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PubMedDate not supplied

Prospective randomized comparison of imipenem/cilastatin and cefotaxime for treatment of lung, soft tissue, and renal infections.

Thirty-one moderately or severely ill hospitalized patients with proved (25 patients) or suspected (six) bacterial infections were randomly allocated to receive imipenem/cilastatin (16) or cefotaxime (15). The median age, sex, duration of therapy, underlying disease, and types of infection were similar in both groups. Nineteen patients with pneumonia, eight with soft tissue infection, and four with acute pyelonephritis were included. The pathogens isolated included Escherichia coli (six), Streptococcus pneumoniae (five), Streptococcus pyogenes (five), Haemophilus species (four), Proteus species (three), Staphylococcus aureus (three), and Serratia marcescens (two). In the imipenem/cilastatin group, 13 patients were cured of their infections and three showed improvement. In the cefotaxime group, nine were cured, three showed improvement, and three showed no improvement. Nine patients treated with imipenem/cilastatin developed phlebitis, as compared with eight treated with cefotaxime. One patient treated with cefotaxime developed diarrhea. During therapy, potential pathogens were isolated from four patients in the imipenem/cilastatin group (Candida species [two] and Pseudomonas maltophilia [two]), as compared with eight in the cefotaxime group (enterococci [two], Pseudomonas aeruginosa [two], Candida species [two], Acinetobacter anitratus [one], and Pseudomonas fluorescens [one]). There were no recognized superinfections.

Adult↗
PubMed1999

Secretion of beta-chemokines by bronchoalveolar lavage cells during primary infection of macaques inoculated with attenuated nef-deleted or pathogenic simian immunodeficiency virus strain mac251.

Primary infection of macaques with simian immunodeficiency virus (SIV) as a model of human immunodeficiency virus (HIV) infection represents a unique opportunity to investigate early lentivirus-host interactions. In order to gain insight into immunopathogenic events taking place in the lung during lentiviral infection, we analysed lymphocyte expansion in the lung and chemokine secretion by mononuclear cells obtained by bronchoalveolar lavage (BALMCs) during primary infection by a pathogenic and a non-pathogenic SIV. Two groups of cynomolgus macaques were inoculated intravenously with a fully pathogenic isolate of SIVmac251 or with an attenuated, nef-deleted, molecular clone of SIVmac251. Spontaneous MIP-1alpha, MIP-1beta and RANTES production was assessed by ELISA in supernatants of short-term cultured BALMCs. Kinetics of haematological, virological and immunological parameters were investigated simultaneously. All 11 inoculated animals became infected. Monkeys inoculated with the nef-deleted SIV clone exhibited a significantly reduced plasma virus load and a less pronounced accumulation of lymphocytes in the lung compared to monkeys infected with the pathogenic SIVmac251 isolate. Compared to pre-infection levels, we observed an increase in the levels of RANTES, MIP1-alpha and MIP1-beta production in the two groups of monkeys, by the time of peak viraemia. Strikingly, a greater enhancement of RANTES and MIP-1alpha production was detected in monkeys infected with the attenuated virus. Given the potential influence of beta-chemokines on the immune response and virus replication, such results suggest that RANTES, MIP1-alpha and MIP1-beta could contribute to the singular features of the immune response elicited during infection of macaques with an attenuated SIV.

Animals↗
PubMed1995

Expression of P and type 1 (F1) fimbriae in pathogenic Escherichia coli from poultry.

To investigate the expression of P and type 1 (F1) fimbriae in pathogenic avian Escherichia coli, fourteen pap+/fim+ E. coli isolates pathogenic for poultry were grown on four complex or minimal media, and examined for the presence of mannose resistant (MR) and mannose sensitive (MS) hemagglutination (HA), and for P or for type 1 (F1) fimbriae using immunofluorescence, immunodot, and immunoblot. In addition, isolates grown under different culture conditions were examined for adherence to frozen sections of chicken trachea. Twelve of the 14 isolates were divided into three groups based on adhesin expression in the different media. Isolates of all three groups exhibited strong MSHA reactions when cultures were grown serially in static broth, and expressed a subunit protein with an apparent molecular mass of 17 to 18.5 kDa, serologically related to the FIA major fimbrial subunit. There was a good correlation between MSHA and adherence to chicken tracheal sections. Isolates of group I only demonstrated MSHA and expression of F1A fimbriae after growth in static broth. Isolates of group II demonstrated MSHA and expression of F1A fimbriae after growth in all tested media whereas isolates of group III demonstrated expression of F1A fimbriae only after growth in static broth and minimal agar. Only the five group I isolates expressed MRHA associated with P fimbrial adhesins and expressed fimbriae with a major subunit protein of 18 kDa serologically related to the F11 major fimbrial subunit. None of these five isolates grown on complex solid media, where P but not type 1 fimbriae were expressed, adhered to tracheal sections. Results suggest that i) P fimbriae are not readily expressed in vitro by most pap+/fim+ avian E. coli isolates; ii) environmental control of phase variation of type 1 fimbriae differs among pathogenic avian E. coli; and iii) receptors for type 1, but not for P fimbriae, are present in chicken tracheal mucosa.

Animals↗
PubMed1999

Antimicrobial activity of gatifloxacin compared to seven other compounds tested against gram-positive organisms isolated at 10 cancer-treatment centers.

Gram-positive bacterial pathogens are important causes of disease in cancer patients and are becoming increasingly resistant to available antimicrobial agents. We examined the in vitro activity of gatifloxacin, a new fluoroquinolone, compared with other quinolones, ceftazidime, and traditional Gram-positive-active agents tested against pathogens isolated from patients at 10 cancer treatment hospitals in the United States. A total of 1,128 Gram-positive isolates were tested by the E-test method (AB BIODISK, Solna, Sweden) with results validated by concurrent quality control strain analysis. Gatifloxacin was more potent than either ciprofloxacin or levofloxacin against all Gram-positive species. Vancomycin was the most active agent tested against all species except Bacillus spp., which were more susceptible to the fluoroquinolones. When tested against these Gram-positive pathogens from patients with cancer, the spectrum of gatifloxacin was also greater than that of levofloxacin and ciprofloxacin. Gatifloxacin may have a role as part of prophylactic or therapeutic antimicrobial regimens for selected cancer patients with Gram-positive infections.

Anti-Bacterial Agents↗
PubMed2000

In vitro assessment of Metarhizium anisopliae isolates to control the cattle tick Boophilus microplus.

Metarhizium anisopliae is a filamentous fungus used for tick control. The in vitro effects of 12 M. anisopliae isolates on engorged Boophilus microplus females were analysed. The most pathogenic isolate (E6S1) caused a 100% death rate when 10(7) spores/ml were used to infect ticks. Isolates of M. anisopliae taken from experimentally infected ticks proved to be more pathogenic than fungus maintained on culture media. A comparison between dsRNA mycovirus-free and infected M. anisopliae isolates suggested that, in general, virus free isolates were more infective. The results showed that the biological control of B. microplus by M. anisopliae infection might constitute an additional method to integrated tick control management.

Animals↗
PubMed2003

In vitro susceptibility of Streptococcus pneumoniae, Haemophilus influenzae and Moraxella catarrhalis: a European multicenter study during 2000-2001.

OBJECTIVE: To assess the current (2001) activity of respiratory fluoroquinolones and comparator agents against respiratory pathogens isolated in European countries. METHODS: During 2000-2001, we prospectively collected 1995 isolates of Haemophilus influenzae, 1870 isolates of Streptococcus pneumoniae and 649 isolates of Moraxella catarrhalis from hospital laboratories in France, Germany, Greece, Italy, Spain and the UK. National Committee for Clinical Laboratory Standards (NCCLS)-approved broth microdilution antimicrobial susceptibility testing methods and interpretive criteria were used throughout. RESULTS: Of the S. pneumoniae isolates, 99.6% were susceptible to moxifloxacin, gatifloxacin and levofloxacin; the corresponding figure for H. influenzae was 100%. All M. catarrhalis isolates had moxifloxacin MICs </= 0.12 mg/L. For all three pathogens, fluoroquinolone susceptibility remained unchanged from the previous 1997-98 study. The incidence of penicillin non-susceptibility in the S. pneumoniae isolates tested remained similar to or higher than that recorded in previous studies: France, 165/291 (56.7%); Germany, 46/506 (9.1%); Greece, 20/55 (36.4%); Italy, 45/364 (12.4%); Spain, 146/268 (54.5%); and the UK, 26/386 (6.7%). Significant levels of resistance to oral compounds (cefuroxime, cefaclor, cefdinir, clarithromycin, azithromycin, tetracycline, and trimethoprim-sulfamethoxazole) were detected among S. pneumoniae isolates. beta-Lactamase production among H. influenzae isolates ranged from 6.2% to 33.1% per country, and ampicillin, clarithromycin or trimethoprim-sulfamethoxazole resistance were the most common phenotypes detected. beta-Lactamase production among M. catarrhalis isolates ranged from 94.1% to 100% per country. CONCLUSIONS: With the exception of a few localized reports, resistance to moxifloxacin and other new fluoroquinolones in common respiratory pathogens is a rare occurrence, despite significant resistance to other compound classes. Surveillance will play a key role in tracking changes in fluoroquinolone susceptibility in European countries.

Anti-Infective Agents↗
PubMedDate not supplied

[Mark's disease: V. Experimental behavior of 3 isolates taken place in the country].

Three experiments were designed to determine the parameters of virus infection, antibodies and mortality with three different MD isolates inoculated in one day old birds from commercial origin. The animals were divided in three inoculated lots (1-2-3) and three control groups (4-1, 4-2, 4-3) and were followed weekly from hatching through 17 weeks. The former were inoculated respectivelly with FOV-6, FCV-8 and FCV-9. Each day old bird received between 50-75 FPU/bird by I.P. route. Samples were taken from circulating blood of five birds by cardiac puncture with an heparinized syringe (20 U/ml), were centrifuged and the white cells inoculated to 5-15 four day old embryos by yolk salk route for virus detection; plasma was assayed by immunodiffusion against MD antigen in order to detect precipitating antibodies, and mortality was recorded after microscopical examination. Infection appeared to persist indefinitelly in the host chicken flock and coexist with (100%) precipiting antibodies, (Fig. 1-2-3). First virus isolation was accomplished after 4 weeks post-inoculation and the 100% porcentage of antibodies, was found only 1-3 weeks after the first peak of viraemia. With the most pathogenic isolate FCV-6 (ig. 1) the antibody response was significantly delayed. Maternal antibodies decreased more rapidly in inoculated than in control birds. Accumulative mortality showed isolate FCV-6 and FCV-8 as pathogenic strains and FCV-9 strain as less pathogenic. Mortality begun 1-3 weeks after the first peak of virus detection in the flock, independently of the pathogenic pattern of the isolate, but frecuencies of death were markedly different.

Animals↗
PubMed2004

Etiology and susceptibility of urinary tract isolates in Kosova.

Urinary tract infections are amongst the most common pathogenic infections with an increasing resistance to antimicrobials. The objective of this study was to determine the etiology and antimicrobial susceptibility patterns of urinary tract infection pathogens isolated in Kosovo. A retrospective study was carried from urine samples of both inpatients and outpatients that were received in our laboratory throughout 2001. During the study period, 16500 urine samples were analysed, of which 4260 (25.8%) had significant bacteriuria obtained from 1420 patients. Of this, 1059 (74.6%) were collected from females and 361 (25.4%) from males. Urine samples processed from outpatients were 72.5% (1029), whereas 27.5% (391) were from hospitalised patients. Escherichia coli was the most common aetiologic agent isolated (80.5%), followed by Proteus spp. (6.1%), Klebsiella spp. (5.9%), Citrobacter (5.1%) and Mycobacterium tuberculosis (0.8%). Gram-positive bacteria accounted for only 0.3%. Pseudomonas aeruginosa was only isolated from inpatients and was responsible for 0.6% of infections. Amoxicillin, ampicillin and trimethoprim-sulphamethoxazole resistance rates were 48.7, 46.5 and 32.1%, respectively. Nitrofurantoin, cefalexin and ciprofloxacin expressed the highest susceptibility among these isolates. E. coli isolates from inpatients and outpatients showed more than 25% resistance to trimethoprim-sulphamethoxazole. Of all isolates, 16% (225) were resistant to three or more agents and considered multi-drug resistant. Current data on the prevalence of multidrug resistance among urinary tract isolates should be a consideration to change the current empiric treatment of urinary tract infections.

Bacteria↗
PubMed1983

Susceptibility of blood isolates to various antibiotics, in particular to cephalosporins.

Of 760 bacterial pathogens isolated from blood cultures of acutely ill patients in a general hospital in Hong Kong for 1 year, 69.9% of the isolates were Gram-negative aerobes mainly Escherichia coli and Klebsiella pneumoniae, 22.0% were Gram-positive aerobes mainly Staphylococcus aureus and enterococci and 8.1% were anaerobes mainly Bacteroides spp. The susceptibility of the aerobic isolates to various antibiotics was tested. Ampicillin was found to be active mainly against the enterococci and some other Gram-positive organisms while most isolates of Staph. aureus and the Gram-negative bacteria were resistant. In contrast, cephalothin was found only slightly less active than the second generation cephalosporins against Gram-negative blood isolates but considerably more active against Staph. aureus and other Gram-positive isolates. The three aminoglycosides tested, i.e., gentamicin, tobramycin and amikacin, showed similar good activity against E. coli, K. pneumoniae and Proteus mirabilis, but amikacin had the broadest spectrum of activity in inhibiting most of the other Gram-negative isolates as well as isolates of Staph. aureus. The third generation cephalosporins, cefotaxime, cefoperazone, latamoxef (moxalactam), ceftriaxone and ceftazidime, all had a high activity against the Gram-negative but a reduced activity against the Gram-positive bacteria. Ceftazidime had the broadest spectrum of activity in inhibiting all the Gram-negative isolates including Pseudomonas aeruginosa, while cefotaxime showed the best overall activity against both Gram-positive and Gram-negative blood isolates.

Anti-Bacterial Agents↗
PubMed2002

In vitro activity of moxifloxacin against bacteria isolated from odontogenic abscesses.

We evaluated the antimicrobial susceptibility of 87 pathogens isolated from 37 patients with odontogenic abscesses. The most prevalent bacteria were viridans group streptococci and Prevotella species. Considering all bacterial isolates, 100% were susceptible to amoxicillin-clavulanic acid, 98% were susceptible to moxifloxacin and to levofloxacin, 76% were susceptible to doxycycline, 75% were susceptible to clindamycin, and 69% were susceptible to penicillin.

Adolescent↗
PubMed1991

Acid and alkali as aids in differentiation of pathogenic Nocardia and for their isolation from clinical specimens.

The tolerance of Nocardia brasiliensis, Nocardia asteroides and Nocardia caviae to different concentrations of acids and alkalis was studied in this work. The purpose was to determine their use: (a) in the differentiation of species; (b) for decontamination of clinical materials during the isolation of pathogenic Nocardia. The results showed (1) that both 2 M NH3 and 0.05 M H2SO4 solutions are useful for differentiating species. They can also be used as a complementary method for identification. (2) That both 1 M NH3 and 0.05 M H2SO4 solutions were useful for decontamination of clinical materials during the isolation of pathogenic Nocardia.

Acetates↗
PubMed1992

Pathogens in dog bite wounds in dogs in Harare, Zimbabwe.

Over a year swabs were taken from 87 untreated bite wounds in dogs seen by veterinary practitioners in Harare, Zimbabwe. Swabs were also taken from normal skin adjacent to the wound site, and gingival swabs were collected from normal dogs coming to the same clinics. The swabs were cultured aerobically for pathogens, particularly Staphylococcus intermedius, and the antibiotic sensitivities of the pathogens were determined by disc diffusion assay. The most common pathogens isolated from the wounds were S intermedius (23 per cent), Escherichia coli (18 per cent) and non-lactose-fermenting coliforms (14 per cent). S intermedius was common on the normal skin of the dogs with infected wounds, and was associated with wounds on the abdomen, hindlimbs and tail and wounds that were more than three days old. This organism was, however, isolated only infrequently from the gums and there was little correlation in general between the prevalence of pathogens in the mouth and their prevalence in wounds. Of the S intermedius isolates from wounds, 30 per cent were resistant to penicillin and multiple antibiotic resistance was common among the enterobacterial isolates. The majority of the pathogens were sensitive to cotrimoxazole.

Animals↗
PubMed1994

[Herpes simplex digitalis--an important differential diagnosis of paronychia].

Herpes simplex infection of the hand is often falsely diagnosed as a pyogenic paronychia or felon and treated as such, because the clinical picture is not known and pathogen isolation is difficult. However, the surgical treatment of herpes digitalis is contraindicated, since it promotes the development of superinfections and triggers recurrence. The pathogen can be isolated in cell cultures prepared from the vesicle contents or a smear from the vesicle base. Serological antibody testing is unreliable. Topical application of Acyclovir cream (Zovirax) is the treatment of choice.

Acyclovir↗
PubMed1994

Retention of B. burgdorferi pathogenicity and infectivity after multiple passages in a co-culture system.

In vitro cultivation of B. burgdorferi in BSK medium results in the loss of infectivity and pathogenicity after repeated passages. To prevent this loss, a feeder layer of tibio-tarsal joint tissue derived from newborn LEW/N rats was grown on Cytodex 3 microcarriers in ESG (formerly BSKE), a novel medium developed to support the growth of both the feeder layer and B. burgdorferi. A new pathogenic isolate (FNJ) and a high passage, non-pathogenic strain (TNJ) grew well in this co-culture system with high yields of viable organism. FNJ caused no growth inhibition or visible damage to the cells in the feeder layer. FNJ remained arthritogenic for newborn LEW/N rats after 22 passages in the co-culture system, but lost its arthritogenicity after 7 passages when cultured in BSK medium. This borrelia-mammalian tissue co-culture technique presents an experimental system to study the long term interactions of B. burgdorferi with the infected host tissues in vitro, as well as facilitate diagnostic tests and vaccine development.

Animals↗
PubMed1987

Efficacy of trimethoprim-sulfamethoxazole in treatment of acute diarrhea in a Mexican pediatric population.

The efficacy of trimethoprim-sulfamethoxazole (TMP-SMX) and placebo were compared in a randomized double-blind study of 141 Mexican children with acute diarrhea. Patients who met specific entry criteria received TMP-SMX or an identical appearing placebo for 5 days. Stools were examined for bacterial, viral, and parasitic pathogens. Enterotoxigenic Escherichia coli were the most commonly isolated pathogens (22% of total). Patients given TMP-SMX had a significantly shorter time to "last illness stool" than did those given placebo, but no difference in number of unformed stools in 5 days was found between treatment groups. However, TMP-SMX significantly shortened the illness in patients with fever or many fecal leukocytes. When stool cultures positive for any bacterial pathogen or for enterotoxigenic E. coli were analyzed as separate groups, a significantly faster recovery was observed in patients given TMP-SMX. TMP-SMX is efficacious in the treatment of Mexican children with diarrhea and culture-proved bacterial infection or when the clinical signs and symptoms suggest bacterial enteritis.

Acute Disease↗
PubMed1997

Eight-year surveillance of non-albicans Candida spp. in an oncology department prior to and after fluconazole had been introduced into antifungal prophylaxis.

From 1989 until 1996, during the last 8 years, the proportion of Candida (C.) krusei, and other non-albicans Candida spp. isolated from surveillance cultures and from sterile body sites, was analyzed among 13,758 admissions in a National Cancer Institute. During these admissions a total of 9,042 isolates were prospectively collected from surveillance cultures, and 126 from blood cultures. The proportion of C. krusei among all organisms was 12.7% to 16.5% in 1989 through 1991, i.e., before fluconazole was introduced into prophylactic protocols. After the introduction of fluconazole into prophylaxis in acute leukemia in 1992 the incidence of C. krusei was 7.9% to 8.6% during 1994 to 1996. After 5 years of using this drug for prophylaxis, the incidence of C. krusei was lower than before this drug was introduced in our institute. Among yeasts, the most frequently isolated pathogen was still Candida albicans (72.2% of all isolated fungal organisms). Among molds, Aspergillus spp. was the most frequently isolated agent. Analyzing the etiology of proven fungal infections (fungemias) confirmed by positive blood cultures, C. albicans was the most common causative organism in 53.8% of cases. The incidence of fungemia due to Torulopsis (C.) glabrata and C. krusei before and after fluconazole introduction did not change. Of 126 organisms isolated from blood cultures, there was no increase in T. (C.) glabrata or C. krusei after introduction of fluconazole for prophylaxis and therapy, and the quoted 6.4% of fungemic episodes remained stable with an incidence of 1 fungemia/year since 1991. The proportion of C. krusei and C. glabrata among Candida spp. was decreasing in our center between 1989 and 1996. Also, the proportion of non-albicans Candida spp. among isolates decreased from 25.7% in 1990 to 11.9% in 1996.

Anti-Infective Agents↗
PubMed1985

Isolation medium for the recovery of Pseudomonas cepacia from respiratory secretions of patients with cystic fibrosis.

A new medium for the isolation of Pseudomonas cepacia from respiratory tract secretions of patients with cystic fibrosis (CF) is described. This medium consists of inorganic salts, 0.5% pyruvate, and 0.1% proteose peptone as nutritive components and 0.0001% crystal violet, 0.15% bile salts, 100 micrograms of ticarcillin per ml, and 300 U of polymyxin B per ml as selective agents. The medium, designated PC medium, supported superior growth of 38 of 50 stock isolates of P. cepacia after 48 h of incubation when compared with MacConkey agar (0 of 50). The medium completely inhibited the growth of 112 of 124 stock isolates of organisms commonly found in respiratory secretions of CF patients. Cultures were made on PC medium with respiratory secretions of 169 CF patients. P. cepacia was recovered from 35 patients with isolates on PC medium but from only 21 patients with isolates on MacConkey agar. Of 221 other potentially pathogenic isolates found in these specimens, only six (two Pseudomonas aeruginosa isolates, two molds, one yeast, and one Serratia marcescens isolate) grew on PC medium. PC medium should facilitate the recovery of P. cepacia from CF patients.

Child↗
PubMed2003

Hospital-acquired pneumonia: coverage and treatment adequacy of current guidelines.

The American Thoracic Society (ATS) guideline for hospital-acquired pneumonia (HAP) released in 1996 and the Trouillet classification published in 1998 supply different rational foundations for the classification of patients with HAP and for the selection of initial antibiotic therapy. The aims of this study were to assess the level of bacterial coverage and to assess and validate the adequacy of antibiotic strategy of each of these classifications. Intensive care unit-admitted patients (n=71) with suspicion of HAP were evaluated. The ATS and Trouillet classifications demonstrated an accuracy to predict the causative microorganism of 91% and 83% respectively. The ATS and Trouillet antibiotic treatment recommendations were adequate in 79% and 80% of the patients, respectively. The microorganisms implicated in the treatment inadequacy of the ATS guideline were Pseudomonas aeruginosa (n=3), Acinetobacter baumanii (n=1), Stenotrophomonas maltophilia (n=1) and methicillin-resistant Staphylococcus aureus (n=1). P. aeruginosa was implicated with Trouillet treatment inadequacy. The current recommendations for empirical antibiotic treatment of hospital-acquired pneumonia (American Thoracic Society and Trouillet) showed a good ability to predict the involved pathogen. However, considering the resistance pattern of the isolated pathogens, both classifications demonstrated a rather lower treatment adequacy; the main reason was the failure to treat highly resistant strains.

Aged↗