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PubMed1989

The bacteriology of acute maxillary sinusitis.

Sinus secretions obtained by antral aspiration from 347 patients with acute maxillary sinusitis were examined bacteriologically. Special attention was paid to the method by which anaerobic bacteria could be recovered. On the total, 485 sinus secretion samples were examined, of these 336 were aspirates, 149 yields of injection-aspirations. Aerobic bacteria were cultured from 263 aspirates and from 100 injection-aspiration samples. Only anaerobes were recovered from 6 sinuses. Bacterial culture was negative in 115 sinuses (24%). The most common pathogens isolated were Haemophilus influenzae (50.5%), Streptococcus pneumoniae (18.5%), Streptococcus pyogenes (5%) and Branhamella catarrhalis (1.5%). A true anaerobic infection was considered to be present in only 7 sinuses (1.5%) indicating that anaerobes are not a significant cause of acute maxillary sinusitis. According to this study the most common pathogen in acute maxillary sinusitis in young adults is H. influenzae. From this follows that in such patients aminopenicillins may be a more appropriate choice than conventional penicillin in the antimicrobial treatment of acute maxillary sinusitis.

Adult↗
PubMed1997

Characterization of the canine type C enterotoxin produced by Staphylococcus intermedius pyoderma isolates.

The type C staphylococcal enterotoxins (SECs) are a group of highly conserved proteins with substantial antigenic cross-reactivity. Although Staphylococcus intermedius and coagulase-positive species of staphylococci are reported to produce SEC and other SEs, toxins produced by species other than Staphylococcus aureus have not been previously characterized. In this study we report the molecular, biological, and immunological properties of the canine SEC (SECcanine) expressed by pathogenic isolates of S. intermedius. The mature form of SECcanine has 239 amino acid residues and a pI of 7.0. Typical of the SEs, purified SECcanine induces an emetic response in monkeys and the proliferation of T cells in a Vbeta-dependent manner. Although SECcanine has >95% sequence identity to previously described SEC variants, its sequence is most related to SEC2 and SEC3. In contrast to the sequence similarity, the Vbeta profile induced by SECcanine is typical of that induced by SEC1. This result is likely explained by the conservation of a cysteine residue at position 26 in SECcanine; residues at this position have been previously shown to determine subtype-dependent differences in T-cell receptor interactions of other SEs. Overall, these results show that superantigen toxins produced by the multiple members of the genus Staphylococcus are highly conserved in respect to biological and structural properties. Further, the frequent association of SECcanine with pyoderma in dogs supports the notion that the toxins are important for staphylococcal survival and pathogenesis.

Alleles↗
PubMedDate not supplied

Clinical efficacy and tolerance of two new macrolides, clarithromycin and josamycin, in the treatment of patients with acute exacerbations of chronic bronchitis.

The efficacy and safety of oral 500 mg clarithromycin given twice daily and 500 mg josamycin given three times daily were compared for up to 14 days in the treatment of 103 out-patients with acute exacerbations of chronic bronchitis in an open, randomized study. The predominant pathogens isolated were Streptococcus pneumoniae, Haemophilus influenzae and Staphylococcus aureus. Clinical cures were experienced by 85% of the clarithromycin-treated patients, with an additional 10% showing improvement. In josamycin-treated patients, 76% of the patients experienced clinical cures and an additional 19% showed improvement. Eradication of the causative pathogen occurred in approximately 95% of the patients in both treatment groups. Adverse events, which all involved the gastro-intestinal tract and were mild, transient and probably related to therapy, were experienced by 5.8% and 7.8%, respectively, of the clarithromycin- and josamycin-treated patients. It is concluded that clarithromycin given twice daily is as effective as josamycin given three times daily.

Adolescent↗
PubMed1991

[Antibiotherapy of maternal-fetal infections].

The initial antibiotic therapy of neonatal infections must be aimed at Streptococcus B, E. coli and Listeria which are the most frequent responsible pathogens. It must be initiated promptly and be effective against a possible meningeal infection. The first-line therapy with amoxicillin, amikacin and cefotaxime, which in theory should cover all the micro-organisms involved, must be short and rapidly replaced by an antibiotic proved to be active against the isolated pathogen. If aminoglycosides are administered for a long time, serum level assays are recommended for optimal safety.

Anti-Bacterial Agents↗
PubMed1994

Microbiology of community-acquired bacterial pneumonia in persons with and at risk for human immunodeficiency virus type 1 infection. Implications for rational empiric antibiotic therapy.

BACKGROUND: Bacterial pneumonia is a very common cause of morbidity and mortality among persons with human immunodeficiency virus; however, the microbiologic characteristics (including antibiotic resistance) of bacterial pathogens causing community-acquired pneumonia in this population have not been well characterized or correlated with potentially predictive clinical presentation characteristics. METHODS: We conducted a retrospective cohort study of all adults known to have or to be at high risk for human immunodeficiency virus infection and hospitalized at San Francisco (Calif) General Hospital from May 1990 through April 1991, with a hospital discharge diagnosis of community-acquired bacterial pneumonia and for whom a medical records review confirmed that this diagnosis met a uniform case definition. RESULTS: Two hundred sixteen eligible patients had one or more hospital admissions meeting the case definition. One or more etiologic pathogens were definitively identified in 75% of cases, with Streptococcus pneumoniae, Haemophilus species, Staphylococcus aureus, and gram-negative bacilli most frequently identified. In patients who had a bacteriologic diagnosis made, 18.6%, 6.8%, and 4.3% had pneumonia caused by pathogens resistant to ampicillin sodium, cefuroxime sodium, or trimethoprim-sulfamethoxazole, respectively. One hundred percent of pathogens isolated were susceptible to ceftazidime. Anemia and use of antibacterial medication at the time of hospital admission were the only independent predictors of ampicillin and cefuroxime resistance. CONCLUSION: Nearly one fifth of human immunodeficiency virus-associated community-acquired bacterial pneumonias requiring hospitalization were caused by ampicillin-resistant pathogens, and presenting clinical characteristics did not consistently define a subset of patients at lower risk for resistance. In the absence of a diagnostic sputum Gram's stain and pending definitive microbiologic diagnosis, initial empiric therapy should be with a second- or third-generation cephalosporin or possibly trimethoprim-sulfamethoxazole.

AIDS-Related Opportunistic Infections↗
PubMed1983

Immune reactions in infective endocarditis. I. Clinical data and diagnostic relevance of antimyocardial antibodies.

Clinical data from 72 patients with infective endocarditis (41 with defined pathogen, 31 with no pathogen isolated) were analyzed with respect to the diagnostic relevance of immunologic parameters. In our patients from a rural area, no significant changes in the epidemiology and pathogenesis of infective endocarditis were observed. Antiendocardial and antisarcolemmal (ASA) antibodies were demonstrated in 60% to 100% of cases. Their frequency depended on the endocarditic pathogen and on the clinical course: in subacute or chronic endocarditis these antibodies were found regularly, in acute lethal cases their occurrence was diminished. Whereas antiendocardial antibodies are diagnostic markers of endocarditis, ASA and antimyolemmal antibodies in particular most likely indicate myocardial involvement in endocarditis. Only complement fixing antimyolemmal antibodies induced cytolysis of vital, adult, heterologous cardiac cells. Our data suggest that antibody-mediated cytolysis in vitro may also play a pathogenetic role in vivo.

Adult↗
PubMed1999

Evaluation of empiric vancomycin therapy in children with fever and neutropenia.

A retrospective evaluation was conducted to determine which children admitted for fever and neutropenia required empiric vancomycin therapy, and to develop a clinical pathway for appropriate treatment. Chart review identified 109 admissions of 36 pediatric oncology patients for fever and neutropenia, of which 88 were eligible for analysis. Blood cultures isolated 17 gram-positive organisms; coagulase-negative staphylococci and viridans group streptococci were cultured most frequently (82%). We concluded that previous high-dose cytarabine therapy, inflamed central access site, and hypotension or septic shock are possible indicators of febrile, neutropenic patients at high risk for gram-positive pathogen isolation. These predictors then were used to determine which children would receive empiric vancomycin therapy.

Adolescent↗
PubMedDate not supplied

[The use of the polymerase chain reaction method in studying the causative agents of diphtherial infection].

A method for identification of genomic polymorphism of strains belonging to different biovars Corynebacterium diphtheriae has been described. The method is based on the polymerase chain reaction (PCR) using universal inter-species oligonucleotide primer N 45. Using this method 17 strains of C. diphtheria, isolated in the western region of Ukraine during epidemic activity in 1992, were studied. The study has shown high similarity of PCR patterns of toxicogenic and non-toxicogenic strains of both mitis and gravis biovars. It is supposed that the method will be used in molecular epidemiology to identify new pathogenic isolates from different regions and countries.

Carrier State↗
PubMedDate not supplied

Candida glabrata, Candida krusei, non-albicans Candida spp., and other fungal organisms in a sixty-bed national cancer center in 1989-1993: no association with the use of fluconazole.

During the 5-year period 1989-1993, the incidence of Candida krusei, and other non-albicans Candida spp., was analyzed in a 60-bed cancer department. The frequency of C. krusei, before fluconazole was introduced into therapeutic protocols in 1990, was 16.5%, and after introduction of fluconazole into prophylaxis in acute leukemia in 1991, the incidence of C. krusei was 12.7%. After 3 years of using this drug in therapy and prophylaxis, the incidence of C. krusei in 1993 was 14.8%, what was lower than before this drug was introduced in our country. 97.6% of all isolated fungi were yeasts and only 2.4% were molds. Among yeasts, the most frequently isolated pathogen was Candida albicans with 64.3% in 1989 and 74.2% in 1993. The next was C. krusei with 21.2% in 1992 and 16.5% in 1989, but 14.8% in 1993, and Candida tropicalis and Candida glabrata with 9.03% in 1989 and 2.7% in 1993. Among the molds, Aspergillus spp. was the most frequently isolated genus. Analyzing the etiology of mycologically proven fungal infections confirmed by positive blood cultures or biopsies, C. albicans and Aspergillus spp. were the most common causative organisms.

Cancer Care Facilities↗
PubMed2007

Causes of nosocomial pneumonia and evaluation of risk factors in a university hospital in Turkey.

OBJECTIVE: To determine the incidence, risk factors, mortality rate, and organisms causing nosocomial pneumonia (NP). METHODS: We carried out this study in the Intensive Care Units (ICUs), General Medical and Surgical wards of Baskent University, Training and Research Hospital in Adana, Turkey, between November 2000 and August 2002. Patients were observed from the time of admission until 48 hours after discharge from the hospital. RESULTS: In this study, 618 (2.1%) nosocomial infections (NIs) were detected in 29778 patients. One hundred and fifteen of these infections were NP and investigated with surveillance prospectively. The most frequently isolated microorganisms in NP were methicillin-resistant Staphylococcus aureus (MRSA) 32.8%, Pseudomonas species 21.5%, methicillin-sensitive Staphylococcus aureus (MSSA) 10.2%, Klebsiella species (9.1%) and Acinetobacter species 5.9%, E. coli; 5.4% (10/186), Streptococcus species; 4.8% (9/186), Candida species; 4.8% (9/186), Enterobacter species; 2.7% (5/186) and the other bacteria; 2.7%. The predominant pathogens isolated in this study were MRSA (33.8%), Pseudomonas species (16.9%) and MSSA (16.9%) in early-onset pneumonias and MRSA (32.2%), Pseudomonas species (24.0%), and Klebsiella species (10.7%) in late-onset pneumonias. CONCLUSION: This study demonstrated that the possibility of developing NP, significantly increases with such risk factors as decreased level of consciousness, respiratory failure, mechanical ventilation and tracheostomy. Each center should know its patients' profile, the factors that increase the infection, the antibiotic resistance patterns of microorganisms, and the distribution of hospital infections in every department. Strategies to prevent both development of antibiotic resistance and spread of resistant organisms are necessary.

Cross Infection↗
PubMed1997

Detection system for Escherichia coli-specific virulence genes: absence of virulence determinants in B and C strains.

We describe a rational approach to simultaneously test Escherichia coli strains for the presence of known virulence genes in a reverse dot blot procedure. Specific segments of virulence genes of E. coli designed to have similar hybridization parameters were subcloned on plasmids and subsequently amplified by PCR as unlabeled probes in amounts sufficient to be bound to nylon membranes. Various pathogenic isolates and laboratory strains of E. coli were probed for the presence of virulence genes by labeling the genomic DNA of these strains with digoxigenin and then hybridizing them to the prepared nylon membranes. These hybridization results demonstrated that besides the E. coli K-12 safety strain derivatives, E. coli B and C strains are also devoid of genes encoding any of the investigated virulence factors. In contrast, pathogenic E. coli control strains, used to evaluate the method, showed typical hybridization patterns. The described probes and their easy application on a single filter were shown to provide a useful tool for the safety assessment of E. coli strains to be used as hosts in biotechnological processes. This approach might also be used for the identification and characterization of clinically significant E. coli isolates from human and animal species.

Bacterial Typing Techniques↗
PubMed1998

Colonization of dental plaque: a source of nosocomial infections in intensive care unit patients.

OBJECTIVE: To study the dental status and colonization of dental plaque by aerobic pathogens and their relation with nosocomial infections in intensive care unit (ICU) patients. DESIGN: A prospective study in a medical ICU of a university-affiliated hospital. PATIENTS: Consecutive patients admitted to the ICU during a 3-mo period. INTERVENTIONS: Dental status was assessed by the same investigator using a score adapted from the "Caries-Absent-Occluded" (CAO) index (referred to in the U.S. as DMFT [Decayed-Missing-Filled Teeth] index). The amount of dental plaque on premolars was assessed using a semiquantitative score. Quantitative cultures of dental plaque, nasal secretions, tracheal aspirates, and urine were done at admission (day 0) and every fifth day until death or discharge. An additional study was done in eight patients to serially compare dental plaque, salivary, and tracheal aspirate cultures during a 2-wk period. MEASUREMENTS AND MAIN RESULTS: Fifty-seven patients were included in the main study. Due to the variability in their ICU stay, 29 patients could be examined on day 0 only (group A), 15 patients on days 0 and 5 (group B), and 13 patients on days 0, 5, and 10 (group C). The mean dental CAO score was 16 +/- 8 and did not change during the ICU stay. The dental plaque score was < or =1 in 70% of patients on day 0; > or =2 in 50% of patients on day 5; and > or =2 in 90% of patients on day 10. Dental plaque cultures were positive at 10(3) colony-forming units/mL for aerobic pathogens in 23% of patients on day 0; 39% of patients on day 5; and 46% of patients on day 10. In groups B and C, mean dental plaque score and frequency of plaque colonization increased from days 0 to 5 and from days 5 to 10. A high bacterial concordance was found between dental plaque and tracheal aspirate cultures, and in the additional study, between salivary and dental plaque cultures. Twenty-one patients developed a nosocomial infection in the ICU. Dental plaque colonization on days 0 and 5 was significantly associated with the occurrence of nosocomial pneumonia and bacteremia (sensitivity 0.77; specificity 0.96; positive predictive value 0.87; negative predictive value 0.91; relative risk 9.6). In six cases of nosocomial infection, the pathogen isolated from dental plaque was the first identified source of nosocomial infection. CONCLUSIONS: The amount of dental plaque increased during the ICU stay. Colonization of dental plaque was either present on admission or acquired in 40% of patients. A positive dental plaque culture was significantly associated with subsequent nosocomial infections. Dental plaque colonization by aerobic pathogens might be a specific source of nosocomial infection in ICU patients.

Adult↗
PubMed2003

Corynebacterium nigricans sp. nov.: proposed name for a black-pigmented Corynebacterium species recovered from the human female urogenital tract.

Six independent isolates of an unusual black-pigmented Corynebacterium species (strains CN-1, CN-2, CN-3415, W70124, 91-0032, and 92-0360) were recovered from the human female urogenital tract. Four of the six source patients had complications of pregnancy, including spontaneous abortion, preterm labor, and low amniotic fluid volume at the time of the pathogen isolation. One isolate was recovered from a vaginal ulcer. All six strains yielded black-pigmented colonies on sheep blood agar, chocolate agar, and colistin-nalidixic acid agar after 24 to 48 h of incubation at 35 degrees C. The dry, adherent colonies pitted the agar surface. The cells were coccobacillary to rod-shaped, catalase positive, nonmotile, and nonlipophilic. Only five of six isolates were available for characterization. Biochemical and chemotaxonomic studies revealed that the strains belong to the genus Corynebacterium but differ from known corynebacterial species. Comparative 16S rRNA gene sequence analysis showed that the strains are closely related and form a new subline within the genus Corynebacterium. We propose the name Corynebacterium nigricans sp. nov. for this group of coryneforms. The type strain of Corynebacterium nigricans is CN-1. It is deposited in the American Type Culture Collection (assigned strain number ATCC 700975) and in the Institute Pasteur collection (assigned strain number CIP 107346).

Adult↗
PubMed2002

The efficacy and safety of oral pharmacokinetically enhanced amoxycillin-clavulanate 2000/125 mg, twice daily, versus oral amoxycillin-clavulanate 1000/125 mg, three times daily, for the treatment of bacterial community-acquired pneumonia in adults.

This double-blind, double-dummy, parallel-group study was designed to show that a pharmacokinetically enhanced formulation of oral amoxycillin-clavulanate (16:1, 2000/125 mg), twice daily, is at least as effective clinically and microbiologically as oral amoxycillin-clavulanate 1000/125 mg, three times daily, in the 10 day treatment of community-acquired pneumonia (CAP) in adults. The pharmacokinetically enhanced formulation is designed to provide higher serum concentrations of amoxycillin for a longer period than standard dosing to achieve coverage of Streptococcus pneumoniae isolates with amoxycillin-clavulanic acid minimum inhibitory concentrations (MICs) up to and including 4 mg/l. A total of 344 patients with CAP from 77 centres received amoxycillin-clavulanate 2000/125 mg twice daily for 10 days (169 patients) or amoxycillin-clavulanate 1000/125 mg three times daily for 10 days (175 patients). The most common pathogen isolated was S. pneumoniae (52.3% of patients, amoxycillin-clavulanate 2000/125 mg group; 46.8% of patients, amoxycillin-clavulanate 1000/125 mg group). In the clinical per-protocol (PP) population at test of cure (days 18-39), the clinical success rate in the amoxycillin-clavulanate 2000/125 mg group was at least as good as in the amoxycillin-clavulanate 1000/125 mg group (91.5 and 93.0%, respectively; 95% CI, -8.3, 5.4). The radiological and bacteriological success rates at test of cure for the PP populations were 92.4 and 90.6% in the amoxycillin-clavulanate 2000/125 mg group and 93.9 and 84.4% in the amoxycillin-clavulanate 1000/125 mg group, respectively. The clinical, bacteriological and radiological success rates at the end of therapy (days 11-17) for the PP populations were all over 85%. Both regimens were well tolerated, with no differences in adverse events between the groups. Amoxycillin-clavulanate 2000/125 mg, twice daily, is well tolerated and at least as effective clinically as amoxycillin-clavulanate 1000/125 mg, three times daily, in patients with CAP and may also be appropriate for the treatment of infections due to S. pneumoniae strains with high-level penicillin resistance.

Adult↗
PubMed1982

[Pathogenic flora in hematology patients. Gram-negative germs and their in vitro sensitivity to antibiotics].

The results of microbiological research carried out on haematological patients admitted to the same ward are reported. The pathogenic flora observed consisted mainly of gram-negative germs (60%). Pseudomonas infections represented the most important problem because of their frequency and the consequent clinical problems. The in vitro sensitivity of 306 strains of gram-negative germs to 11 different antibiotics has been analysed. Amikacin proved to be easily the most effective antibiotic against isolated pathogens.

Amikacin↗
PubMed1991

Intravenous ciprofloxacin for the treatment of severe infections.

Intravenous ciprofloxacin at a daily dosage of 400 mg divided in two doses was administered to 19 patients with severe infections caused by ciprofloxacin-susceptible bacteria. These infections included: 11 surgical would infections, 5 soft tissue infections, 2 respiratory tract infections, 1 urinary tract infection. The offending pathogens were: 8 coagulase-negative staphylococci, 3 Staphylococcus aureus, 3 Pseudomonas aeruginosa, 2 Proteus spp., 1 Escherichia coli, 1 Branhamella catarrhalis, 1 Klebsiella ozenae and 1 Serratia liquefaciens. Overall, 17 of 19 infections (89%) showed a satisfactory clinical response to trial therapy (15 cures and 2 improvements). Microbiological eradication was observed in 17 out of 20 isolated pathogens. Emergence of resistance to ciprofloxacin occurred in 1 coagulase-negative Staphylococcus and was associated with clinical failure. No side effects were observed. We conclude that intravenous ciprofloxacin may represent efficacious and safe therapy of severe infections; however close microbiological monitoring seems to be necessary to evaluate the emergence of resistance during quinolone therapy.

Adult↗
PubMed2002

Antibiotic susceptibility of microorganisms at a general hospital in Lagos, Nigeria.

OBJECTIVE: To determine susceptibility patterns of microorganisms to antibiotics in a large general hospital in Lagos, Nigeria. METHODS: Clinical samples received in the laboratory were processed according to standard methods. Susceptibility to antibiotics was done using a disk diffusion technique. RESULTS: Five hundred and fifty-one samples from urine, wound, reproductive tract and other body fluids were analysed. The most frequently isolated pathogens (n=586) were Staphylococcus aureus, Escherichia coli and Klebsiella pneumoniae. Most of the organisms were sensitive to ciprofloxacin, perfloxacin, cefuroxime, ceftriaxone and azithromycin but were resistant to ampicillin, cotrimoxazole and penicillin. Pseudomonas aeruginosa was multi-resistant. The susceptibility pattern obtained at this hospital is similar to what obtains in teaching hospitals in Nigeria. CONCLUSION: Microorganisms isolated at this hospital are more sensitive to newer antibiotics.

Adult↗
PubMed2003

Relationships between patient- and institution-specific variables and decreased antimicrobial susceptibility of Gram-negative pathogens.

The identification of patients infected with antibiotic-resistant strains of bacteria for inclusion in clinical trials remains a serious challenge for the future development of agents for use against such infections. To identify patient- and institution-specific factors predictive of reduced susceptibility of Enterobacter species, Pseudomonas aeruginosa, and Klebsiella pneumoniae to cefepime, ciprofloxacin, and piperacillin-tazobactam, 5 years (1997-2001) of North American surveillance data were analyzed. The relationship between minimum inhibitory concentration (MIC) values for each organism-agent pair and patient- and institution-specific variables was analyzed using multivariable general linear modeling. The variables most commonly associated with decreases in susceptibility were duration of hospital stay before pathogen isolation, hospital size, primary diagnosis, and medical service. Combinations of these variables were associated with increases in observed MIC90 values of as much as 16-32-fold. Our findings demonstrate a relationship between MIC and certain patient- and institution-specific variables. Such data should be considered in the design of clinical trials directed at the study of resistant pathogens.

Anti-Bacterial Agents↗