Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “pathogen isolation”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 289 records · Page 16Linked to original sources

Antagonistic effects of intestinal Lactobacillus isolates on pathogens of chicken.

Twelve Lactobacillus strains isolated from chicken intestine, which demonstrated a strong and moderate capacity to adhere to the ileal epithelial cells in vitro, were used to investigate their inhibitory ability against five strains of salmonella, i.e. Salmonella enteritidis 935/79, Salm. pullorum, Salm. typhimurium, Salm. blockley and Salm. enteritidis 94/448, and three serotypes of Escherichia coli, viz. E. coli O1:K1, O2:K1 and O78:K80. The results showed that all the 12 Lactobacillus isolates were able to inhibit the growth of the five strains of salmonella, and the three strains of E. coli in varying degrees. Generally, they were more effective in inhibiting the growth of salmonella than E. coli. Inhibition of the pathogenic bacteria was probably due to the production of organic acids by the Lactobacillus isolates.

Animals↗

Increased detection of staphylococcal bacteremia using an anti-microbial removal device.

During the period of August 16, 1981, through December 16, 1982, 15-mL blood culture specimens collected at the Seattle Veterans Administration Medical Center (SVAMC) were divided into two aliquots. The first 10-mL aliquot was inoculated directly into aerobic and anaerobic BACTEC (Johnston Laboratories, Towson, MD) vials (DIR); the remaining 5 mL was processed in an resin-containing Antimicrobial Removal Device (Marion Scientific, Kansas City, MO) before transfer to a second, identical set of aerobic and anaerobic vials (ARD). The final volume of inoculated blood from the ARD specimen was half that of the DIR specimen. Both sets of vials were processed using the BACTEC radiometric detection system. One hundred fifty specimen pairs grew 161 significant pathogens; 43 isolates were recovered only from the ARD sample, 39 only from the DIR samples, and 79 from both. Of the 35 isolates recovered from patients receiving anti-microbial agents active against the isolated pathogens, 21 were recovered only from the ARD specimen and 5 only from the DIR specimen (P less than 0.005). Of the 15 S. aureus strains isolated from patients on therapy, 12 were recovered only from the ARD specimen, 2 only from the DIR sample, and 1 from both samples (P less than 0.01). Ten of the 32 isolates of S. aureus recovered from antibiotic-free patients were found only in the ARD specimen and three only in the DIR specimen (P = 0.05). The ARD specimens recovered significantly more S. aureus from all patients regardless of antibiotic status.

Bacteriological Techniques↗

Potential for local and systemic bacterial infection in some occupational groups in Benin City, Nigeria.

BACKGROUND: Many Third World countries may not have adequate facilities for rapid sensitivity testing of antibiotics as an aid to diagnosis and chemotherapy. It may therefore be valuable to relate bacterial carriage on the skin to type of work a person does. METHODS: Given areas of skin in workers from 10 occupational groups were sampled. The bacteria obtained were analyzed after growth on appropriate media. The sensitivity profiles of potential pathogens isolated from these groups, as well as of those (Staphylococcus aureus only) isolated from patients with certified infections, were carried out and the results were analyzed. RESULTS: Staphylococcus aureus constituted the most widely and frequently isolated potential pathogen. Proteus mirabilis, Escherichia coli, and Klebsiella species were also frequent colonizers of skin. There was a statistical relationship between work type and overall prevalence of bacteria on skin (p less than 0.01). Most isolates of the work groups were highly sensitive to gentamicin and cefuroxine but not to penicillin G, ampicillin, and trimethoprim plus sulfamethoxazole; isolates from infected persons were generally more resistant than were the community-acquired ones. CONCLUSIONS: A relationship may exist between the types of bacteria carried on the skin and the type of work in which a person is engaged.

Bacteria↗

Growth of pathogenic Candida isolates anaerobically and under elevated concentrations of CO2 in air.

Individual isolates of seven potentially pathogenic yeast species in the genus Candida all grew to some extent in Eagle's minimal essential medium including serum under elevated concentrations of CO2 and in anaerobic gas jars. The C. glabrata and C. tropicalis isolates had the highest anaerobic growth rates and yields, the C. guilliermondii and C. parapsilosis isolates had the lowest, and the C. albicans, C. krusei and C. pseudotropicalis isolates gave intermediate growth rates and yields. The same relative abilities to grow anaerobically were seen when the seven isolates were cultured in liquid and on agar formulations of a peptone-glucose broth and two media containing Yeast Nitrogen Base.

Aerobiosis↗

Statistical evaluation of a quality control method for isolation of pathogenic Vibrio species on selected thiosulfate-citrate-bile salts-sucrose agars.

The recovery of Vibrio cholerae, Vibrio fluvialis, Vibrio parahaemolyticus, and Vibrio vulnificus, employing eight strains of each species, was studied by using four brands of thiosulfate-citrate-bile salts-sucrose (TCBS) agar prepared according to manufacturers' instructions and following a standardized procedure. A standardized broth inoculum of each strain was placed on duplicate plates of each brand of TCBS agar and also on tryptic soy agar (Difco Laboratories) containing 1% (wt/vol) NaCl, the latter serving as the control. Plates were inoculated in a sequence designed to compensate for bias associated with multiplication of the bacteria during the inoculation procedure. Colony counts and quality of growth were recorded after incubation for 18 h at 35 degrees C. The comparison procedure was repeated four times at weekly intervals. Data were analyzed by using an analysis of variance model. The recovery and quality of growth of each species varied significantly on the different brands of TCBS agar. Significant variability was also identified for some components of the inoculation procedure. Modifications of the inoculation procedure are suggested to minimize sources of variance. A simplified statistical procedure, based on the t test, is described for media quality control for laboratories routinely isolating pathogenic Vibrio spp.

Bacteriological Techniques↗

Isolation of pathogenic yersiniae from wild animals in Bulgaria.

Pathogenic Yersinia strains were isolated between December 1998 and April 1999 from 37 wild animals: rabbit (Lepus europeus), boar (Sus scrofa scrofa), asiatic jackal (Canis aureus), red fox (Vulpes vulpes), mouflon (Ovis musimon), european river otter (Lutra lutra), beech marten (Martes foina), polecat (Musleta putorius) and wild cat (Felis silvestris). It was established that among the wild animals Y. enterocolitica strains of serotype 0:3 predominated, accompanied by Y. pseudotuberculosis strains of serotype 0:3. In one sample from asiatic jackal and one sample from rabbit, Y. enterocolitica serotype 0:8 was isolated. Yersinia enterocolitica and Y. pseudotuberculosis strains were isolated from tonsils and tongues as well as from the viscera--lung, liver, heart, spleen, kidney and lymph nodes, mainly in young animals (1-2 years of age). The results showed that wild animals are a possible natural reservoir for pathogenic Y. enterocolitica and Y. pseudotuberculosis and are included in the epidemiological chain of yersinioses.

Animals↗

Bacterial etiology of acute otitis media and clinical efficacy of amoxicillin-clavulanate versus azithromycin.

BACKGROUND: Acute otitis media (AOM) is one of the most common acute bacterial infection in childhood and also the most frequent reason for outpatient antibiotic therapy. Little recent information about susceptibility patterns of AOM bacterial pathogens in Turkish children has been reported. OBJECTIVE: To determine the bacterial etiology of acute otitis media in children and to compare the efficiency of 3 days course of azithromycin with a 10 days course of amoxicillin-clavulanate. METHODS: This prospective, single blind, randomised comparative study was carried out in 180 children with AOM. Paracentesis was performed for middle ear fluid culture before the first dose antibiotic therapy. Children with acute otitis media were randomised to receive either low dose amoxicillin-clavulanate (45/6.4 mg/kg/day in two divided doses for 10 days) or low dose azithromycin (10mg/kg/day for 3 days). Clinical response was assessed on days 2-4, 11-13, 26-28. RESULTS: Bacterial pathogens were isolated from 108 (60%) of 180 children. Streptococcus pneumoniae was the most common isolated pathogen (39.7%), followed by Haemophilus influenzae (20.7%), Moraxella catarrhalis (15.5%), Staphylococcus aureus (13.8%), Group A beta-hemolytic streptococcus (5.1%), Escherichia coli (3.4%) and Enterococcus faecalis (1.7%). This study demonstrated low resistance rates compared to studies of different countries. Although clinical response rates were better in patients treated with amoxicillin-clavulanate, this was not statistically significant [86.6% (78 of 90)] versus [95.2% (80 of 84)]. Success rates of amoxicillin-clavulanate were high for both S. pneumoniae and H. influenzae. Difference between success rates was not statistically significant (P=0.144 and 0.352). CONCLUSIONS: Bacteria were isolated in 60% of AOM cases. The clinical efficiency of amoxicillin-clavulanate was found to be equal compared to azithromycin in children with acute otitis media.

Acute Disease↗

Comparative evaluation of orally active antibiotics against community-acquired pathogens: a multi-center study in five Mediterranean countries.

In 5 Mediterranean countries 7902 pathogens, all isolated in 1992 and 1993 from community-acquired infections, were studied for susceptibility to the following orally active antibiotics: penicillin G, ampicillin, ampicillin + sulbactam, amoxycillin + clavulanic acid (both 2:1 ratio), cefalexin, cefaclor, cefuroxime, cefetamet, doxycycline and erythromycin. Ten centers in Italy, 4 centers in Greece, 3 centers in Spain, and 1 center in Lebanon and Saudi Arabia contributed to this study; all centers used performed standardized microtiter panels (Sceptor, BBL, Heidelberg, FRG). The most frequently isolated pathogens were Escherichia coli (n = 1267), Proteus mirabilis (n = 843), Klebsiella pneumoniae (n = 771), enteric Salmonella spp. (n = 629), Enterobacter cloacae (n = 486), Citrobacter freundii (n = 383), Streptococcus agalactiae (n = 346), Haemophilus influenzae (n = 298), Streptococcus pyogenes (n = 294), Streptococcus pneumoniae (n = 246), Klebsiella oxytoca (n = 243), and Shigella spp. (n = 185). Statistical analysis was performed for each of the above countries and for all pooled data available. The penicillin antibiotics were the most active compounds against the gram-positive cocci, exceeding the MIC90 values 2- to 8-fold over all cephalosporins. Regarding the gram-negatives (above all Klebsiella spp.) cefetamet was by far the most active compound (MIC90 = 1 mg/l). Regarding the percentage of resistant isolates, there were no striking discrepancies between the centers and countries involved in this study. There was, however, complete cross-resistance in penicillin-resistant S. pneumoniae isolates (MIC90 = 2 mg/l). By far the majority of the penicillin-resistant pneumococci showed additional resistance to doxycycline and erythromycin.(ABSTRACT TRUNCATED AT 250 WORDS)

Administration, Oral↗

A selective procedure for the field isolation of pathogenic Streptococcus spp. of rainbow trout (Salmo gairdneri).

A procedure established for the selective isolation of the species of Streptococcus responsible for rainbow trout streptococcosis in South Africa, consisted of the inoculation of samples into nutrient broth which had been supplemented with 100 micrograms/ml of nalidixic acid, 160 micrograms/ml of oxolinic acid or 200 micrograms/ml of sodium azide. After incubation, the sample was plated onto tetrazolium agar on which the rainbow trout pathogenic Streptococcus species grew as a red colony. The colonies were isolated from the tetrazolium agar and identified as rainbow trout pathogenic isolates by biochemical and serological tests. In the laboratory the selective procedure is capable of detecting about 2 bacteria per ml. This procedure was used in the field and biochemically identical Streptococcus species were found in the mud and a freshwater crab from the water source of a site with a history of streptococcosis.

Animals↗

Efficacy and safety of higher-dose intravenous ciprofloxacin in severe hospital-acquired infections.

In an open prospective study, 54 patients in an interdisciplinary, operative, anesthesiologic intensive care unit were treated with intravenous ciprofloxacin for life-threatening infections. Secondary nosocomial pneumonias were the predominant infection in most patients. A total of 88 causative pathogens were isolated from 50 patients. The most commonly isolated organism was Pseudomonas aeruginosa; Serratia marcescens, Staphylococcus aureus, and Enterobacter sp. were also isolated. Pathogens could not be detected in four patients (three patients with pneumonia, one patient with urinary tract infection). Ciprofloxacin was administered intravenously, either 400 mg every 12 hours or, after a loading dose of 600 mg every 12 hours on Day 1, 400 mg every 12 hours on successive treatment days. A total of 44 patients were treated parenterally, four orally. An additional six patients received ciprofloxacin in both dosage forms as sequential therapy. Serum ciprofloxacin levels were determined by high-performance liquid chromatography in 17 patients. The serum concentrations and the elimination half-life were in accordance with values already published for parenteral doses of 200 and 500 mg ciprofloxacin. Ciprofloxacin clearance was linear even at the high dose (600 mg every 12 hours loading dose) and no cumulative effect was observed. Clinical outcome was very good. Cure was achieved in 21 patients, and clinical improvement occurred in 23 (favorable clinical response rate, 82 percent). Two patients did not respond to therapy, and eight patients were not evaluable. Adverse effects occurred in 12 patients: transient elevation of liver enzymes (seven patients), temporary increase in serum creatinine levels (two), convulsions (two), and exanthem (one). The treatment of severe infections in intensive care patients with higher doses of parenteral ciprofloxacin appears to be considerably more effective than therapy with the doses of intravenous ciprofloxacin recommended to date. Therefore, these preliminary results are the subject of an ongoing double-blind study.

Bacteria↗

Use of antibiotic-loaded polymethylmethacrylate beads for the treatment of extracavitary prosthetic vascular graft infections.

PURPOSE: This study was conducted to assess the efficacy of antibiotic-loaded polymethylmethacrylate (PMMA) beads in the management of lower extremity extracavitary prosthetic arterial graft infection. METHODS: This was a retrospective review of 34 patients treated for vascular surgical site (VSS) infections involving 36 prosthetic lower extremity arterial bypasses using antibiotic-loaded PMMA beads and culture-specific parenteral antibiotics for 4 to 6 weeks. Sites of graft infection were explored, debrided, and cultured. As determined from the results of Gram's stains of VSS purulence, PMMA powder was polymerized with an antibiotic (vancomycin, daptomycin, or tobramycin/gentamicin, or a combination), molded into a chain of beads, and implanted adjacent to the infected graft after debridement and pulsed-spray antibacterial lavage. All wounds were closed primarily with planned exploration to verify sterilization before a graft preservation or in situ replacement procedure. Treatment outcomes, including wound sterilization, were analyzed based on tissue culture isolates, procedures for persistent infection, and freedom from graft infection. RESULTS: Cultures isolated 42 pathogens, (32 gram-positive, 9 gram-negative, 1 Candida albicans) with methicillin-resistant Staphylococcus aureus (MRSA) cultured from 16 (44%) of 36 surgical site infections. As determined from the initial operative Gram's stain or a prior culture result, vancomycin PMMA beads were implanted in 29 of 36 VSS infections at the first procedure; daptomycin (n = 4) or tobramycin (n = 3) beads were implanted in the rest. Repeat VSS exploration and culture results led to an average of 2.5 antibiotic bead replacements before definitive treatment. A sterile (no growth on tissue culture) VSS was achieved in 87% of cases before a graft preservation (n = 16) or in-situ replacement of an infected graft (n = 20) procedure. No patient deaths occurred. Early and late limb salvage was 100%. Infection recurred in 4 (11%) VSSs during a mean 23-month follow-up period, one within 3 months owing to unrecognized bowel injury associated with in situ replacement of an aortofemoral graft limb. CONCLUSION: Antibiotic-loaded PMMA beads may be a useful adjunct in the contemporary surgical management of VSS infection involving a prosthetic graft. Wound sterilization was achieved in most VSSs before graft preservation or an in-situ replacement procedure, including infections caused by MRSA, a pathogen isolated in half of the extracavitary prosthetic graft infections. This preliminary trial shows the potential benefit of this new technique, but further study is required to prove efficacy.

Aged↗

[Clinical evaluation of lung abscess diagnosed by transtracheal aspiration].

We have diagnosed lung abscess according to findings of infiltration with cavity formation on chest X-ray and/or CT-scan and pathogens isolated from transtracheal aspirates. We evaluated the clinical features of 20 patients with lung abscess (18 males and 2 females, mean age; 54.3 years). Diabetus mellitus and periodontal diseases were prominent underlying diseases in patients with lung abscess. Cough was complained in 13 patients, chest or back pain in 9, purulent sputum in 8 and hemosputum in 5 when the patients admitted to our hospital. A temperature higher than 38 degrees C was present in 12 patients but temperature les than 37 degrees C in 2. Multiple microorganisms were cultured from TTA in 15 patients. A mean of 2.7 bacterial species per patient was isolated, aerobes alone being isolated in 2 patients, anaerobes alone in 3, and mixed aerobic and anaerobic isolates in 10. Seventeen strains of aerobes and 35 of anaerobes were isolated. Major pathogens were Streptococcus pneumoniae, Streptococcus intermedius and other in aerobes, and Peptostreptococcus micros, Fusobacterium necrophorum, Prevotella melaninogenica and others in anaerobes. Abnormality of chest X-ray was located on the right upper lobe in 6 patients, the right lower lobe in 6, the left upper lobe in 6, the left lower lobe in 4 and the right middle lobe in 1. All patients were cured only by treatment of antimicrobial agents, but cavity formation on chest X-ray remained in 4 patients after the treatment.

Adult↗

Frequency of Escherichia coli O157:H7 isolation from stool specimens.

During a 6-month period, 7252 faeces specimens were examined for Escherichia coli serotype O157:H7. Forty-nine specimens (0.7%) from 19 patients yielded this organism. Escherichia coli O157:H7 was the third most frequently isolated bacterial pathogen, following Campylobacter jejuni and (or) Salmonella sp. Although regional variation between laboratories determined whether Campylobacter jejuni or Salmonella was the primary bacterial pathogen isolated, E. coli O157:H7 was consistently isolated more frequently than either Shigella or Yersinia enterocolitica.

Adolescent↗

A multicenter comparative study of cefepime versus broad-spectrum antibacterial therapy in moderate and severe bacterial infections.

The safety and efficacy of cefepime empiric monotherapy compared with standard broad-spectrum combination therapy for hospitalized adult patients with moderate to severe community-acquired bacterial infections were evaluated. In an open-label, multicenter study, 317 patients with an Acute Physiology and Chronic Health Evaluation (APACHE II) score ranging from >5 to =19 were enrolled with documented pneumonia (n=196), urinary tract infection (n=65), intra-abdominal infection (n=38), or sepsis (n=18). Patients were randomly assigned 1:1 to receive cefepime 1 to 2 g IV twice daily or three times a day or IV ampicillin, cephalothin, or ceftriaxone +/-aminoglycoside therapy for 3 to 21 days. For both treatment groups, metronidazole, vancomycin, or macrolide therapy was added as deemed necessary. The primary efficacy variable was clinical response at the end of therapy. Two hundred ninety-six (93%) patients met evaluation criteria and were included in the efficacy analysis. Diagnoses included the following: 180 pneumonias (90 cefepime, 90 comparator), 62 urinary tract infections (29 cefepime, 33 comparator), 37 intra-abdominal infections (19 cefepime, 18 comparator), and 17 sepses (8 cefepime, 9 comparator). At the end of therapy, overall clinical success rates were 131/146 (90%) for patients treated with cefepime vs 125/150 (83%) for those treated with comparator (95% confidence interval [CI]: -2.6% to 16.3%). The clinical success rate for patients with community-acquired pneumonia, the most frequent infection, was 86% for both treatment groups. Among the patients clinically evaluated, 162 pathogens were isolated and identified before therapy. The most commonly isolated pathogens were Escherichia coli (n=49), Streptococcus pneumoniae (n=29), Haemophilus influenzae (n=14), and Staphylococcus aureus (n=11). Bacteriologic eradication/presumed eradication was 97% for cefepime vs 94% for comparator-treated patients. Drug-related adverse events were reported in 16% of cefepime patients and 19% of comparator patients. In conclusion, cefepime had higher cure rates compared with broad-spectrum combination therapy as an initial empiric treatment for hospitalized patients with moderate to severe community-acquired infections, including urinary tract infections, intra-abdominal infections, and sepsis.

Abdominal Abscess↗

Species distribution and antibiotic sensitivity of bacteria isolated pre- and postoperatively from patients undergoing transurethral prostatic resection.

The identity and antibiotic sensitivity of the isolated bacteria from 179 patients undergoing transurethral resection of the prostate were analysed. The patients were randomized into a group receiving a short course of cefotaxime in conjunction with the operation and a control group given no antibiotics. Preoperatively 70 patients had bacteriuria (greater than or equal to 10(7) CFU/l) with a predominance of Gram-negative bacteria (57 isolates, mainly Escherichia coli, Enterobacter, Klebsiella ssp, Proteus ssp), although Gram-positive species (24 isolates, mainly enterococci and Staphylococcus epidermidis) were also frequently encountered. Preoperatively isolated pathogens were evenly distributed in both groups and the sensitivity pattern was comparable. In the cefotaxime group postoperative recurrence of the preoperatively identified bacteria occurred in a lower frequency (11/43) than persistence in the control group (24/38). Only Gram-negative pathogens were isolated from patients with postoperative septicemia and upper urinary tract infections indicating that it is most important to direct prophylaxis against Gram-negative bacteria. A high degree of sensitivity against cefotaxime, gentamicin, trimethoprim, co-trimazine and a combination of ampicillin and mecillinam was recorded among both pre- and postoperatively isolated bacteria.

Adult↗

[Nosocomial infections in vascular surgery: 1-year surveillance].

Among the hospital related complications the nosocomial infections are a major source of problems, especially in the Intensive Care and in the Surgery Units. It has been clearly demonstrated that infection control programs, in Surgery Units, have a large benefit in the reduction of surgical site infections (SSIs) rates. The surveillance method, sponsored by the Centers for Diseases Control of Atlanta, is the most consolidated system and it is active since '70 years. We used this method in the Vascular Surgery Unit of Perugia Hospital. During a 12-month period, 668 consecutive patients were enrolled and followed, after surgery, for 30 days (without implantable devices) or 1 year (with prosthesis). A total of 14 (2.1%) patients had SSIs: 4 superficial, 4 deep, 6 organ-space. We isolated 13 pathogens: 8 gram-positive, 4 gram-negative, and one Candida albicians. The most prevalent pathogen isolated was Staphylococcus aureus methicillin-susceptible. This first positive experience will be used for further more generalized work involving the principal surgical Unit of the Umbria Region.

Adult↗

[Bacterial meningitis in adults: a retrospective multicentric study in Tuscany (Italy)].

The Infectious Diseases Unit of Lucca Hospital conducted a multicentric retrospective study to evaluate the epidemiological and clinical features of adult patients affected by bacterial meningitis attending all the Infectious Diseases Units of Tuscany (Italy) from July 1999 to June 2004. A specific questionnaire was sent to all the units to collect information about each case of bacterial meningitis occurring in patients older than sixteen. Patients with meningitis by Mycobacterium tuberculosis were excluded from the analysis. Nine out of 12 Infectious Diseases Units of Tuscany took part in the study and 197 cases were identified. Most cases of meningitis occurred during 2002 with a slight reduction in cases in subsequent years. Streptococcus pneumoniae and Neisseria meningitidis were the most frequently isolated pathogens with an increase in diagnosis from 1999 to 2004; in 23.8% of patients no pathogens were isolated, with a reduction in meningitis from unknown aetiology from 1999 to 2004. Most patients were treated with a combination of two antibiotics, and corticosteroid drugs were added to the therapy; in the group of patients treated with corticosteroid drugs invalidating complications occurred in 23% of cases and 5% of patients died. In all, 27 out of 197 subjects (13.7%) developed invalidating complications and 20 out of 197 patients (10.2%) died.

Adolescent↗