance profiles of isolates were determined by extended antibiograms. Enterobacteriaceae colony-forming units (CFU) counts were compared between vegetable types; (3) Results: Beta-lactamase producing bacteria were observed on 7.9% of vegetables, with 5.5% displaying ESBL/AmpC phenotype and 2.4% identified as Carbapenemase producers. The most frequently detected β-lactamase genes were blaSHV (n = 4), followed by blaCTX-M and blaTEM (each with n = 3). Phenotypic antibiotic resistance analysis showed that 46% of isolates were multiple drug resistant, with aminoglycosides (38.5%) the most prevalent non-β-lactam resistance, followed by first-generation quinolones (38.5%). (4) Conclusions: The present study has described for the first time the presence of β-lactamase producing Enterobacterales in fresh produce retailed in Romania.

Prevalence of New Delhi Metallo Beta-Lactamase (NDM) Producing Gram-Negative Bacteria from Different Tertiary Care Hospitals in Lahore, Pakistan

Prevalence of New Delhi Metallo Beta-Lactamase (NDM) Producing Gram-Negative Bacteria from Different Tertiary Care Hospitals in Lahore, Pakistan

Assessment of Foods and Drinks for the Presence of Extended Spectrum Beta Lactamase (ESBL) Producing Bacteria in Gombe Metropolis, Nigeria

Objectives: To make preliminary screening study for the presence of ESBL producing bacteria, in food and drinks sold in Gombe metropolis. 30 samples of food and drinks were collected and analyzed. Method: Bacterial isolation was performed on nutrient agar and identification started from gram staining; the gram negative isolates obtained, among which ESBL producers were found and further subjected to standard biochemical tests and confirmed to be enterobacteriaceae. They were then screened for ESBLs in accordance with Clinical and Laboratory Standard Institute (CLSI) breakpoint, and the suspected ESBLs bacteria were confirmed using double disc synergy testing (DDST) with standard Augmentin (Amoxycillin/ Clavulanic Acid, 30μg; Oxoid England, CT0223B), Ceftriaxone (CRO 30μg; Oxoid England, CT0417B) and Ceftazidime (CAZ 30μg; Oxoid England, CT0412B). Findings: The fourteen 14(100%) Gram negative bacteria isolated were found to include Pseudomonasaeruginosa 2(14.29%) and members of the family Enterobacteriaceae (enteric gram negative rods): Citrobacterfreundii 2(14.29%), Enterobacterspp. 1(7.14%), Escherichiacoli 4(28.57%), Klebsiellapneumoniae 3(21.43%), Proteusvulgaris 1(7.14%) and Salmonellatyphi 1(7.14%). When screened for ESBL production based on CLSI breakpoint, only 6 (49.99%) were positive and included C.freundii 1(7.14%), E.coli 2(14.29%), K.pneumoniae 1(7.14%), S. typhi 1(7.14%) and 1(7.14%) for Ps. aeruginosa. On subjecting them to DDST, only 2(33.34%) out of them were found to be ESBLs positive by an increase in inhibition zone of 5mm toward the centre disc, Augmentin. They include E. coli 1(16.67%) and S. typhi 1(16.67%). Application: In a nutshell, foods and drinks sold therein could serve as reservoirs for ESBLs producing bacteria.

Assessment of Foods and Drinks for the Presence of Extended Spectrum Beta Lactamase (ESBL) Producing Bacteria in Gombe Metropolis, Nigeria

Objectives: To make preliminary screening study for the presence of ESBL producing bacteria, in food and drinks sold in Gombe metropolis. 30 samples of food and drinks were collected and analyzed. Method: Bacterial isolation was performed on nutrient agar and identification started from gram staining; the gram negative isolates obtained, among which ESBL producers were found and further subjected to standard biochemical tests and confirmed to be enterobacteriaceae. They were then screened for ESBLs in accordance with Clinical and Laboratory Standard Institute (CLSI) breakpoint, and the suspected ESBLs bacteria were confirmed using double disc synergy testing (DDST) with standard Augmentin (Amoxycillin/ Clavulanic Acid, 30μg; Oxoid England, CT0223B), Ceftriaxone (CRO 30μg; Oxoid England, CT0417B) and Ceftazidime (CAZ 30μg; Oxoid England, CT0412B). Findings: The fourteen 14(100%) Gram negative bacteria isolated were found to include Pseudomonasaeruginosa 2(14.29%) and members of the family Enterobacteriaceae (enteric gram negative rods): Citrobacterfreundii 2(14.29%), Enterobacterspp. 1(7.14%), Escherichiacoli 4(28.57%), Klebsiellapneumoniae 3(21.43%), Proteusvulgaris 1(7.14%) and Salmonellatyphi 1(7.14%). When screened for ESBL production based on CLSI breakpoint, only 6 (49.99%) were positive and included C.freundii 1(7.14%), E.coli 2(14.29%), K.pneumoniae 1(7.14%), S. typhi 1(7.14%) and 1(7.14%) for Ps. aeruginosa. On subjecting them to DDST, only 2(33.34%) out of them were found to be ESBLs positive by an increase in inhibition zone of 5mm toward the centre disc, Augmentin. They include E. coli 1(16.67%) and S. typhi 1(16.67%). Application: In a nutshell, foods and drinks sold therein could serve as reservoirs for ESBLs producing bacteria.

Microbiology of chronic rhinosinusitis.

Most sinus infections are viral and only a small percentage develop bacterial infection. Rhino-, influenza, and para-influenza viruses are the most frequent viral causes of sinusitis. The most common bacterial isolates from children and adult patients with community-acquired acute bacterial sinusitis are Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catarrhalis, and Streptococcus pyogenes. Staphylococcus aureus and anaerobic organisms (Prevotella and Porphyromonas, Fusobacterium, and Peptostreptococcus spp.) are the commonest isolates in chronic rhinosinusitis (CRS). Aerobic and anaerobic beta lactamase-producing bacteria (BLPB) were recovered from over a third of these patients. Methicillin-resistant S. aureus (MRSA) accounted for over 60% of S. aureus isolates. Pseudomonas aeruginosa and other aerobic and facultative Gram-negative rods are frequently recovered in nosocomial sinusitis, the immunocompromised host, individuals with human immunodeficiency virus infection, and in cystic fibrosis. The CRS infection evolves the formation of a biofilm that might play a significant role in the pathogenesis and persistence of CRS. The microbiology of sinusitis is influenced by previous antimicrobial therapy, vaccinations, and the presence of normal flora capable of interfering with the growth of pathogens. Recognition of the unique microbiology of CRS and their antimicrobial susceptibility is of great importance when selecting antimicrobial therapy.

Penicillin failure in the treatment of group A streptococcal pharyngo-tonsillitis: Causes and solutions

Despite its in vitro efficacy, the increased inability of penicillin to eradicate Group A beta-hemolytic streptococci (GABHS) from patients with acute and relapsing pharyngo-tonsillitis (PT) is of great concern. This review describes the causes of penicillin failure in eradicating GABHS PT. These include the presence of beta-lactamase producing bacteria (BLPB) that protect GABHS from penicillins; the absence of bacteria that interfere with the growth of GABHS; co-aggregation between GABHS and Moraxella catarrhalis; and the poor penetration of penicillin into the tonsillar tissues and the tonsillo-pharyngeal cells which allows intracellular GABHS and Staphylococcus aureus to survive. The inadequate intracellular penetration of penicillns can allow intracellular GABHS and S. aureus to persist. In the treatment of acute tonsillitis, the use of cephalosporins can overcome these interactions by eradicating aerobic BLPB (including M. catarrhalis), while preserving the potentially interfering organisms and eliminating GABHS. In treatment of recurrent and chronic PT the administration of clindamycin, or amoxicillin-clavulanic acid can eradicate both aerobic and anaerobic BLPB as well as GABHS. The superior intracellular penetration of cephalosporins and clindamycin enhances their efficacy against intracellular GABHS and S. aureus.

Synergy and Mode of Action of Ceftazidime plus Quercetin or Luteolin on Streptococcus pyogenes.

Streptococcus pyogenes causes streptococcal toxic shock syndrome. The recommended therapy has been often failure through the interfering of beta-lactamase-producing bacteria (BLPB). The present study was to investigate antibacterial activity, synergy, and modes of action of luteolin and quercetin using alone and plus ceftazidime against S. pyogenes. The MICs of ceftazidime, luteolin, and quercetin against all S. pyogenes were 0.50, 128, and 128 µg mL−1, respectively. A synergistic effect was exhibited on luteolin and quercetin plus ceftazidime against these strains at fractional inhibitory concentration indices 0.37 and 0.27, respectively, and was confirmed by the viable count. These combinations increased cytoplasmic membrane (CM) permeability, caused irregular cell shape, peptidoglycan, and CM damage, and decreased nucleic acid but increased proteins in bacterial cells. Enzyme assay demonstrated that these flavonoids had an inhibitory activity against β-lactamase. In summary, this study provides evidence that the inhibitory mode of action of luteolin and quercetin may be mediated via three mechanisms: (1) inhibiting of peptidoglycan synthesis, (2) increasing CM permeability, and (3) decreasing nucleic acid but increasing the protein contents of bacterial cells. So, luteolin and quercetin propose the high potential to develop adjunct to ceftazidime for the treatment of coexistence of the BLPB and S. pyogenes infections.

Epidemiology of infections due to extended-spectrum Beta-lactamase-producing bacteria in a pediatric intensive care unit.

To determine the proportion of infections caused by extended-spectrum ß-lactamase (ESBL)-producing Klebsiella or Escherichia coli Gram-negative organisms in the pediatric intensive care unit (PICU), and to identify risk factors for these infections. A retrospective, single-center chart review of patients admitted to a PICU in a 5-year period with infections caused by Klebsiella species or E coli was completed. Data collected include demographics, length of stay, outcome, and relevant risk factors previously defined in the literature. A total of 110 isolates were cultured from 94 patients. A total of 53% of the isolates were E coli, and the remainder were Klebsiella subspecies. Of the 110 isolates, 13 isolates (11.8%) in 7 patients were ESBL positive. The ESBL-producing isolates were equally distributed amongE coli and Klebsiella and were primarily cultured from tracheal aspirates. Most of the ESBL-positive isolates (9 of 13; 69%) were cultured from patients who received ceftazidime and/or cefotaxime in the preceding 30 days. Patients infected with E coli had higher PRISM 1 scores and were more likely to have a Foley catheter, whereas infections with Klebsiella were more common in mechanically ventilated males. Although not statistically significant, 80% of patients who were infected with non-ESBL-producing organisms survived to hospital discharge versus 57% of those infected with ESBL-producing E coli and Klebsiella. Almost 12% of E coli and Klebsiella isolates in this patient population tested positive for ESBL production. ESBL production was equally distributed between E coli and Klebsiella species. These organisms were cultured from 7% of the study patients. As reported in previous studies, patients infected with ESBL-producing organisms most often had received prior cephalosporins and had a longer length of stay in the PICU.

Leaf Extracts of Vernonia amygdalina Del. from Northern Ghana Contain Bioactive Agents that Inhibit the Growth of Some Beta-lactamase Producing Bacteria in vitro

Aims: The current study was aimed at evaluating the phytochemical profile and in vitro bacteria growth inhibitory potential of different solvent leaf extracts of V. amygdalina from northern Ghana. Study Design: Different solvent extracts of the plant were quantitatively and qualitatively evaluated for phytochemicals. In vitro bacteria sensitivity assay of the extracts was evaluated using some beta-lactamase producing bacteria as test microbes. Methodology: Ethanolic, methanolic, petroleum ether and aqueous leaf extracts of Vernonia amygdalina were studied in vitro for growth inhibition against beta-lactamase producing bacteria such as Escherichia coli, Staphylococcus aureus, Klebsiella pneumoniae and Pseudomonas aeruginosa using agar well diffusion method. Saponins, flavonoids, glycosides, alkaloids, tannins, phenolics, reducing sugars, anthracenosides, terpenes and phytosteroids were determined qualitatively and quantified. Results: All the phytochemicals tested were found to be present in both the methanolic and ethanolic leaf extracts. The aqueous extract showed the presence of saponins, reducing sugars and anthracenosides. Glycosides, flavonoids, saponins and alkaloids were the only groups of phytochemicals found in the petroleum ether extract. The methanolic extract showed the greatest amount of saponins (14.23%), flavonoids (2.15%), alkaloids (7.49%), tannins (5.4%), terpenes (10.20%) and phenolics (8.24%). The methanolic extract at concentration of 4 mg/ml showed growth inhibitory activities against all the test organisms with zone of inhibitions ranging from 16.00+0.50 (against E. coli) to 20.50+0.03 mm (against S. aureus). The ethanolic extract showed activity against only two of the test organisms viz. 23.00+0.33 mm against P. aeruginosa and 12.00+0.00 mm against S. aureus at similar concentration. All test organisms were resistant to both aqueous and pet ether extracts. Conclusion: The antibacterial activities of the methanolic and ethanolic extracts were significant (P < 0.05) and may be mediated by the presence of saponins, flavonoids, tannins, terpenes and alkaloids. Results from present study corroborate previous findings and also presents methanolic leaf extract of the plant as a credible candidate for the discovery of new phytotherapeutic agents against the beta-lactamase producing bacteria tested.

Isolation of beta-lactamase producing bacteria — the reality of a differentiated hospital

Beta-lactamase producing bacteria (BLPB) are responsible for severe nosocomial infections, difficult to control and which constitute an important and growing public health problem, with respect to antibiotic resistance. Objective: This study intended to characterize patients with cultures positive for BLPB, characterize the population susceptible to infection with BLPB, and the resistance profile of these agents, and identify risk factors for this infection as well as potential associated complications and mortality. Methods: This was a descriptive retrospective study, made in the hospital in question during a 9 month period (2012 January 1 to September 15), by consulting clinical processes, at a time when there was a substantial increase in these infections in our hospital. Results: We identified 332 isolates (242 cultures with Escherichia coli and 90 Klebsiella pneumoniae), corresponding to 191 patients. Of these 67% were considered infections associated with health care, 24% of community infections and 9% colonization. The average age of these patients was 69.5 years, the majority being female. The average hospital days stood at 20.9 days and the mean time between admission and positive culture was 7.4 days. In more than 90% of the patients noted the presence of invasive devices. 65% of patients had a history of hospitalization in the previous 3 months, 59% had done last month antibiotic treatment (beta-lactams, cephalosporins and quinolones) and 51% had both factors. The existence of comorbidities was also studied and found that hypertension, diabetes mellitus, cerebrovascular disease, heart disease and chronic kidney disease were the most prevalent. It was also found that the most frequent sites of isolation were the urinary tract and blood (21.7% of bacteraemia). 38.3% of these patients with an overall mortality of 19% were readmitted. All of these bacteria were sensitive to carbapenem, except two cases which were sensitive only to amikacin and tigecycline. Conclusion: Elderly patients with more pathologies, with previous antibiotics or hospitalization, and with invasive devices have more susceptibility to infectious by beta-lactamase producing bacteria. Identifying groups and factor risks is important to take effective control infection measures.

Pulmonary mucormycosis in a patient with systemic vasculitis

Beta-lactamase producing bacteria (BLPB) are responsible for severe nosocomial infections, difficult to control and which constitute an important and growing public health problem, with respect to antibiotic resistance. Objective: This study intended to characterize patients with cultures positive for BLPB, characterize the population susceptible to infection with BLPB, and the resistance profile of these agents, and identify risk factors for this infection as well as potential associated complications and mortality. Methods: This was a descriptive retrospective study, made in the hospital in question during a 9 month period (2012 January 1 to September 15), by consulting clinical processes, at a time when there was a substantial increase in these infections in our hospital. Results: We identified 332 isolates (242 cultures with Escherichia coli and 90 Klebsiella pneumoniae), corresponding to 191 patients. Of these 67% were considered infections associated with health care, 24% of community infections and 9% colonization. The average age of these patients was 69.5 years, the majority being female. The average hospital days stood at 20.9 days and the mean time between admission and positive culture was 7.4 days. In more than 90% of the patients noted the presence of invasive devices. 65% of patients had a history of hospitalization in the previous 3 months, 59% had done last month antibiotic treatment (beta-lactams, cephalosporins and quinolones) and 51% had both factors. The existence of comorbidities was also studied and found that hypertension, diabetes mellitus, cerebrovascular disease, heart disease and chronic kidney disease were the most prevalent. It was also found that the most frequent sites of isolation were the urinary tract and blood (21.7% of bacteraemia). 38.3% of these patients with an overall mortality of 19% were readmitted. All of these bacteria were sensitive to carbapenem, except two cases which were sensitive only to amikacin and tigecycline. Conclusion: Elderly patients with more pathologies, with previous antibiotics or hospitalization, and with invasive devices have more susceptibility to infectious by beta-lactamase producing bacteria. Identifying groups and factor risks is important to take effective control infection measures.

Penicillin Failure in the Treatment of Streptococcal Pharyngo-Tonsillitis

The inadequate penetration of penicillins into the tonsillar tissues and tonsillar surface fluid and microbiologic interactions between Group A beta-hemolytic streptococci (GABHS) and other pharyngo-tonsillar bacterial flora can account for their failure in eradicating GABHS pharyngo-tonsillitis (PT). These interactions include the presence of beta-lactamase producing bacteria (BLPB) that "shield" GABHS from penicillins, the absence of bacteria that interfere with the growth of GABHS, and the coaggregation between GABHS and Moraxella catarrhalis. In the treatment of acute tonsillitis, the use of cephalosporins can overcome these interactions by eradicating aerobic BLPB, while preserving the potentially interfering organisms and eliminating GABHS. In treatment of recurrent and chronic PT, the administration of clindamycin or amoxicillin-clavulanatecan eradicates both aerobic and anaerobic BLPB, as well as GABHS.

The Role of Beta-Lactamase-Producing-Bacteria in Mixed Infections I Children

Beta-lactamase-producing bacteria (BLPB) can play an important role in polymicrobial infections. They can have a direct pathogenic impact in causing the infection as well as an indirect effect through their ability to produce the enzyme beta-lactamase. BLPB may not only survive penicillin therapy but can also, as was demonstrated in in vitro and in vivo studies, protect other penicillin-susceptible bacteria from penicillin by releasing the free enzyme into their environment. This phenomenon occurs in upper respiratory tract, skin, soft tissue, surgical and other infections. The clinical, in vitro, and in vivo evidence supporting the role of these organisms in the increased failure rate of penicillin in eradication of these infections and the implication of that increased rate on the management of infections is discussed. Penicillins have been the drugs of choice for the treatment of a variety of bacterial infections in children. However, within the past six decades, an increased resistance to these agents has been observed. In addition to organism long known to resistant beta-lactamases, such as Staphylococcus aureus and Enterobacteriaceae, other previously susceptible bacteria became increasingly resistant to these agents due to several mechanisms including the production of the enzyme beta-lactamase (BL). These organisms include aerobic and facultative bacteria such as Haemophilus influenzae, Moraxella catarrhalis, as well as anaerobic Gram-negative bacilli (AGNB, i.e. Bacteroidesfragilis group, pigmented Prevotella and Porphyromonas, Prevotellabivia, and Prevotella disiens) and Fusobacterium spp.) [1-3]. Beta-lactamase-producing bacteria (BLPB) can have an important clinical role in clinical infections. These bacteria can be pathogenic in their own merit as well as have an indirect effect through their ability to produce the enzyme BL into their surroundings. BLPB may not only survive penicillin therapy but also may shield other beta-lactamesusceptible bacteria from these agents by releasing the enzyme into their surroundings ( Figure 1) [4]. *Corresponding author: Itzhak Brook, Department of Pediatrics, Georgetown University School of Medicine, MD, MSc, 4431 Albemarle St. NW, Washington DC 20016, USA, Tel : 202 363 4253; E-mail: ib6@georgetown.edu Received August 08, 2011; Accepted January 05, 2012; Published January 09, 2012 Citation: Brook I (2012) The Role of Beta-Lactamase-Producing-Bacteria in Mixed Infections I Children. Pediatr Therapeut 2:e105. doi:10.4172/2161-0665.1000e105 Copyright: © 2012 Brook I. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Microbiology of Acute and Chronic Maxillary Sinusitis in Smokers and Nonsmokers

We evaluated the microbiology of sinus aspirates of smokers and nonsmokers with acute and chronic maxillary sinusitis. Cultures were obtained from 458 patients, 244 (87 smokers and 157 nonsmokers) of whom had acute maxillary sinusitis and 214 (84 smokers and 130 nonsmokers) of whom had chronic maxillary sinusitis, between 2001 and 2007. A greater number of Staphylococcus aureus, methicillin-resistant S aureus (MRSA), and beta-lactamase-producing bacteria (BLPB) were found in the 87 smokers with acute sinusitis than in the nonsmokers with acute sinusitis (p < 0.005, p < 0.025, and p < 0.05, respectively). A greater number of these organisms were found in the 84 smokers with chronic sinusitis than in the nonsmokers (p < 0.01, p < 0.025, and p < 0.001, respectively). Eighty-five BLPB isolates were recovered from 73 patients (30%) with acute sinusitis. These included Moraxella catarrhalis, S aureus, Haemophilus influenzae, Prevotella spp, and Fusobacterium spp; 40 BLPB isolates were found in smokers, and 45 in nonsmokers (p < 0.05). One hundred twenty-five BLPB isolates were recovered from 91 patients (43%) with chronic sinusitis, including M catarrhalis, Bacteroides fragilis group, S aureus, H influenzae, Prevotella spp, and Fusobacterium spp; 69 BLPB isolates were found in smokers, and 56 in nonsmokers (p < 0.001). Antimicrobial therapy had been administered in the past month to 130 patients (28%; 60 smokers and 70 nonsmokers; p <0.025). Both MRSA and BLPB were isolated more often from these individuals (p < 0.025). However, the higher isolation rates of MRSA and BLPB in smokers were independent of previous antimicrobial therapy. These data illustrate a greater frequency of isolation of S aureus, MRSA, and BLPB in patients with acute and chronic sinusitis who smoke.

Clinical and economic outcomes associated with community-acquired intra-abdominal infections caused by extended spectrum beta-lactamase (ESBL) producing bacteria in China

Background:To compare clinical and economic outcomes in patients with community-acquired intra-abdominal infection (IAI) due to extended spectrum beta-lactamase (ESBL) producing (ESBL-positive) bacteria versus non-ESBL-producing (ESBL-negative) bacteria in China.Methods:This was a retrospective chart review study of patients hospitalized with community-acquired IAI due to ESBL-positive or ESBL-negative infections caused by Escherichia coli or Klebsiella spp. Data were collected from six hospitals in China that participated in the Study for Monitoring Antibiotic Resistance Trends (SMART) during 2006–2007. Outcomes included clinical response at discharge and following first-line antibiotic, number of antibiotic agents and classes, duration of hospitalization, and overall hospitalization and intravenous antibiotic costs.Results:Of the 85 patients included in the study, 32 (37.6%) had ESBL-positive and 53 (62.4%) had ESBL-negative infections; E. coli was responsible for 77.6% of infections. Infection resolved at discharge in 30 (93.8%) ESBL-positive and 48 (90.6%) ESBL-negative patients (P = NS). Fewer ESBL-positive patients achieved complete response following first-line antibiotics (56.3% versus 83.0%; P = 0.01). ESBL-positive patients required longer antibiotic treatment, more antibiotics, longer hospitalization (24.3 versus 14.6 days; 1.67-fold ratio; P = 0.001), and incurred higher hospitalization costs (¥24,604 vs. ¥13,788; $3604 vs. $2020; 1.78-fold ratio; P < 0.001).Conclusions:Patients with ESBL-positive infection had similar resolution rates at discharge compared to those with ESBL-negative infection, despite poorer first-line antibiotic response. However, ESBL-positive infection led to significantly greater hospitalization cost and intravenous antibiotic cost, and longer hospital stay.