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[E.coli from urinary tract infections and acute pyelonephritis of children: 1% of strains are resistant to a subset of third generation cephalosporins].

E. coli remains the most often isolated pathogen in community urinary tract infections in children. We reported a retrospective study of antibiotic susceptibility of 506 E. coli strains isolated from urine. We found that 53% of the strains were resistant to amoxicilline and 22% to cotrimoxazole. The frequency of resistance to amoxicillin-clavulanic acid was of 7%, 40% of the strains were just intermediary and 53% were sensitive. Only five strains (1%) were resistant to ceftazidime: two mechanisms of resistance, hyperproduction of TEM betalactamase (3 cases) and cephalosporinase (2 cases), were suggested. This study illustrates the necessity of constant monitoring of bacterial resistance to adapt antibiotherapeutic guidelines to local evolution.

Acute Disease↗

Cefdinir versus cefaclor in the treatment of uncomplicated urinary tract infection.

OBJECTIVE: This multicenter, double-blind, randomized, parallel-group study was conducted in Europe, South Africa, and Australia to compare the clinical and microbiologic efficacy and the tolerability of a cephalosporin antibiotic, cefdinir, with those of cefaclor in the treatment of uncomplicated urinary tract infection. METHODS: Patients were randomized in a 1:1 ratio to 5 days of treatment with either cefdinir 100 mg BID or cefaclor 250 mg TID. RESULTS: A total of 661 patients were randomized to treatment. They were 90% female, with a median age of 44 years. There were no clinically important differences between groups in terms of demographic characteristics or symptoms on admission. The most frequently isolated pathogens in admission urine cultures were Escherichia coli (383 patients), Proteus mirabilis (20 patients), Staphylococcus saprophyticus (14 patients), and Klebsiella pneumoniae (9 patients). Of the admission pathogens with documented susceptibility results, significantly more were resistant to cefaclor (6.7%) than to cefdinir (3.7%; P < 0.003). Significantly more admission isolates of E. coli were resistant to cefaclor (5.1%) than to cefdinir (2.0%; P < 0.007). A total of 383 patients were assessable for efficacy, 196 in the cefdinir group and 187 in the cefaclor group. Clinical cure rates and microbiologic response rates for cefdinir and cefaclor were statistically equivalent at 5 to 9 days posttherapy (test-of-cure visit), using a 95% CI approach. The rate of treatment-related adverse events was higher in cefdinir-treated patients (20.2%) than in cefaclor-treated patients (13.0%; P = 0.025), mainly due to the greater frequency of diarrhea in the former group. However, only 4 patients (1.2%) discontinued cefdinir treatment due to diarrhea. CONCLUSION: Empiric therapy with cefdinir appears to be a reasonable choice for patients with uncomplicated urinary tract infection in whom cephalosporin treatment is indicated.

Adolescent↗

[Epidemiology of Staphylococcus aureus nosocomial infections in a high-risk neonatal unit].

Nosocomial infections are a significant cause of morbidity and mortality throughout the world. In developing countries it is difficult to carry out effective surveillance and control programs for this type of infection because of the cost in both human and material resources. These considerations prompted us to perform a prospective study to determine the epidemiologic and microbiologic characteristics of nosocomial infections due to Staphylococcus aureus in the High-risk Neonatal Unit (HRNU) of the Instituto Autónomo Hospital Universitario de Los Andes (IAHULA), during the period of November 1997 to October 1998. Among a total of 120 microorganisms, 24 (20%) strains of Staphylococcus aureus were isolated; 47% were recovered from blood and 33% from conjunctive samples. Among the cases of conjunctivitis, S. aureus was the only pathogen isolated in 42%. Twenty of the 24 Staphylococcus aureus strains (83%) were methicillin-resistant (MRSA). According to their resistance profiles, we established 12 groups of strains from neonates with nosocomial infections and 1 group of strains from the two carriers among the healthcare personnel detected by microbiological screening. The MeRGmR pattern was the most frequent. Plasmid analysis disclosed two profiles, each having a plasmid molecular weight over 23.130 bp. The MRSA strains isolated from the neonates and those isolated from the carriers showed the same plasmid profile. This suggests that the healthcare personnel may have acted as reservoirs of the MRSA strains found in neonates with nosocomial infection.

Cross Infection↗

Comparison of aztreonam and tobramycin in the treatment of lower respiratory tract infections caused by gram-negative bacilli.

A comparison of aztreonam and tobramycin was carried out in 49 hospitalized patients with lower respiratory tract infections caused by gram-negative bacilli. Patients were randomly assigned to the treatment drug. Clindamycin was given concomitantly until the pathogen was identified and the presence of a gram-positive microorganism was ruled out. Samples of sputum were obtained for culture from the lung parenchyma by deep expectoration or transtracheal aspiration. A pathogen was defined as an organism that showed heavy growth and predominated in the culture. Pseudomonas aeruginosa was the most frequently isolated pathogen, followed by Haemophilus influenzae and Proteus mirabilis. A variety of less common pathogens were represented. Thirty-five patients were treated with intravenous aztreonam (1-2 g every 8 hr) and 14 with intravenous tobramycin (3-5 mg/kg per day) until they were afebrile and sputum cultures had been free of the pathogen for 48 hr. The minimum duration of treatment was five days. In the aztreonam group, only two (5%) of the 37 gram-negative pathogens--one P. aeruginosa and one Escherichia coli--persisted. In the tobramycin group, seven (50%) of the 14 pathogens persisted. Clinical response paralleled microbiologic response. Adverse effects in both treatment groups were minor and transient. In this trial aztreonam was effective and safe for treatment of lower respiratory tract infections caused by P. aeruginosa and a variety of other gram-negative bacilli.

Aztreonam↗

An overview of nosocomial infections, including the role of the microbiology laboratory.

An estimated 2 million patients develop nosocomial infections in the United States annually. The increasing number of antimicrobial agent-resistant pathogens and high-risk patients in hospitals are challenges to progress in preventing and controlling these infections. While Escherichia coli and Staphylococcus aureus remain the most common pathogens isolated overall from nosocomial infections, coagulase-negative staphylococci (CoNS), organisms previously considered contaminants in most cultures, are now the predominant pathogens in bloodstream infections. The growing number of antimicrobial agent-resistant organisms is troublesome, particularly vancomycin-resistant CoNS and Enterococcus spp. and Pseudomonas aeruginosa resistant to imipenem. The active involvement and cooperation of the microbiology laboratory are important to the infection control program, particularly in surveillance and the use of laboratory services for epidemiologic purposes. Surveillance is used to identify possible infection problems, monitor infection trends, and assess the quality of care in the hospital. It requires high-quality laboratory data that are timely and easily accessible.

Bacterial Infections↗

The infectivity of sarcoid clinical material and its bacterial content inoculated in CBA mice.

BACKGROUND: Sarcoidosis is a multisystemic disorder that is currently viewed as the consequence of chronic immunological response associating genetic susceptibility and specific environmental or transmissible agents. Relevant evidence, although conflicting, justifies a concern about the involvement of specific pathogens to disease causation. In this study we assessed the infectivity of sarcoid clinical material, and of the pathogens found in it, to normal CBA mice used as a model of an immuno-competent host. MATERIALS AND METHODS: One hundred and eleven mice were inoculated into their footpads with fresh, filtered, and autoclaved, sputum and bronchoalveolar lavage homogenates, collected from patients with sarcoidosis, and with the mycobacterial and propionibacterial pathogens isolated from this material. RESULTS: The total number of positive reactors of the animals that received raw clinical material and the pathogens it contained was statistically significant compared to those of the control groups. However, the number of affected mice per group was in most cases less than 50% and inflammation was almost always mild and local. CONCLUSION: Based on the evidence provided by inoculation of normal CBA mice, some of the material under study, although of mild potency, can be infectious to an immuno-competent host.

Animals↗

[Pulmonary and tonsillar distribution of ceftriaxone and cefonicid and the resultant bactericidal activity of the organ].

The therapeutic efficacy of Ceftriaxone and Cefonicid 1 g I.M. single-dose against S. Pneumoniae, H. Influenzae and K. Pneumoniae in tonsil and lung infections was studied using bactericidal quotient (BQ). Samples of lung tissue and serum were obtained from two groups of surgical patients, treated with Ceftriaxone or Cefonicid 1 g I.M., 2-8-16 and 24 hours before surgery. From two other groups of 10 surgical patients, treated as above, samples of tonsil tissue and serum were obtained. In lung tissue the higher levels of Ceftriaxone and Cefonicid appeared at the second hour (11.54 +/- 1.59 mcg/g and 11.4 +/- 2.49 mcg/g respectively); the lower values were observed at the 24th hour (2.18 +/- 0.47 mcg/g for Ceftriaxone and 0.64 +/- 0.21 mcg/g for Cefonicid). Higher Ceftriaxone and Cefonicid levels also appeared in tonsil tissue at the 2nd hour (11.12 +/- 2.42 mcg/g and 9.22 +/- 3.12 mcg/g respectively); the lower values were observed at the 24th hour (1.54 +/- 0.46 mcg/g for Ceftriaxone and 0.42 +/- 0.23 mcg/g for Cefonicid). BQ values were estimated using the ratio between the mean concentrations of Ceftriaxone and Cefonicid in tissue samples and the MBC mean values determined for the above mentioned pathogens, isolated in hospital. Ceftriaxone always showed BQ values greater than 1 during 24 hours versus levels observed for the three reported pathogens. Cefonicid showed BQ values greater than 1 during 24 hours against S. Pneumoniae and BQ values less than 1 for 6-8 hours against H. Influenzae and for 1-4 hours against K. Pneumoniae.

Adolescent↗

A Decade of Achievements and Future Directions in Global Antimicrobial Resistance Surveillance System in Korea (Kor-GLASS).

OBJECTIVES: To comprehensively evaluate the 10-year operational outcomes (2016-2025) Global Antimicrobial Resistance Surveillance System in Korea (Kor-GLASS), assess its public health significance for national stewardship and global surveillance, and propose strategies for future development. METHODS: The study described the operational framework of Kor-GLASS, including its strain collection, analysis, and quality control systems, based on surveillance data. It analyzed resistance trends among key bloodstream pathogen isolates collected from 2016 to 2024 and evaluated major achievements, including alignment with the World Health Organization (WHO)'s Global Antimicrobial Resistance Surveillance System (GLASS), integration with the Emerging Antimicrobial Resistance Reporting (EAR) system, and activities as a WHO Collaborating Centre. RESULTS: Kor-GLASS operates on a foundation of standardized, isolate-based surveillance supported by an independent quality management system that complies with WHO GLASS standards. In alignment with the strategic direction of WHO GLASS, the surveillance scope has progressively expanded in terms of catchment areas, target pathogens, specimen types, and antimicrobial panels. From 2016 to 2024, a total of 116,955 clinical isolates were collected and analyzed through the network of collection and analysis centers. This has enabled the continuous generation of nationally representative antimicrobial resistance (AMR) data from general hospitals. The accumulated surveillance data provide fundamental evidence for tracking long-term resistance trends and elucidating the molecular epidemiological characteristics of key pathogens. These outcomes are disseminated through the publication of the "National Antimicrobial Resistance Surveillance Annual Report" and data submissions to WHO GLASS and GLASS-EAR, thereby supporting both national and global AMR surveillance efforts. Furthermore, Kor-GLASS has strengthened international surveillance and One Health collaboration capacities through its designation and redesignation as a WHO Collaborating Centre for AMR Surveillance. CONCLUSIONS: Over the past decade, Kor-GLASS has served as the cornerstone of national antimicrobial resistance surveillance, providing evidence to inform policy and supporting global surveillance systems. Moving forward, Kor-GLASS is expected to evolve into a pivotal national AMR surveillance system through the introduction of whole-genome sequencing and stronger integration with national antimicrobial consumption surveillance.

Anti-bacterial agents↗

Pathogenicity of various isolates of Alcaligenes faecalis for broilers.

Day-old broilers or specific-pathogen-free chickens were inoculated intranasally with approximately 1 X 10(8) organisms of eight different field isolates of Alcaligenes faecalis. Major differences in the pathogenicity of isolates and their ability to colonize the trachea were found. Only two isolates (Wilson and Lockamy) produced mild clinical signs of respiratory disease ("snicking," dyspnea). The same two also colonized the respiratory tract, especially the trachea, in large numbers; they persisted for 31 days. Of the remaining six isolates, five were also able to colonize the respiratory tract but did so to a lesser degree and less persistently, without causing clinical signs. Only one isolate (CS) was incapable of becoming established in the respiratory tract of chicks after intranasal inoculation.

Alcaligenes↗

Antimicrobial activity of tigecycline against recent isolates of respiratory pathogens from Asian countries.

In vitro activities of tigecycline were compared with 15 other comparator agents against recent clinical isolates of respiratory pathogens (623 Streptococcus pneumoniae, 105 Staphylococcus aureus, 92 Klebsiella pneumoniae, and 84 Haemophilus influenzae isolates) collected from 11 Asian countries. All isolates of S. pneumoniae from Asian countries were susceptible to tigecycline regardless of penicillin susceptibility with MIC90 of <or=0.06 mg/L. Both methicillin-resistant and methicillin-susceptible S. aureus isolates were susceptible to tigecycline with very low MIC90 values (0.25 and 0.12 mg/L, respectively). Tigecycline was also active against K. pneumoniae (98.9% susceptible; MIC50, 1 mg/L; MIC90, 2 mg/L) including 10 extended-spectrum beta-lactamase-producing isolates and H. influenzae (100% susceptible; MIC50 and MIC90, 0.12 mg/L) from Korea. Data confirmed that tigecycline has an excellent in vitro activity against drug-resistant clinical isolates of respiratory pathogens from Asian countries.

Anti-Bacterial Agents↗

Microbiological agents associated with childhood diarrhoea in the dry zone of Sri Lanka.

Between March and July, 1987, faecal specimens from 371 diarrhoeal children reporting to four hospitals in the district of Kurunegala, Sri Lanka and from 121 controls with other diseases were investigated for enteric pathogens. All specimens were tested for Shigella spp, Salmonella spp and enteropathogenic Escherichia coli (EPEC). In addition, parasitic pathogens, heat labile enterotoxigenic Escherichia coli (ETEC LT), Campylobacter and rotavirus were sought among subsamples of the cases and controls. One or more pathogens were detected in the faecal specimens of 53.7% of the diarrhoeal children and 19.6% of the controls (P less than 0.001). Rotavirus was the most frequently identified pathogen. Cases (21.9%) were more likely to be positive for rotavirus than controls (6.5%) (p less than 0.05). Among children with diarrhoea the peak prevalence of rotavirus occurred in the 6-11 months age group. Shigella spp were the second most frequently isolated pathogens and the single most common cause of diarrhoea in children over two years of age. Again, cases (16.4%) were more likely to be infected than controls (1.7%) (p less than 0.001). Salmonella spp were isolated from 7.5% of diarrhoeal children and 3.3% of the controls (p greater than 0.10). Other pathogens had prevalence rates of less than 5%. Vomiting was associated with rotavirus diarrhoea (p less than 0.001), and fever with shigellosis (p = 0.02). In view of the different transmission routes and characteristics of the most important pathogens detected in this study it appears unlikely that a single environmental intervention can solve the public health problem posed by diarrhoeal diseases in Sri Lanka.

Acute Disease↗

Complete DNA sequence, comparative genomics, and prevalence of an IncHI2 plasmid occurring among extraintestinal pathogenic Escherichia coli isolates.

We have sequenced a large plasmid that occurs among avian pathogenic Escherichia coli isolates. This plasmid, pAPEC-O1-R, is a 241,387-bp IncHI2 plasmid which is cotransmissible via bacterial conjugation with a ColBM virulence plasmid, encodes resistance to eight antimicrobial agents, and appears to occur at low rates among extraintestinal E. coli isolates.

Animals↗

Effect of antifungal drugs on pathogenic Naegleria spp isolated from natural water sources.

UNLABELLED: Five of 16 strains of pathogenic Naegleria spp isolated from 350 natural water sources in Taling Chan District, Bangkok had similar molecular weights and zymogram patterns to those of Naegleria fowleri CDCVO 3081 and Thai strain. The in vitro effects of antifungal drugs (amphotericin B, ketoconazole, fluconazole and itraconazole) were tested at the following concentrations: amphotericin B 0.01-0.55 microg/ml, ketoconazole 0.01-0.3 microg/ml, fluconazole 0.75-3.5 mg/ml and itraconazole 4-12 mg/ml respectively. Aliquots (15,000 cells/ml) of the amoebae were placed in the cells of the microtiter plate and incubated at 37 degrees C. Amoebae from each treatment sample were exposed to one of the four antifungal drugs. Statistical analysis was done by dependent t-test. The sensitivity of the antifungal drugs (MIC50) was as follows: amphotericin B 0.03-0.035 microg/ml ketoconazole 0.05-0.15 microg/ml fluconazole 1.75 mg/ml and itraconazole 8-9 mg/ml respectively (p < 0.005). CONCLUSION: Amphotericin B and ketoconazole are more active against Naegleria fowleri in vitro. The results of the present study should be used as an in vitro screening test for drugs that have potential amebicidal activity.

Amphotericin B↗

Bacteroides fragilis adheres to laminin significantly stronger than Bacteroides thetaiotaomicron and other species of the genus.

The laminin binding properties of eight species of the genus Bacteroides were examined using latex particle agglutination assay. B. fragilis was found to bind strongly to laminin, whereas all other species tested showed no or only weak laminin adherence. The pronounced differences in laminin binding activity between B. fragilis on the one side and B. thetaiotaomicron and B. ovatus on the other were determined to be statistically significant (p < 0.001 and p < 0.01, respectively). With regard to the relevance of laminin adherence for bacterial pathogenicity and invasiveness, our results give a possible explanation for the well-known finding that B. fragilis is the most frequently isolated pathogen in anaerobic bacteremia.

Bacterial Adhesion↗

[The effective antibacterial spectrum of sulfacetamide].

Swabs of the anterior eye segment of 180 eyes (145 patients) taken in the time period between August 1, 1989 until August 30, 1989 were sent to an external, independent microbiological institute in order to verify in-vitro antibacterial properties of marketed sulfacetamide containing drugs. MIC test was performed with isolated pathogenic bacterial strains without knowledge of the underlying diagnosis. It was shown that sulfacetamide is able to inhibit the growth of all isolated strains. Depending on the type of bacteria concentrations of 0.006 up to 6.4% sodium sulfacetamide proved to be effective. Simultaneously, all patients were treated with sulfacetamide containing ointment and/or eye drops 4 times daily for maximum of 14 days. With swabs taken at intervals of 7 and 14 days no bacterial growth was detected.

Bacteria↗

Septic arthritis of the glenohumeral joint. A report of 11 cases and review of the literature.

Eleven cases (6 adults and 5 pediatrics) of shoulder septic arthritis are described, and the English literature from 1960 to 1997 reviewed, for a total of 168 cases. Shoulder septic arthritis is an uncommon and difficult diagnosis requiring a high index of suspicion and early evaluation of the affected shoulder by the clinician. The disease usually involves very young infants or elderly patients (65-75 years old). Associated medical conditions were identified in 60% of the patients and include systemic disorders such as liver diseases, alcoholism, and malignancies in 46%; preceding chronic arthritic disorders in 24%; and associated infectious focus in 13% of the patients. Associated infections were more prevalent in the pediatric population. Intravenous drug abuse appears not to constitute a major risk factor; it was identified in less than 5% of patients. All patients presented with acute shoulder ache or with exacerbation of existing chronic pain in joints previously damaged. Elevated body temperature (over 38 degrees C) appeared in 67% of the adult patients and in over 90% of the pediatric patients. Shoulder arthritis was frequently accompanied by an accelerated erythrocyte sedimentation rate that may rise above 100 mm/hr. Increased white blood cell count was found in approximately 40% of patients. The initial X-rays were frequently normal, while ultrasonography supported the diagnosis in some cases by demonstrating accumulation of fluid inside the joint space. Aspiration of synovial fluid from the affected glenohumeral joint was necessary to evaluate the offending pathogen. False-negative Gram stain appeared in approximately 90% of the patients, whereas synovial fluid cultures demonstrated the pathogen in 88% of patients. Blood cultures were positive in 50% of adult patients and 90% of pediatric patients. The most common isolated pathogen was Staphylococcus aureus, which accounted for 41% of infections. Gram-negative bacilli, which accounted for about 20% of infections, are more prevalent in the pediatric population, especially the neonates. Pyogenic shoulder arthritis should first be treated with intravenous antibiotics, effective at least against staphylococcal infections, until the organisms and sensitivities are identified. Duration of antibiotic therapy should be 3-6 weeks. Unfortunately, our experience in addition to the literature summary does not allow statistical analysis and firm conclusions concerning the best therapeutic approach. However, it appears that in the adult population an operative draining procedure is preferred, whereas in the pediatric population, a closed needle aspiration, if needed at all, is the optimal treatment. With prompt antibiotic therapy and drainage of the shoulder, the patient can be expected to improve clinically, with no serious long-term debilitating effects from the disease.

Aged↗

Microbiologic evaluation of frequent-replacement soft contact lenses.

PURPOSE: This article reports a microbiologic study of two kinds of monthly frequent-replacement daily wear soft contact lenses, with different amounts of water content, in asymptomatic contact lens wearers. METHOD: We studied 35 lenses of 18 patients who wear frequent-replacement soft contact lenses with a water content of 38% and 40 lenses of 20 patients using frequent-replacement contact lenses with a water content of 55%. The lenses worn by patients regularly for 1 month were removed from their eyes in a sterile manner on the 30th day and were studied microbiologically to isolate pathogenic agents. RESULTS: In the group of monthly frequent-replacement soft contact lenses with a water content of 38%, microorganisms were isolated at a rate of 91%; and in the group of monthly frequent-replacement soft contact lenses with a water content of 55%, microorganisms were isolated at a rate of 85%. When the two groups were compared, there was no statistically significant difference (P=0.31). Although coagulase-negative staphylococci, Corynebacterium spp, and gram-negative rods were detected in both groups, Staphylococcus aureus, non-hemolytic streptococci, Neisseriae spp, and Penicillium spp also were isolated in the group with the higher water content. CONCLUSION: Bacteria spreading from the environment or from skin flora to the eyes showed more diversity in the group of frequent-replacement soft contact lenses with a high water content. Additionally, Penicillium spp also was isolated in this group. Therefore scrupulous attention to daily lens care is crucial for people who wear frequent-replacement soft contact lenses.

Adolescent↗