Characterization of third generation cephalosporin-resistant Escherichia coli clinical isolates from Ushuaia, Argentina / Caracterización de aislamientos clínicos de Escherichia coli resistente a cefalosporinas de tercera generación de Ushuaia, Argentina

Abstract Escherichia coli is one of the main human pathogens causing different hospital- and community-acquired infections. During the period from January 2013 to March 2015, 1.96% (32/1632) of E. coli isolates recovered at the Hospital Regional de Ushuaia, Tierra del Fuego province, were resistant to third-generation cephalosporins (TGCs). These isolates were resistant to cefotaxime (91%) and/or ceftazidime (28%). No resistance to carbapenems was detected. Twenty-six isolates were positive for blaCTX-M gene, grouped as CTX-M-1/15 (54%); CTX-M-9/14 (25%); CTX-M-2 (17%); and CTX-M-1/15 plus CTX-M-9/14 (4%). Five TGC-resistant strains were positive for blaCMY gene, while one strain harbored TEM-19 ESBL. Twelve isolates were identified as ST131 E. coli hyperepidemic clone, and one as ST69. Genome sequence analysis of seven blaCTX-M-15 E. coli selected isolates confirm the circulation of ST131, ST617 and ST405 international high-risk clones in the city of Ushuaia.

Resumen Escherichia coli es uno de los principales patógenos humanos causantes de diferentes infecciones de inicio hospitalario y comunitario. Se determinó que el 1,96% (32/1.632) de los aislamientos de E. coli recuperados entre enero de 2013 y marzo de 2015 en el Hospital Regional de Ushuaia, provincia de Tierra del Fuego, fueron resistentes a cefalosporinas de tercera generación (CTG). Estos aislamientos fueron resistentes a cefotaxima (91%) y/o a ceftazidima (28%). No se detectó resistencia a los carbapenemes. Veintiséis aislamientos fueron positivos para el gen blaCTX-M, agrupados como CTX-M-1/15 (54%), CTX-M-9/14 (25%), CTX-M-2 (17%) y CTX-M-1/15 más CTX-M-9/14 (4%). Cinco cepas resistentes a CTG dieron positivo para el gen blaCMY, mientras que un aislamiento presentó la BLEE TEM-19. Doce aislamientos se identificaron como clon hiperepidémico E. coli ST131 y uno como ST69. El análisis de las secuencias del genoma de siete aislamientos seleccionados de E. coli blaCTX-M-15 confirmó la circulación de los clones internacionales de alto riesgo ST131, ST617 y ST405 en la ciudad de Ushuaia.

Cefiderocol: a novel siderophore cephalosporin against multi-drug resistant Gram-negative bacilli infections / 生物工程学报

Antimicrobial resistance is one of the critical public health issues in the world. There is an urgent need to develop effective broad-spectrum antibiotics to treat the infection of multi-drug resistant Gram-negative bacilli. Cefiderocol, developed by the Shionogi Inc. in Japan, is a new type of iron carrier cephalosporin antibiotics, which overcomes the drug resistance of Gram-negative bacilli due to the down-regulation of outer membrane pore protein and the up-regulation of efflux pump, and has good stability to serine- and metallo-carbapenemases. This drug has a broad spectrum and strong antibacterial activity against carbapenem-resistant Enterobacteriaceae (CRE), Pseudomonas aeruginosa, Acinetobacter baumannii, and Stenotrophomonas maltophilia. Cefiderocol can be used to treat complex urinary tract infections (including pyelonephritis), hospital-acquired pneumonia, and ventilator-associated pneumonia. By summarizing the chemical structure, antibacterial mechanism, in vitro antibacterial activity, pharmacokinetics, pharmacodynamics, and clinical treatment of cefiderocol, this review shows the application potential of cefiderocol as a new iron carrier cephalosporin in the treatment of multi-drug resistant Gram-negative bacilli infections.

Synthesis and antibacterial activity of C-7 haloacyl cephalosporins / 药学学报

Cephalosporins are widely used in the treatment of infectious diseases. The structural differences in cephalosporin drugs mainly lie in the C-7 amino side chain and the C-3 substituent. In this study, twenty-five haloacylated cephalosporins of five series were designed by using a strategy of introducing simple substituents at the C-7 amino group in four cephalosporin parent nucleus with different C-3 substituents and efficiently synthesized under optimized conditions. Their activities against human pathogenic bacteria, Pichia pastoris, citrus canker and citrus pathogenic fungi were evaluated. The results showed that most of the molecules had activity against human pathogenic bacteria, of which seven compounds including TM1f had stronger or equivalent inhibitory activities against eight human pathogens than the marketed drugs cefalotin, cefoxitin sodium and ceftizoxime sodium. The inhibitory activity of TM1s against Alternaria alternate Al.6 was stronger than that of cephalosporins and comparable to that of the positive control prochloraz. TM1f and TM1s are worthy of further study.

The Outpatient Prescribing Pattern of Cefuroxime in Al-Kharj

Introduction:Several previous studies reported a high prescribing rate of cephalosporin antibiotics such as cefuroxime. The inappropriate outpatients prescribing of cefuroximeleadsto the development of bacterial resistance.Aim: This study was conducted to demonstrate the prescribing pattern of cefuroxime in the outpatient setting in Alkharj.Methodology:This retrospective study was conducted to know the prescribing pattern of cefuroxime. The data were collected from electronic prescriptions in a public hospital in Alkharj in 2018. The data were collected and analyzed using Excel software and represented as frequencies and percentages.Results:In 2018, there were 316 prescriptions containing cefuroxime. The majority of the patient wasmales (56.01%). The majority of cefuroxime prescriptions include tablet dosage form (81.96%). About 62.03% of the outpatient prescriptions were prescribed by the emergency department.Conclusion:Cephalosporin group (including cefuroxime) was one of the most commonly prescribed antibiotic groups to treat several infections. A high percentage of antibiotic prescriptions were prescribed inappropriately. It is important to increase the awareness about the wise use of antibiotics and to start the implementation of antimicrobial stewardship programs.

A prospective study on pattern of superficial surgical site infections in patients undergoing emergency laparotomy for perforation peritonitis

Background: surgical site infections (SSIs) are recognized as a common surgical complication occurring in about 3% of all surgical procedures and in upto 20% of patients undergoing emergency intraabdominal procedures. Aims: To determine the incidence of SSIs in emergency laparotomies done for perforation peritonitis and the organisms involved and their sensitivity pattern in superficial SSI. The objective of the study was to determine the effect of planned intra operative intervention [antibiotic lavage with III generation cephalosporin e.g. ceftriaxone 1 gm and metronidazole 100 ml (5 mg per ml)] on superficial surgical site infection in emergency laparotomies done for perforation peritonitis.Methods: This prospective randomized case controlled study was carried out in P. G. Department of Surgery, S. R. N. Hospital associated with M. L. N. Medical College, Allahabad, from September 2018 to August 2019 after approval from the ethical committee and after obtaining written and informed consent either from patient or their guardian. Patients were divided into two groups viz. control group receiving the normal saline lavage and case group receiving the antibiotic lavage (III generation cephalosporins i.e., ceftriaxone (1 gm in 1000 ml NS) and metronidazole- 5 mg/ml (100 ml in 500 ml NS).Results: There is almost 50% incidence of SSI in emergency laparotomy done for perforation peritonitis. The most common organism involved in superficial SSI in present study was gut flora (E. coli) followed by normal skin colonizer (Staph. aureus).Conclusions: Intraperitoneal antibiotic lavage has a significant role in reducing the rate of SSI especially in gastroduodenal perforations.

Antibiotic resistance profile in intrahospital pediatric services at third level centers in Dominican Republic / Perfil de resistencia a antibióticos en servicios pediátricos intrahospitalarios en centros de tercer nivel en República Dominicana

Objectives: The Dominican Republic lacks reliable information on antimicrobial resistance (AMR), which would allow physicians to prescribe the best treatment for common infectious diseases. This study aimed to define the antimicrobial resistance profiles of the more common pathogens from pediatric services, where data is even more important due to the vulnerability of the population. Methods: We collected data from patients admitted in the pediatric unit of three third level hospitals in the city of Santiago de los Caballeros, Dominican Republic, showing positive bacterial cultures, during a period of two years. Results: Half of the Gram negative pathogens exhibited third generation cephalosporins (3GC) resistance, 17% were resistant to carbapenems. Serratia marcescens presented an exceptionally high proportion of resistance to 3GC (95.9%). Staphylococcus aureus showed elevated resistance to methicillin (58.4%) and even to clindamycin (35.8%). Conclusion: There are elevated levels of antimicrobial resistance among the Enterobacteriaceae family and the Staphylococcus genus isolated from the pediatric population. Necessary measures should be taken to tackle AMR in the country.

Objetivos: La República Dominicana carece de información confiable sobre las resistencias antimicrobianas en el país, lo que permitiría al personal médico prescribir los mejores tratamientos para infecciones comunes. El objetivo de este estudio es definir los perfiles de resistencia antimicrobiana de los patógenos más comunes en servicios pediátricos, donde esta información es esencial, debido a la vulnerabilidad de la población. Métodos: Se tomaron los datos de reportes microbiológicos con cultivo bacteriano positivo procedentes de pacientes admitidos en la unidad pediátrica de tres hospitales de tercer nivel en la ciudad de Santiago de los Caballeros, República Dominicana, durante un periodo de dos años. Resultados: La mitad de los patógenos Gram negativos mostraron resistencia a cefalosporinas de tercera generación (3GC), 17% eran resistentes a carbapenémicos. Serratia marcescens presentó una resistencia excepcionalmente elevada a 3GC (95.9%). Staphylococcus aureus mostró alta resistencia a meticilina (58.4%) e incluso a clindamicina (35.8%). Conclusión: Existen elevados niveles de resistencia antimicrobiana entre las enterobacterias y los estafilococos en la población pediátrica dominicana. Es necesario tomar medidas para abordar este problema en el país.

Sand Dune Streptomyces Jb66 Native To The Great Indian Thar Desert Inhibits Multidrug-Resistant Pathogens

The efficacy of an actinomycete strain JB66 recovered from a sand dune soil from the Bikaner district of the Thar desert in inhibiting the growth of various bacterial pathogens was studied. The type strains Staphylococcus aureus, Shigella flexneri, Klebsiella pneumoniae and the clinical isolates Escherichia coli, multidrug-resistant S. aureus and P. vulgaris were included in the antimicrobial assays. Polyphasic characterization of JB66 isolate revealed its identity as Streptomyces (MH762010). It showed 88.99-89.24% sequence similarity with the other members of this genus and share the maximum (88.89%) similarity with Streptomyces sp. ATSC13. The strain JB66 was found to produce a high amount of extracellular L-asparaginase, catalase, gelatinase, protease, tyrosinase and urease enzymes. The partial chemical categorization of the methanolic crude extract of the JB66 strain led to the preliminary identification of various metabolic compounds. The thin-layer chromatography fractionation revealed the presence of prodigiosin pigment or chandramycin, cephalosporin or zeatin, daidzein, demethoxy rapamycin, 4,6-dihydroxy-7-methoxyisoflavone, munumbicins and amiclenomycin like compounds. Bio-autography revealed that the metabolites localized at the Rf values of 0.40, 0.46 and 0.53 in TLC profile had the actual bioactive fractions. UV-VIS spectrum absorbance maxima at 288 nm revealed the presence of an aromatic nucleus.

Cefixime induce non convulsive status epileptics: a neurotoxic effect

Nonconvulsive status epileptics comprises a group of syndromes that display a great diversity regarding response to anticonvulsants ranging from virtually self-limiting variants to entirely refractory forms cephalosporins are thought to provoke seizure through inhibitory effects on gamma-aminobutyric acid (GABA) transmission and GABA receptors. Interference with GABA transmission result in pre-disposition towards excitatory neurotransmission, which can leads to seizures. Antibiotics can alter the serum concentration of anti-epileptic, resulting in seizures and anti-epileptic drugs toxicity.

Resistencia de Staphylococcus aureus frente a cefalosporinas en la sepsis neonatal y puerperal / Staphylococcus Aureus Resistance against Cephalosporins in Neonatal and Puerperal Sepsis

Introducción: El mecanismo más común de actividad antibiótica es la interferencia en la síntesis de la pared celular bacteriana. Las cefalosporinas tienen el mismo mecanismo de acción que las penicilinas; sin embargo, tienen un espectro antibacteriano más amplio, son resistentes a muchas b-lactamasas y tienen propiedades farmacocinéticas mejoradas. Objetivos: Identificar por servicios los gérmenes aislados y determinar la resistencia del Staphylococcus aureus a las cefalosporinas. Método: Se realizó un estudio retrospectivo, transversal y descriptivo en hospital Ginecobstétrico de Guanabacoa desde enero de 2014 hasta diciembre de 2016. Se seleccionaron como variables los gérmenes aislados y el patrón de resistencia del germen que predominó frente a todas las generaciones de cefalosporinas. Resultados: En el servicio de neonatología el mayor aislamiento fue en el hemocultivo seguido del catéter venoso (19 pacientes) y tubo endotraqueal. En el servicio de Obstetricia, los loquios y el sitio quirúrgico fue donde se aisló mayor número (69 y 31 pacientes, respectivamente). Conclusiones: El germen más frecuente aislado en ambos servicios fue el Staphylococcus aureus y la resistencia a las cefalosporinas fue muy elevado(AU)

Introduction: The synthesis interference of bacterial cell wall is the most common antibiotic mechanism. Cephalosporins have the same mechanism of action as penicillin. However, they have wider antibacterial spectrum, they are more resistant to B-lactamases and better pharmacokinetics properties. Additionally, cephalosporins have higher activity in front of gram-negative bacteria than penicillin. Objective: To identify isolated germs in these services and to determine the Staphylococcus aureus resistance to cephalosporins. Method: A retrospective, transversal and descriptive study was conducted in Guanabacoa Gynecobstetric hospital from January 2014 to December 2016. selected variables as isolated microorganism, and resistance pattern in front of cephalosporin generations. The isolated germs and the resistance pattern of the germ that prevailed against all generations of cephalosporins were selected as variables. In the Obstetrics Service, the largest number of germs was isolated in the lochia and surgical sites. (69 and 31, respectively). Results: In neonatology service, the most frequent isolation occurred in blood culture (35), venous catheter (19) and endotracheal tube (10). In Obstetric service, the most frequent isolation occurred in liquors (69) and the surgical site isolated (31). Conclusions: Staphylococcus Aureus was the main microorganism isolated in hospital and its cephalosporin resistance was very high(AU)

Antimicrobial Profile of Clinical Isolates in Intensive Car e Unit at a Tertiary Care Hospital

Introduction: Intensive Care Units (ICU’s) provides a suitable environment for the proliferation and persistence of multidrug organisms. The burden of nosocomial infections among critically ill patients is much higher in developing countries. Aims and Objectives: The present study was conducted to know the prevalence of bacterial pathogens from various ICU’s of a tertiary care hospital and to determine their resistance profile. Materials and methods: A retrospective study was done on 188 isolates collected over a period of 10 months from January 2018 to October 2018. The isolates were identified by the conventional biochemical method and antimicrobial susceptibility testing was performed by Kirby bauer disc diffusion method. Results: The most common gram negative isolate obtained in this study was Klebsiella spp. About 90/188 (47.87%), followed by Pseudomonas aeruginosa 22/188 (11.70%), Acinetobacter spp. 21/188 (11.17%), and E. coli 20/188 (10.64%). The predominant gram positive cocci isolated were Enterococcus spp. 9/188 (4.79%). All gram negative bacilli were sensitive to Imipenem. About 23.33% of Klebsiella isolates were resistant to Piperacillin tazobactam and 18.89% to Cefoperazone sulbactam. The most effective drugs against gram negative bacilli were Imipenem, Piperacillin tazobactam, and Cefoperazone sulbactam. Conclusion: This study showed the prevalence of multidrug resistant Klebsiella spp. from various ICU’s. These isolates were resistant to third generation cephalosporins, quinolones, and aminoglycosides and were sensitive to carbapenems. Among the non-fermenting gram negative bacilli, the resistant rates were higher for Acinetobacter isolates compared to Pseudomonas aeruginosa.

Predictive factors for third-generation cephalosporin-resistant spontaneous bacterial peritonitis / 临床肝胆病杂志

ObjectiveTo investigate the predictive factors for third-generation cephalosporin-resistant spontaneous bacterial peritonitis (SBP). MethodsA retrospective analysis was performed for the clinical data of 206 patients with liver cirrhosis who were hospitalized in the Ninth Hospital of Nanchang from January 2010 to December 2018, and all patients had SBP with positive bacteria based on ascites culture. According to drug susceptibility results, the patients were divided into third-generation cephalosporin-resistant SBP group (101 patients with third-generation cephalosporin-resistant pathogenic bacteria in ascites) and control group (105 patients with pathogenic bacteria sensitive to third-generation cephalosporin). Electronic medical records were reviewed to collect related information. The t-test was used for comparison of normally distributed continuous data between groups, and the Mann-Whitney U test was used for comparison of data with skewed distribution between groups. The chi-square test or the Fisher’s exact test was used for comparison of categorical data between groups. A dichotomous logistic regression analysis was used for multivariate analysis, and the Forward: LR method was used for the screening of independent variables. ResultsThere was a significant difference in the composition of pathogenic bacteria between the two groups (P＜0.001). The univariate analysis showed that a history of broad-spectrum antibiotic exposure in the past three months (χ2=12.351, P＜0001), non-first-time onset of SBP (χ2=14.427, P＜0.001), blood creatinine (χ2=-2.537, P=0.011), and blood bicarbonate (χ2=-4.592, P＜0.001) were candidate predictive factors with statistical significance between the two groups, and further multivariate analysis showed that a history of broad-spectrum antibiotic exposure in the past three months (odds ratio ［OR］=2.376, 95% confidence interval ［CI］: 1.009-5.598, P=0.048), non-first-time onset of SBP (OR=2.841, 95%CI: 1.133-7.122, P=0.026), and blood bicarbonate (OR=0.892, 95%CI: 0.818-0.973, P=0.010) had an independent predictive value for third-generation cephalosporin-resistant SBP. ConclusionA history of broad-spectrum antibiotic exposure in the past three months, non-first-time onset of SBP, and a low level of blood bicarbonate are independent predictive factors for third-generation cephalosporin-resistant SBP, and third-generation cephalosporins should be used with caution in SBP patients with these features.

A Case of Monocular Gonococcal Conjunctivitis in an Adult Male / 계명의대학술지

Gonococcal conjunctivitis is rare in adults and, if not treated properly, can cause corneal perforation. Gonococcal conjunctivitis typically presents with a severe mucopurulent discharge, similar to that associated with viral conjunctivitis. Here, we describe a case of monocular gonococcal conjunctivitis, including its clinical characteristics and slit-lamp images, which was initially misdiagnosed as epidemic conjunctivitis. A 20-year-old man was referred to our hospital with no improvement in monocular infection and purulent ocular discharge after 2-wk treatment using antibiotic and 0.1% fluorometholone eye drops at the local ophthalmic clinic. Initially, 0.5% loteprednol eye drops were used since we suspected viral conjunctivitis. Following this treatment, conjunctival infection worsened and a yellow-white ocular discharge covered the conjunctiva and cornea surface. Additional history taking revealed that the patient had sexual contact with a prostitute 1 wk prior to symptom presentation and, after the encounter, he took antibiotics for genital discharge at the local urology clinic, but self-discontinued treatment. A Gram staining showed gram-negative diplococci and culture of collected ocular discharge from the palpebral conjunctiva revealed growth of Neisseria gonorrhoeae, confirming gonococcal conjunctivitis. Following this, the patient was systemically treated with 3rd generation cephalosporin antibiotics. After 3-d treatment, conjunctival infection and purulent ocular discharge had significantly improved. When clinical symptoms are aggravated following steroid eye drop treatment for suspected monocular viral conjunctivitis, gonococcal conjunctivitis must be considered as a differential diagnosis

Salicylic Acid Reduces OmpF Expression, Rendering Salmonella enterica Serovar Typhimurium More Resistant to Cephalosporin Antibiotics / 전남의대학술지

Salmonella enterica serovar Typhimurium is one of the most important bacterial pathogens causing diarrhea. The resistance of S. typhimurium to antimicrobial agents, which has recently been isolated from patients, is causing serious problems. We investigated the effects of salicylic acid (Sal) and acetyl salicylate (AcSal) on the susceptibility of S. typhimurium to cephalosporin antibiotics, which are known to increase resistance to cephalosporin and quinolone antibiotics. The MIC of cephalosporin antibiotics was higher than that of the media without Sal. The rate of accumulation of ethidium bromide (EtBr) in the bacteria by the outer membrane protein (Omp) was not different from that of the bacteria cultured in the medium containing Sal. However, Carbonyl cyanide-m-chlorophenylhydrazone (CCCP), an inhibitor of bacterial efflux pumps, significantly reduced the rate of accumulation of EtBr in bacteria cultured on Sal containing medium. In the medium containing CCCP, the MIC of the antimicrobial agent tended to decrease as compared with the control. In addition, the MIC of the bacteria treated with CCCP and Sal was higher than that of the antimicrobial agent against the CCCP treated experimental bacteria. These results suggest that Sal decreases the expression of OmpF in the Omp of S. typhimurium and reduces the permeability of cephalosporin antibiotics to bacteria, which may induce tolerance to cephalosporin antibiotics.

Research progress on status and mechanism of low sensitivity or resistance of Neisseria gonorrhoeae to cephalosporin / 中华全科医师杂志

Cephalosporin is still the first-line drug chosen for the treatment of gonorrhea, although it is likely to develop resistance to Neisseria gonorrhoeae. Recently, the resistance or low sensitivity of cephalosporin to Neisseria gonorrhoeae have been reported at home and abroad. The studies of resistance mechanism to Neisseria gonorrhoeae are particularly important. The resistance mechanism is mainly lied in three aspects. The first is the changes in antibiotic target sites, for example, the changes in penicillin-binding proteins would affect the binding of antibiotics to Neisseria gonorrhoeae; the second is the changes in bacterial cell membrane porin which effects drugs influxing; the third is the changes in efflux system which enhances the bacterial efflux capacity. To study and explore the mechanism of Neisseria gonorrhoeae resistance is of great importance for the prevention and treatment of gonorrhea.

Radiolytic studies of cefozopran hydrochloride in the solid state

Background: The radiation sterilization is one of the best methods for sterilizing vulnerable degradation drugs like cefozopran hydrochloride. Results: Chemical stability of radiosterylized cefozopran hydrochloride, was confirmed by spectrophotometric and chromatographic methods. EPR studies showed that radiation has created some radical defects whose concentration was no more than several dozen ppm. The antibacterial activity of cefozopran hydrochloride irradiated with a dose of 25 kGy was unaltered for Gram-positive bacteria but changed for two Gram-negative strains. The radiation sterilized cefozopran hydrochloride was not in vitro cytotoxic against human CCD39Lu normal lung fibroblast cell line. Conclusions: Cefozopran hydrochloride in solid state is not resistant to radiation sterilization and this method cannot be used for sterilization of this compound.

Clinical comparative study on azithromycin and ceftazidime in treatment of children with refractory mycoplasma pneumoniae pneumonia / 药物评价研究

Objective To investigate the effect of azithromycin and cefiazidime on serum lactate dehydrogenase (LDH) in children with refractory mycoplasma pneumoniae pneumonia.Methods From January 2014 to January 2017,120 children with refractory mycoplasma pneumoniae pneumonia in Women and Infants Hospital of Zhengzhou were selected as research object,all the cases were equally divided into observation group and control group with 60 cases in each group according to the random draw envelope principle,the observation group was given azithromycin adjuvant treatment,the control group was given cephalosporin adjuvant therapy,two groups were treated for 14 d.Results The total effective rates of observation group and control group were 98.3％ and 86.7％,respectively,the total effective rate of observation group was significantly higher than that of control group,the difference was statistically significant (P ＜ 0.05).The serum levels of LDH in observation group and control.group after treatment were (143.22±26.29) and (245.10 ± 30.91) U/L that were significantly lower than those before treatment of (445.20 ± 35.10) and (438.10 ± 56.11) U/L (P ＜ 0.05),and the serum level of LDH in observation group after treatment was significantly lower than that of the control group (P ＜ 0.05).The incidence of adverse reactions such as rash,gastrointestinal reaction,pain,fever and other adverse reactions in the observation group was 11.7％,which was 10.0％ in the control group.Comparison between the two groups had not significant difference (P ＜ 0.05).Conclusion Compared with cephalosporins,azithromycin in the treatment of refractory mycoplasma pneumoniae pneumonia in children can improve the therapeutic effect,and does not increase the incidence of adverse reactions,the mechanism may be related to the decrease of the content of serum LDH.

Nodular Vasculitis Associated with Cefazolin / 대한피부과학회지

No abstract available.

Clinical Significance of Extended-spectrum β-lactamase-producing Bacteria in First Pediatric Febrile Urinary Tract Infections and Differences between Age Groups

PURPOSE: Extended-spectrum β-lactamase-producing bacteria-induced urinary tract infections are increasing and require more potent antibiotics such as carbapenems. We evaluated the clinical significance of extended-spectrum β-lactamase urinary tract infection in children younger than 5 years to select proper antibiotics and determine prognostic factors. Differences were compared between age groups. METHODS: We retrospectively studied 288 patients with their first febrile urinary tract infection when they were younger than 5 years. Patients were divided into extended-spectrum β-lactamase-positive and extended-spectrum β-lactamase-negative urinary tract infection groups. Clinical characteristics and outcomes were compared between the groups; an infant group was separately analyzed (onset age younger than 3 months). RESULTS: Extended-spectrum β-lactamase urinary tract infection occurred in 11% patients who had more frequent previous hospitalization (P=0.02) and higher recurrence rate (P=0.045). During the antimicrobial susceptibility test, the extendedspectrum β-lactamase-positive urinary tract infection group showed resistance to third-generation cephalosporins; however, 98% patients responded clinically. In the infant group, extended-spectrum β-lactamase-positive urinary tract infection occurred in 13% patients and was associated with a longer pre-onset hospitalization history (P=0.002), higher C-reactive protein level (P=0.04), and higher recurrence rate (P=0.02) than that in the older group. CONCLUSION: Extended-spectrum β-lactamase urinary tract infection requires more attention because of its higher recurrence rate. The antimicrobial susceptibility test demonstrated resistance to third-generation cephalosporins, but they can be used as first-line empirical antibiotics because of their high clinical response rate. Aminoglycosides can be second-line antibiotics before starting carbapenems when third-generation cephalosporins do not show bactericidal effects for extended-spectrum β-lactamase urinary tract infection.

Clinical Significance of Extended-spectrum β-lactamase-producing Bacteria in First Pediatric Febrile Urinary Tract Infections and Differences between Age Groups

PURPOSE: Extended-spectrum β-lactamase-producing bacteria-induced urinary tract infections are increasing and require more potent antibiotics such as carbapenems. We evaluated the clinical significance of extended-spectrum β-lactamase urinary tract infection in children younger than 5 years to select proper antibiotics and determine prognostic factors. Differences were compared between age groups. METHODS: We retrospectively studied 288 patients with their first febrile urinary tract infection when they were younger than 5 years. Patients were divided into extended-spectrum β-lactamase-positive and extended-spectrum β-lactamase-negative urinary tract infection groups. Clinical characteristics and outcomes were compared between the groups; an infant group was separately analyzed (onset age younger than 3 months). RESULTS: Extended-spectrum β-lactamase urinary tract infection occurred in 11% patients who had more frequent previous hospitalization (P=0.02) and higher recurrence rate (P=0.045). During the antimicrobial susceptibility test, the extendedspectrum β-lactamase-positive urinary tract infection group showed resistance to third-generation cephalosporins; however, 98% patients responded clinically. In the infant group, extended-spectrum β-lactamase-positive urinary tract infection occurred in 13% patients and was associated with a longer pre-onset hospitalization history (P=0.002), higher C-reactive protein level (P=0.04), and higher recurrence rate (P=0.02) than that in the older group. CONCLUSION: Extended-spectrum β-lactamase urinary tract infection requires more attention because of its higher recurrence rate. The antimicrobial susceptibility test demonstrated resistance to third-generation cephalosporins, but they can be used as first-line empirical antibiotics because of their high clinical response rate. Aminoglycosides can be second-line antibiotics before starting carbapenems when third-generation cephalosporins do not show bactericidal effects for extended-spectrum β-lactamase urinary tract infection.

Impact of Revised Broad-Spectrum Cephalosporin Clinical and Laboratory Standards Institute Breakpoints on Susceptibility in Enterobacteriaceae producing AmpC β-Lactamase

We evaluated the impact of revised Clinical and Laboratory Standards Institute (CLSI) breakpoints for broad-spectrum cephalosporins (BSCs) on the susceptibilities of 1,742 isolates of Enterobacter species, Serratia marcescens, Citrobacter freundii, and Morganella morganii. The 2011 CLSI criteria for cefotaxime and ceftazidime reduced the rates of susceptibility by 2.9% and 5.9%, respectively. The 2014 CLSI criteria for cefepime reduced the rate of susceptibility by 13.9%, and categorized 11.8% isolates as susceptible-dose dependent (SDD) for cefepime. Among 183 isolates with extended-spectrum ß-lactamase (ESBL) phenotype, implementation of the new criteria reduced the rates of susceptibility to cefotaxime, ceftazidime, and cefepime by 2.8%, 14.8%, and 53.6%, respectively. The proportion of ESBL phenotype among BSC-susceptible isolates was low (0.9% for cefotaxime, 3.0% for ceftazidime, and 3.3% for cefepime). In summary, implementation of new CLSI criteria led to little change in susceptibility to cefotaxime and ceftazidime but a substantial change in susceptibility to cefepime. The recognition of revised CLSI criteria for BSC and SDD will help clinicians to select the optimal antibiotic and dosing regimen.