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PubMed1990

Risk factors of nosocomial bacteremia associated with pulmonary artery catheters in a critical care unit.

An epidemiologic investigation at a community teaching hospital identified 17 cases of endemic primary nosocomial bacteremias associated with the use of pulmonary artery catheters (PACs). A matched-case control study was undertaken to identify risk factors associated with these bacteremias. Factors significantly associated with bacteremia were length of hospitalization; length of stay in the critical care unit; length of time the PAC introducer was left in place and used as an intravenous (IV) access device after PAC withdrawal; respiratory compromise; PAC site infection; prior infections at other sites; concomitant hyperalimentation; and number of IV piggyback administrations per day prior to onset of bacteremia. Pathogens isolated included coagulase-negative Staphylococcus species (55.6%), Staphylococcus aureus (22.2%), Candida albicans (14.8%), and enterococci (7.4%). These pathogens were generally resistant to antibiotics given before the development of bacteremia. Bacteremia was associated with significant mortality, a prolonged hospital stay, and increased hospital charges. This study identifies important risk factors to consider in formulating guidelines to prevent and control PAC-associated nosocomial infections.

Aged↗
PubMed1993

Nosocomial urinary tract infection: a microbiological study.

Nosocomial urinary tract infection (UTI) is an important cause of increased morbidity and mortality in hospitalised patients. The increasing use of broad spectrum antibiotics will result in changes in the microbiological and antibiotic sensitivity pattern of pathogens isolated from nosocomial UTI. We have endeavoured to study the bacteriological pattern of nosocomial UTI and the antibiotic sensitivity patterns of the pathogens concerned. Over a period of one year, a total of 541 patients with 656 episodes of nosocomial UTI were studied. A total of 748 organisms were isolated. The two main complicating factors in nosocomial UTI were urogenital instrumentation (70.4%) and diabetes mellitus (24.2%). Klebsiella species (spp) was the predominant organism isolated (25.0%) and was significantly associated with age and diabetes mellitus. Klebsiella spp in nosocomial UTI showed an overall increase in resistance to antibiotics and multiple antibiotic resistant strains were not uncommon. Escherichia coli was isolated in 17.7% of cases. Streptococcus faecalis was isolated in 10.6% of cases and was significantly associated with instrumentation. Pseudomonas spp was isolated in 8.6% of cases and was generally sensitive to ceftazidime and amikacin. It was associated with systemic malignancies and the use of immunosuppressants.

Adolescent↗
PubMed2004

[Microbiology of acute exacerbation chronic sinusitis in adults].

The bacterial flora taken by sinus puncture from 115 patients with uni and bilateral acute exacerbation of chronic maxillary sinusitis was analyzed. Germ-free culture was obtained in 49 cases (40%) and in 69 cases (60%) bacteria were isolated from all sinus aspirates. Microbiological evaluation shows, that in majority of cases (90%) of acute exacerbation of chronic sinusitis there were pathogenic bacteria namely aerobic and anaerobic. The most frequent pathogens isolated from the aspirates were; Staphylococcus aureus, Haemophilus influenzae, Escherichia coli, Streptococcus pneumoniae, Staphylococcus hominis, Propionibacterium acnes i Candida albicans. The culture analysis proves that one or more pathogens can be the etiological factor. In the majority of cases (64%) the sinusitis is caused by monoculture.

Acute Disease↗
PubMed2001

Bacteraemia and mortality among adult medical admissions in Malawi--predominance of non-typhi salmonellae and Streptococcus pneumoniae.

OBJECTIVES: The high seroprevalence of HIV in Malawi might be expected to alter the pattern of pathogens isolated from bacteraemic patients. We aimed to describe the frequency and seasonal pattern of bacterial isolates from blood, their antibiotic susceptibility, and patient outcome, in order to provide data on which to base empirical antibiotic therapy and further studies of pathogenesis. METHODS: Over a 12-month period, blood cultures were taken from all febrile adult medical admissions to Queen Elizabeth Central Hospital, Blantyre. RESULTS: A total of 2789 out of 9298 adult general medical admissions had blood culture performed, of whom 449 (16.1%) grew significant pathogens. Non-typhi salmonellae (NTS) (37%) and Streptococcus pneumoniae (30%) were the two commonest isolates. Mortality was 18% among general medical admissions and 38% among bacteraemic patients. Mortality for individual pathogens was: NTS 33%; S. pneumoniae 36%; Escherichia coli 54%; Klebsiella spp. 58%; Neisseria meningitidis 44%; Salmonella typhi 17%. Despite an overwhelming association between the major pathogens and HIV infection (95% of S. pneumoniae cases and 92% of NTS cases were seropositive for HIV), a seasonal pattern was preserved. Streptococcus pneumoniae was more frequently isolated in the cold dry months, while STM isolates increased following a rise in temperature. A case of bacteraemia with Vibrio cholerae (serotype 01) was detected during a cholera outbreak in the rainy season. Although S. pneumoniae isolates were relatively susceptible to penicillin (88%) and chloramphenicol (74%), S. typhimurium isolates were fully susceptible only to chloramphenicol. CONCLUSIONS: This large study confirms the dominance of NTS and S. pneumoniae in bacteraemia in an area affected by HIV-1 and allows comparison of mortality by individual pathogens. It demonstrates a preserved seasonal pattern of bacteraemia for these major pathogens, despite an overwhelming association with HIV infection.

Adolescent↗
PubMed1997

Natural history and spectrum of disease in adults with HIV/AIDS in Africa.

Progression from seroconversion to the development of AIDS in Africa may be shorter than in industrialized countries, but there are insufficient data to be certain. Although the data are not always directly comparable, survival after an AIDS diagnosis appears to be substantially shorter in African countries and this may be partly because of later diagnosis of AIDS in Africa, but may also be because of environmental factors such as increased exposure to pathogens of high virulence and lack of access to care. Tuberculosis and bacterial infections are the most important causes of morbidity and mortality among hospitalized patients. Bacteraemia is frequent, particularly due to non-typhoid salmonellae and S. pneumoniae. Cryptosporidia and I. belli are the most frequently isolated pathogens in patients with diarrhoea; non-typhoid salmonellae and Shigella species are also commonly isolated when stool cultures are performed. Cerebral toxoplasmosis, and meningitis due to Cryptococcus, tuberculosis and bacterial pathogens are the most frequent neurological infections and cognitive changes are frequently identified when specifically looked for. Infections with atypical mycobacteria and Pneumocystis carinii are rare, as is CMV retinitis. In women, HIV infection is associated with cervical human papillomavirus and with SIL, although there is currently no evidence for an association with invasive cervical cancer. Individuals infected with HIV-2 progress to AIDS and to death more slowly than those infected with HIV-1, but seem to experience the same spectrum of opportunistic disease when they reach the stage of advanced disease. The limited data available suggest that HIV-infected individuals in Africa develop opportunistic disease at broadly the same level of immunosuppression as do individuals in industrialized countries, but death occurs at a higher range of CD4 counts, although still in the range consistent with advanced disease. Data are still lacking concerning the aetiology of common clinical presentations of HIV disease and the relative frequencies of specific opportunistic diseases in different regions, particularly from southern Africa. Tuberculosis is the single most important HIV-related opportunistic infection in African countries, but diagnosis, particularly of extrapulmonary disease, remains difficult. The lack of laboratory facilities makes the diagnosis of bacterial infections difficult in many parts of the continent and, since this situation is unlikely to change in the near future, clinical algorithms for syndromic management need to be evaluated. More information is needed about gynaecological disease in HIV-infected women. The most important research questions concern the development and evaluation of cost-effective regimes for prophylaxis and treatment of opportunistic disease in order to prolong healthy life in HIV-infected individuals.

AIDS-Related Opportunistic Infections↗
PubMed1988

Use of microbiology reports by physicians in prescribing antimicrobial agents.

The purpose of this study was to examine the use of microbiologic reports by physicians in prescribing antimicrobial agents in a community hospital setting. Patients were identified by daily review of all blood, urine, and sputum cultures that grew pathogen(s) during a 7-week period. Appropriateness of antibiotic therapy was based on results of antibiotic susceptibility testing of isolated pathogen(s). The physician response to culture results was evaluated on changes made in antimicrobial therapy. Seventy-one patients with 73 cultures (infections) were identified; 70% of the infections were community acquired. The frequency of each infection during the study period was: bacteremia (N = 12), pneumonia (N = 18), definite urinary tract infection (N = 26) and probable urinary tract infection (N = 17). Initial treatment was appropriate in 49 of 73 (67%) episodes; the organism(s) isolated were resistant to initial therapy in 24 of 85 (33%) episodes. After culture results were available, 34 of 73 (47%) regimens were changed, but only 50% of the changes were considered appropriate. Overall, there was no significant difference in the proportion of all treatment regimens considered appropriate before (67%) and after (56%) culture results were known. We conclude that results of cultures and antibiotic susceptibility data had little influence on appropriateness of antibiotic prescribing in the hospital setting.

Anti-Bacterial Agents↗
PubMed1997

Intraspecific Differentiation of Vibrio vulnificus Biotypes by Amplified Fragment Length Polymorphism and Ribotyping.

The intraspecific genomic relatedness of 80 Vibrio vulnificus isolates, 44 of biotype 1 and 36 of biotype 2, from different geographic origins and sources was evaluated by ribotyping and AFLP (amplified fragment length polymorphism) fingerprinting. Ribopatterns of DNAs digested with KpnI and hybridized with an oligonucleotide complementary to a highly conserved sequence in the 23S rRNA gene revealed up to 19 ribotypes in the species, which were different for the two biotypes. Sixteen different ribotypes were found within biotype 1 strains from clinical and environmental sources, and only three, recovered mainly from diseased eels, were found within biotype 2. Within this biotype, 96% of the strains showed the same ribopattern. The closest similarity was shown by the strains coming from the same eel farm, irrespectively of biotype. AFLP fingerprints obtained by selective PCR amplification of HindIII-TaqI double-restricted DNA fragments exhibited a strain-specific pattern which allowed the finest differentiation of subgroups within the eel-pathogenic isolates sharing the same ribopattern. Both techniques revealed good genetic markers for intraspecific differentiation of V. vulnificus. Ribotyping clearly separated the eel-pathogenic strains from the clinical and environmental isolates, whereas AFLP enabled the monitoring of individual strains and therefore constitutes one of the most discriminative tools for epidemiological and ecological studies.

Journal Article↗
PubMed2000

Distribution and antibiotic resistance of isolates from lower respiratory tract and blood cultures from patients in three Italian intensive care units: a 2-year comparison.

The distribution and antibiotic resistance of major pathogens isolated from patients in ICUs were studied by three Italian microbiological laboratories. Consecutive aerobic strains were collected over two different time periods from protected brushing bronchoscopy, broncho-alveolar lavage and blood cultures. A total of 420 strains were isolated during the first period (47.3% gram-negative and 52.7% gram-positive) and 412 over the second period (50.5% gram-negative and 49.5% gram-positive). Pseudomonas aeruginosa was the most frequently isolated organism from the respiratory tract followed by Staphylococcus aureus. Methicillin resistance was 47.9 and 44.5% in S. aureus and 63.0 and 65.1% in coagulase-negative staphylococci over the two periods. No glycopeptide-resistance was found in gram-positive organisms. Ceftazidime-resistance in Klebsiella pneumoniae was very high.

Anti-Bacterial Agents↗
PubMed2006

Prevalence and antimicrobial resistance of Campylobacter jejuni and Campylobacter coli isolated from raw chicken meat and human stools in Korea.

Prevalence of Campylobacter in raw chicken meat and human stools and subsequent antibiotic resistance profiles of the pathogenic isolates obtained from 2000 through 2002 were investigated. Campylobacter jejuni and Campylobacter coli were isolated from 570 of the 923 raw chicken meat samples collected from traditional markets, large retail stores, or department stores in Korea, resulting in the isolation rate of 61.8%. A total of 579 Campylobacter isolates were obtained from raw chicken (36.3% for C. jejuni and 26.4% for C. coli) with the average population of 335.6 CFU/g. From 513 human stool samples, 15 isolates of Campylobacter were detected. Seasonal variation in the quantification of C. coli was not noticeable throughout the year, while the isolation rate of C. jejuni was the highest in September through October (840 CFU/g) followed by that of July through August and May through June in decreasing order, showing a significant seasonal effect (P < 0.05). Contamination of Campylobacter was more severe in raw chicken meat sold in traditional markets than in those sold in large retail stores and department stores. Prevalence of Campylobacter in raw chicken sold in traditional markets was significantly influenced by seasonal changes (P < 0.05), whereas the samples obtained from other places was less affected by the seasonal changes. Susceptibilities of the 594 chicken isolates to ciprofloxaxin, chloramphenicol, erythromycin, kanamycin, nalidixic acid, and tetracycline were determined by an E-test. Campylobacter isolates were the most resistant to nalidixic acid (91.4%) followed by ciprofloxaxin (87.9%), tetracycline (87.2%), kanamycin (30.6%), erythromycin (19.4%), and chloramphenicol (1.3%). Human isolates showed a similar resistance to the six antibiotics tested. The proportion of Campylobacter isolates with multidrug resistance to four or more antimicrobials obtained from 2000 through 2002 ranged from 28 to 43.5%, indicating that it could be a serious health-threatening factor. This study suggests that it is prudent to establish an effective National Monitoring Program in Korea for the prevention and control of Campylobacter spp.

Animals↗
PubMed1985

A review of the use of cefotaxime in the treatment of skin and skin structure infections, with special reference to gram-positive pathogens.

Data compiled from computer-generated summaries of patient records submitted to Hoechst-Roussel Pharmaceuticals were reviewed regarding the efficacy and toxicity of cefotaxime in the therapy of skin and skin structure infections associated with gram-positive pathogens. In addition, published open and comparative trials employing cefotaxime in gram-positive and gram-negative skin infections were evaluated with respect to the pathogens isolated and the nature, severity and bacteriological and clinical outcome of the treated infections. Within the limitations of the data reviewed, cefotaxime appeared to be a safe and effective therapy in greater than 90% of infections including cellulitis, abscesses and necrotizing ulcers of the skin and subcutaneous tissues when associated with the isolation of susceptible gram-negative bacilli, methicillin-susceptible Staphylococcus aureus, or aerobic or anaerobic gram-positive pathogens susceptible to aqueous penicillin G. The data would indicate that cefotaxime is a suitable therapy for patients with presumed polymicrobial, non-crepitant infections of the skin or skin structures pending microbiological studies. However, cefotaxime cannot be recommended for similar infections due to organisms such as methicillin-resistant S. aureus or Pseudomonas aeruginosa that are commonly resistant to cefotaxime in vitro. Data regarding skin and skin structure infections associated with Clostridium spp. and enterococcal group D streptococci are either lacking or inconclusive with respect to the utility of cefotaxime.

Bacterial Infections↗
PubMed2001

A European perspective on nosocomial urinary tract infections I. Report on the microbiology workload, etiology and antimicrobial susceptibility (ESGNI-003 study). European Study Group on Nosocomial Infections.

OBJECTIVES: To obtain information on the microbiology workload, etiology and antimicrobial susceptibility of urinary tract infection (UTI) pathogens isolated in European hospitals. MATERIALS AND METHODS: We collected data available in the microbiology units of a large sample of European hospitals regarding the laboratory workload, diagnostic criteria, and etiology and antimicrobial resistance of the urinary isolates collected on one day (the study day). RESULTS: Data were received from a total of 228 hospitals from 29 European countries. The average rate of urine samples cultured per 1000 admissions in 1999 was 324. The criteria to consider a positive urine culture as significant were quite variable; > or =10(4) colony-forming units (CFU)/mL for bacteria or > or =10(3) CFU/mL in the case of yeasts were the most used cut-off points. On the study day, a total of 607 micro-organisms from 522 patients with nosocomial UTI were isolated. The six most commonly isolated micro-organisms were, in decreasing order: Escherichia coli (35.6%), Enterococci (15.8%), Candida (9.4%), Klebsiella (8.3%), Proteus (7.9%) and Pseudomonas aeruginosa (6.9%). Pseudomonas was isolated more frequently in non-EU countries. The study data reveal high rates of antimicrobial resistance in UTI pathogens, especially in non-EU countries, where Pseudomonas aeruginosa presented rates of aminoglycoside resistance as high as 72% to gentamicin, 69.2% to tobramycin and 40% to amikacin. CONCLUSIONS: Nosocomial UTI accounts for an important proportion of the workload in microbiology laboratories. A consensus on the practice and interpretation of urine cultures in Europe is needed. The levels and patterns of resistance of UTI pathogens must be a serious cause for concern and a clear reason for stricter guidelines and regulations in antimicrobial policy.

Anti-Bacterial Agents↗
PubMed2004

The maintenance of extreme amino acid diversity at the disease resistance gene, RPP13, in Arabidopsis thaliana.

We have used the naturally occurring plant-parasite system of Arabidopsis thaliana and its common parasite Peronospora parasitica (downy mildew) to study the evolution of resistance specificity in the host population. DNA sequence of the resistance gene, RPP13, from 24 accessions, including 20 from the United Kingdom, revealed amino acid sequence diversity higher than that of any protein coding gene reported so far in A. thaliana. A significant excess of amino acid polymorphism segregating within this species is localized within the leucine-rich repeat (LRR) domain of RPP13. These results indicate that single alleles of the gene have not swept through the population, but instead, a diverse collection of alleles have been maintained. Transgenic complementation experiments demonstrate functional differences among alleles in their resistance to various pathogen isolates, suggesting that the extreme amino acid polymorphism in RPP13 is maintained through continual reciprocal selection between host and pathogen.

Alleles↗
PubMed2001

Protozoan enteric infection in AIDS related diarrhea in Thailand.

The aim of this study was to determine the prevalence of enteric protozoa and other pathogens in AIDS patients with diarrhea in Bangkok, Thailand. Of 288 consecutive patients screened in the 10 month period between November 1999-August 2000 inclusive, 55 (19.2%) had Cryptosporidium spp, 13 (4.5%) had Isospora oocyst, 11 (3.8%) had Giardia lamblia, 3 (0.9%) had Entamoeba histolytica, and 1 (0.3%) had Iodamoeba butschlii infection. The prevalence of microsporidia was 11% in this study. Of 251 patients for whom stool culture for bacteria was performed, enteric bacterial pathogens isolated were Campylobacter spp in 18 (7.1%), Salmonella spp in 11 (4.3%), and Shigella spp in 1 (0.5%). Other pathogens found in these patients were Clostridium difficile in 16/102 (15.6%). Mycobacterium spp in 18/287 (6.2%), and Strongyloides stercoralis in 23/288 (8.0%). Overall, parasitic and bacterial pathogens were identified in 140 (48.6%) patients. These pathogens were identified by the routine simple wet smear technique in 32, formalin-ether concentration method in 46, culture for S. stercoralis in 5, and culture for bacteria in 30. Additional test, using modified Ziehl-Neelsen staining, identified cryptosporidial oocyst, isospora oocyst, and Mycobacterium spp in 72. The microsporidia, initially identified by modified trichrome blue staining, all were then determined to be Enterocytozoon bieneusi by thin sectioning electron microscopy. Protozoan and bacterial pathogens were confirmed to be important etiologic agents in diarrhea in AIDS in Thailand. They were all associated with increased mortality. Routine stool examination by simple wet smear detected only one-fourth of these pathogens. Therefore all diagnostic techniques for these organisms should be made more widely available in Thailand.

AIDS-Related Opportunistic Infections↗
PubMed2006

Enrofloxacin use in a long-distance transport model of equine respiratory disease.

Successful clinical management of bacterial pneumonia in horses depends on the administration of an appropriate antimicrobial agent at an adequate dosage and frequency, given by the correct route of administration for an adequate duration. Empiric antimicrobial therapy should be based on the clinician's experience and current veterinary literature. Based on the frequency of Gram-positive bacterial pathogens isolated from horses with bacterial pneumonia, every effort should be made to provide antimicrobial coverage for this class of pathogens. Gram-negative pathogens may co-exist; therefore, broad spectrum antimicrobial coverage may be necessary. Antimicrobial agents posing potential drug related risks (e.g. nephrotoxicity in dehydrated patients, peracute colitis in racehorses) may not be appropriate for empiric use and enrofloxacin offers an enhanced spectrum of antimicrobial activity with reduced risk of complication. Our findings indicate that in cases of exclusive Gram-positive respiratory disease, solo therapy with enrofloxacin is not indicated.

Animals↗
PubMed1986

Imipenem therapy for perforated and gangrenous appendicitis.

A matched patient control study of imipenem therapy of patients with perforated or gangrenous appendicitis was performed. Thirty-three patients treated with imipenem and cilastatin were compared with 66 control patients treated with clindamycin and gentamicin. Patients were matched for age and surgical pathologic factors. Twenty-five of the 33 imipenem treated patients had perforated (two with abscesses) and nine had gangrenous appendicitis. Anaerobes were recovered from 23 of 32 (72 per cent), anerobes from 31 of 32 (97 per cent) and Pseudomonas from six (26 per cent) of the 23 with perforated appendicitis. Only one isolate, a Fusobacterium species was resistant to imipenem. Enterococci were isolated only from three imipenem treated patients, all were susceptible and were not associated with failures. Frequency of other pathogens isolated was similar for the imipenem and clindamycin and gentamicin patients. One failure occurred in the imipenem treatment group. Failures and adverse reactions were not different for the two groups. The study would have detected as significant (p equals 0.03) a 9 per cent difference in failure rates. Mean days of fever of more than 38 degrees C and days of hospitalization were fewer (p less than 0.05) for imipenem treated patients even when only patients with perforated appendicitis were compared. Days to return of intestinal function were fewer for control patients. Imipenem and cliastatin appeared to be an effective antimicrobial agent used as an adjunct to surgical treatment for peritonitis associated with appendicitis even when caused by Bacteroides fragilis group organisms or Pseudomonas species, or both.

Adult↗
PubMed1986

[Antibiotic sensitivity of the microflora isolated from the uterine cavity of patients with postabortion endometritis].

Examination of the uterus cavity microflora in 50 patients with endometritis post abortum revealed that the etiology of endometritis post abortum was polymicrobial and its development was mainly due to aerobic and anaerobic microbial associations. By the isolation frequency enterococci predominated among the aerobic organisms and bacteriods and fusobacteria predominated among the anaerobic organisms. All the pathogens isolated from the uterus cavity were characterized by polyresistance to antimicrobial drugs. The aerobic bacteria were often resistant to the antibiotics active against the anaerobic organisms which required the use of combined antibacterial therapy in some cases.

Abortion, Spontaneous↗
PubMed1994

Antimicrobial susceptibility of pathogenic Yersinia enterocolitica isolated in Canada from 1972 to 1990.

Yersinia enterocolitica has emerged as an enteropathogen associated with several types of human infections that often require antimicrobial therapy, but little is known about the antimicrobial susceptibilities of pathogenic strains isolated from humans in Canada. To determine the present patterns of antimicrobial susceptibility, to identify changes in these patterns that occurred during the past two decades, and to investigate the relationships between O serotypes and patterns of susceptibility, we tested a total of 1,105 pathogenic Y. enterocolitica strains isolated during 1972 to 1976, 1980, 1985, and 1990 for their susceptibilities to 22 antimicrobial agents. Susceptibility testing was performed by using a single breakpoint concentration in agar procedure. The results showed that all strains were susceptible to ciprofloxacin and piperacillin, and 98% or more of the strains from each period were susceptible to trimethoprim, sulfamethoxazole, cotrimoxazole, tetracycline, chloramphenicol, cefamandole, cefotaxime, aztreonam, and four aminoglycosides. In contrast, all strains were nonsusceptible to erythromycin, furazolidone, and clindamycin and 90% or more of the strains from each period were nonsusceptible to ampicillin, carbenicillin, ticarcillin, and cephalothin. Strains belonging to serotypes O:3, O:5,27, and O:8 had different patterns of susceptibility to ampicillin, carbenicillin, ticarcillin, and amoxicillin-clavulanic acid. No major difference in susceptibility was observed between any of the groups of human or animal strains included in the study, but nonsusceptibility to tetracycline increased from 0.4% in 1985 to 2% in 1990 in human strains isolated in those years. Our results indicate that between 1972 and 1990 there was no marked decrease in susceptibility to agents commonly used for therapy among pathogenic Y. enterocolitica strains isolated in Canada.

Animals↗