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PubMed1995

[Isolation of pathogenic Mycobacterium strains in cattle slaughtered in the abattoir of Bobo-Dioulasso, Burkina Faso].

The major cause of meat rejection at the slaughterhouse of Bobo-Dioulasso is bovine tuberculosis. The objective of this work was to confirm the postmortem diagnosis pronounced at the slaughterhouse using laboratory methods (direct examination following Ziehl-Hielsen staining and isolation of Mycobacterium strains following culture in a Loewenstein-Jensen medium. During the study, 39 pathogenic Mycobacterium strains (38 Mycobacterium bovis and 1 Mycobacterium tuberculosis) out of 100 sampled out suspicious strains, were studied. No Mycobacteria typical of M. farcinogenes was found on direct examination. We were then able to differentiate between bovine tuberculosis and bovine farcy. The results confirm the well-founded decision in the slaughterhouse to discard the meat on the grounds of tuberculosis. The majority of cattle is located in villages around Bobo-Dioulasso and its is therefore highly likely that the disease is enzootic in the area with a fairly high level of infection in animals.

Abattoirs↗
PubMed1981

The isolation of pathogenic fungi and actinomycetes from soil in Egypt.

140 soil samples from the Assiut governorate were examined for pathogenic fungi and actinomycetes. The paraffin-bait technique and a modified sodium citrate-utilizing procedure were used for recovery of Nocardia strains. Five isolations of N. brasiliensis were made by the sodium citrate method while 3 isolates were obtained by the other method. N. gypsoides was isolated for the first time, only the the modified method. It appears that the latter method suppresses to a great extent the growth of saprophytic fungi, hence increasing the possibility of the isolation of Nocardia spp. The effect of keratin enrichment on the isolation of dermatophytes from soil by the hair-bait technique was also investigated. Pretreatment of samples with dog hair or feathers increased the yield of isolates of Microsporum gypseum, Trichophyton terrestre and to a lesser extent, T. mentagrophytes, M. canis was recovered from soil only after its enrichment with dog hair. It is suggested that enrichment with other forms of keratinous material, either separately or in combination, might increase the recovery of keratinophilic fungi from soil.

Egypt↗
PubMed1986

Isolation of Pathogenic Bacillus circulans from Callus Cultures and Healthy Offshoots of Date Palm (Phoenix dactylifera L.).

Pure cultures of a gram-negative, rod-shaped bacterium, which produced endospores after 3 to 5 days on solid medium, were isolated exclusively from tissue cultures of the date palm Phoenix dactylifera L. Electron microscopic examination of thin sections of the bacteria revealed the bilayer membrane typical of gramnegative bacteria and confirmed the nature of the spores as true endospores. Biochemical and physiological tests indicated that the bacteria were Bacillus circulans. B. circulans was consistently isolated from the internal tissues, including the meristem, of apparently healthy offshoots of date palm. When meristem and embryo callus tissue culture samples were injected with B. circulans isolated from similar tissue culture samples and from offshoots, the majority of the isolates produced a rapid, destructive soft rot of the tissues.

Journal Article↗
PubMed1984

Isolation of a DNA plasmid in the fungus Rhizoctonia solani.

A DNA plasmid, designated pRS64, was detected in three isolates of anastomosis group 4 (AG-4) of Rhizoctonia solani Kühn by biophysical methods. The plasmid was a linear double-stranded DNA with a molecular weight of 1.68 +/- 0.06 X 10(6) or 2617 +/- 87 bp. Weakly pathogenic isolates of R. solani, 1668 RI-1, 1271 RI-64 and 1272 RI-1, which showed abnormally slow growth, contained the plasmids, but pathogenic isolates, 1668, 1271 and 1272, showing normal growth, contained no detectable plasmid DNA.

DNA, Fungal↗
PubMed2003

Analysis of sepsis in allogeneic bone marrow transplant recipients: a single-center study.

We reviewed the records of 235 consecutive recipients of allogeneic bone marrow transplantation (allo-BMT) at our center between February 1983 and October 2000. Sepsis occurred in 25 patients (10.6%) at a median of 10 days (range, 1-280 days) after BMT. Five of the 25 patients (20%) died of sepsis. Pathogens isolated from blood culture were gram-positive cocci in 19 patients, gram-negative rods in 7, fungi in 2, and others in 1 patient. Two pathogens were detected concomitantly in 4 patients. Univariate analysis revealed that risk factors for sepsis were selective gut decontamination using lomefloxacin hydrochloride and nystatin, an unrelated donor, HLA mismatched BMT, and stomatitis. Multivariate logistic regression analysis revealed that an unrelated donor was the only significant independent risk factor, with a relative risk of 5.432. In 12 of 25 patients with sepsis, the pathogens of sepsis were sensitive to antibiotics used for gut decontamination. Selective gut decontamination significantly increased the incidence of sepsis, especially that with gram-positive cocci, but not the mortality rate of sepsis, compared with total gut decontamination using vancomycin. We also found a significant relationship between pathogens isolated from blood culture and those isolated from surveillance cultures of stool, urine, and gargled water in the period before sepsis occurred. The present study revealed an independent risk factor for sepsis (unrelated donor), the feasibility of selective gut decontamination, and the importance of surveillance culture.

Adolescent↗
PubMed1993

Neonatal bacterial meningitis in the middle belt of Nigeria.

A three-year prospective study of neonatal meningitis in a tertiary hospital in Nigeria was carried out to determine its clinical spectrum and particular characteristics. The 36 infants studied represented a high incidence of 1.9 per 1000 live births, and the infection was significantly higher among low-birthweight babies. Non-specific signs and symptoms were common, and temperature instability was a constant finding. Specific neurological manifestations were noted that differed from other reports in the literature and contributed significantly to outcome. The most common aetiological pathogen isolated was Gram-positive Staphylococcus aureus and the most common Gram-negative organisms were Klebsiella spp: there was no case of group B streptococci. The pathogens isolated were also at variance with other reports. The mortality rate was 33 per cent and was higher for females. There was no significant difference in outcome between inborn and referred infants, nor between early onset and late onset of the disease. A bulging anterior fontanelle was a significant indicator of poor prognosis. Gentamicin and ceftazidime were the most appropriate antibiotics.

Female↗
PubMed2002

[Bacterial pathogens in sputum and degree of bronchial obstruction in patients with acute exacerbation of chronic obstructive pulmonary disease].

In 114 patients with acute exacerbation of chronic obstructive pulmonary disease (AECB) we performed a microbiological sputum study. In four sub-groups of patients, divided on the basis of the isolated pathogens, we looked for the best forced expiratory volume in one second (FEV1) registered in a previous test (< 12 months), in stable clinical conditions. In 65 samples of sputum (57% of all) the distribution of the isolated pathogens was: H. parainfluenzae 23%, H. influenzae 8%, M. catarrhalis 3%, S. pneumoniae 4%, Enterobacteriaceae (EN) 22%, Pseudomonas and other related germs (BN) 32%, S. aureus 8%. EN and BN showed high sensitivity to various antibiotics. In the patients of the BN sub-group the mean FEV1 showed a significant lower value than in the other sub-groups (from p < 0.01 to p < 0.001). The high percentage of EN and BN seems to be likely explained by the population we studied because there were many subjects with severe clinical and functional conditions, with many comorbidity and frequently treated with oral steroids and antibiotics. The association between the lowest values of FEV1 in stable clinical conditions and the isolation of BN in sputum during AECB could be useful in the choice of the empiric antibiotic therapy during exacerbations.

Acute Disease↗
PubMed1986

Presence of respiratory viruses in middle ear fluids and nasal wash specimens from children with acute otitis media.

During a 28-month period, 84 children with acute otitis media were studied by viral and bacterial cultures of middle ear fluid and viral cultures of nasal lavage fluid. Viruses were isolated from the middle ear fluid of 17 (20%) patients. Evidence of viral infection was demonstrated by positive viral cultures of middle ear fluid and/or nasal lavage fluid in 33 (39%) patients. Rhinovirus in one patient and influenza b virus in another were the only pathogens isolated. Influenza virus, enterovirus, and rhinovirus were the most common viruses found in middle ear fluids. Parainfluenza virus, adenovirus, and respiratory syncytial virus were found less often. In 82% of cases, the virus isolated from middle ear fluid was also isolated from nasal lavage fluid, but only 44% of viruses found in nasal lavage fluid were also found in middle ear fluid. Mixed bacterial and combined viral-bacterial infections were common. Only 15% of patients had no pathogen isolated from middle ear fluids. Using tissue culture techniques, we demonstrated that enterovirus and rhinovirus are also common middle ear pathogens. Our data reemphasize the significance of viruses as etiologic agents of acute otitis media and propose several questions regarding the viral-bacterial interactions and the types of viruses involved in the pathogenesis of the disease.

Acute Disease↗
PubMed2000

Analysis of Leptospira isolates from mainland Portugal and the Azores islands.

From 228 recent Leptospira isolates from mainland Portugal and Azorean wild mammals, 149 were characterized at the serovar level by monoclonal antibodies (MAbs), a quick serological method in epidemiological studies. In order to compare this antigenic information with that from new genetic techniques, a sample of isolates was analyzed through pulsed-field agarose gel electrophoresis (PFGE) (n=71), mapped restriction site polymorphisms (MRSPs) in PCR-amplified rRNA genes (n=45, including 13 saprophytes) and arbitrarily primed polymerase chain reaction (AP-PCR) fingerprinting (n=32). MRSP and AP-PCR lead to species identification of the studied 32 pathogenic isolates: Leptospira interrogans (n=3), Leptospira kirschneri (n=8) and Leptospira borgpetersenii (n=21). MAbs and PFGE characterized pathogenic isolates at the serovar level and resulted mainly in agreement (64%) although many discrepancies (35%) were observed.

Animals↗
PubMed1998

Susceptibility survey of piperacillin/tazobactam and some beta-lactam comparators in Italy.

From September 1994 to March 1995 an Italian multicenter in vitro study to evaluate the susceptibility of piperacillin/tazobactam compared with that of imipenem, ceftazidime, ceftazidime, ceftriaxone, cefotaxime and ampicillin/sulbactam against aerobic bacterial pathogens isolated in 132 different hospitals, was undertaken. In total, 26,732 isolates were collected but only 25,266 aerobic bacteria were able to be evaluated (16,863 Gram-negative and 8,403 Gram-positive). Escherichia coli was the most frequent pathogen isolated (25.9%) followed by Staphylococcus aureus (14.9%), Pseudomonas aeruginosa (13.9%), Enterococcus faecalis (8.2%) and Klebsiella pneumoniae (5.9%). Piperacillin/tazobactam had a general spectrum of activity (84.8% susceptible strains) comparable to imipenem (87.9%), and was distinctly greater than ceftazidime (71.1%).

Anti-Bacterial Agents↗
PubMed1997

Identification of pathogenic strains within serogroups of Yersinia pseudotuberculosis and the presence of non-pathogenic strains isolated from animals and the environment.

The existence of apathogenic strains of Yersinia pseudotuberculosis (Yp) has not so far been reported. Recently, the authors characterized new serogroups and a new subgroup in Yp, that is, O9, O10, O12, O13 and O14 and O1c, and the pathogenicity of these new strains was of interest. A total of 137 strains of serogroups O1c, O6, O7, O9, O10, O11, O12, O13 and O14 of Yp were investigated for their pathogenicity in vivo and in vitro. Although catalase activity and the inv gene were detected in all strains except those of groups O13 and O14, only a few strains, from serogroups O6 and O10 caused severe infection in mice. The remaining strains caused no mortality or severe infection even when they grew in limited tissues of infected mice. All the strains of Yp not possessing the virulence plasmid p YV caused no severe infection in mice. It is evident that less pathogenic Yp exists and that not only pathogenic but also less pathogenic Yp organisms exist in the same serogroup.

Animals↗
PubMed2006

A retrospective study of the aetiology and temporal distribution of bovine clinical mastitis in smallholder dairy herds in the Dar es Salaam region of Tanzania.

A 31-year record-based retrospective study was carried out to determine the aetiology and temporal distribution of bovine clinical mastitis in smallholder dairy herds in the Dar es Salaam region of Tanzania over the period November 1971-December 2002. Laboratory information on 1964 quarter samples from 1365 cows in 281 smallholder dairy herds were retrieved, compiled and studied. Eighty-eight percent of the quarter samples were culture-positive and the predominant mastitis pathogens isolated were Staphylococcus aureus (25.7%), Streptococcus agalactiae (15.4%), Klebsiella pneumoniae (14.3%) and Escherichia coli (14.1%). Other isolates included Pseudomonas aeruginosa (7.5%), Streptococcus dysgalactiae (5.2%) and Streptococcus uberis (4.2%). Contagious mastitis pathogens were isolated from 45.6% of the culture-positive samples, whereas environmental and miscellaneous pathogens were isolated from 48.2% and 5.7%, respectively. Thirty percent of the miscellaneous mastitis pathogens were Candida species. The results demonstrate a steady increase in clinical Candida albicans mastitis. The prevalence of Candida albicans has increased from 1% in 1971 to 17.0% in November 2002. Conversely, despite some fluctuations, the prevalence of Staphylococcus aureus, Streptococcus agalactiae, E. coli and K. pneumoniae remain above 10%. The possible risk factors for these observations are discussed.

Animals↗
PubMed1998

The effect of Pseudomonas aeruginosa infection on clinical parameters in steady-state bronchiectasis.

STUDY OBJECTIVE: To investigate the effect of Pseudomonas aeruginosa infection on clinical parameters in Chinese patients with noncystic fibrosis and steady-state bronchiectasis. DESIGN: Prospective, cross-sectional clinicomicrobiological study with informed consent. SETTING: Consecutive outpatient recruitment from a specialist bronchiectasis respiratory clinic. PATIENTS: Outpatients (n = 100; 62 women; 55.1+/-16.7 years old; FEV1/FVC 1.4+/-0.7/2.1+/-0.9 L), who had stable respiratory symptoms for more than 3 weeks. MEASUREMENTS AND RESULTS: Respiratory pathogens isolated from the sputum were: Pseudomonas aeruginosa (33), Haemophilus influenzae (10), Moraxella catarrhalis (2), other Gram-negative bacilli (5), Streptococcus pneumoniae (6), Staphylococcus aureus (5), mycobacteria (3), and yeast (1). Clinical parameters in patients with positive isolation of P aeruginosa were compared with those without the organism in the sputum culture (non-P aeruginosa). In the P aeruginosa group, the FEV1/FVC ratio and sputum volume were lower (p < 0.005) and higher (p < 0.0001), respectively, than those of the non-P aeruginosa group. The FEV1/FVC ratio (< 60%) and sputum volume (grading > 5) were independently associated with a positive sputum isolation of P aeruginosa with odds ratios of 3.1 (confidence interval [CI] 1.2 to 8.4; p < 0.01) and 4.7 (CI 1.6 to 13.3; p < 0.001), respectively. CONCLUSIONS: P aeruginosa is the predominant respiratory pathogen isolated in the sputum of Chinese patients with steady-state bronchiectasis, and its isolation is associated with high sputum output (> or = 75th quartile) and moderately severe airflow obstruction (FEV1/FVC < 60%).

Adult↗
PubMed2005

Epidemiological and microbiological aspects of acute bacterial diarrhea in children from Salvador, Bahia, Brazil.

In the few cases of acute childhood diarrhea that require antimicrobial therapy, the correct choice of the drug depends on detailed previous knowledge of local strains. In order to establish such parameters in our city, we reviewed the results of all 260 positive stool cultures of children between 0 and 15 years of age during two years at a pediatric tertiary care facility in Salvador, Brazil. Bacterial strains had been presumptively identified by culturing in selective media and by biochemical testing, and their antimicrobial susceptibility patterns were automatically detected by the MicroScan Walkaway System. Data about patients' sex and age, monthly distribution of the cases, pathogens isolated and their antimicrobial resistance patterns were recorded. Males corresponded to 55.4% of our sample, and most of our patients (42.7%) were between one and four years of age. Shigella was the commonest pathogen, being found in 141 (54.3%) cultures, while Salmonella was found in 100 (38.4%) cultures and Enteropathogenic E. coli in 19 (7.3%). Salmonella was the main causal agent of diarrhea in children younger than five years old, whereas Shigella was the most frequent pathogen isolated from the stools of children between five and 15 years old. The peaks of incidence correspond to the periods of school vacations. Shigella specimens presented a very high resistance rate to trimethoprim-sulfamethoxazole (90.1%) and to ampicillin (22.0%), while Salmonella presented very low resistance rates to all drugs tested. These data are useful for practitioners and they reinforce the need for continuous microbiological surveillance.

Acute Disease↗
PubMed1993

A novel superantigen isolated from pathogenic strains of Streptococcus pyogenes with aminoterminal homology to staphylococcal enterotoxins B and C.

Streptococcus pyogenes (group A Streptococcus) has re-emerged in recent years as a cause of severe human disease. Because extracellular products are involved in streptococcal pathogenesis, we explored the possibility that a disease isolate expresses an uncharacterized superantigen. We screened culture supernatants for superantigen activity with a major histocompatibility complex class II-dependent T cell proliferation assay. Initial fractionation with red dye A chromatography indicated production of a class II-dependent T cell mitogen by a toxic shock-like syndrome (TSLS) strain. The amino terminus of the purified streptococcal superantigen was more homologous to the amino termini of staphylococcal enterotoxins B, C1, and C3 (SEB, SEC1, and SEC3), than to those of pyrogenic exotoxins A, B, C or other streptococcal toxins. The molecule, designated SSA, had the same pattern of class II isotype usage as SEB in T cell proliferation assays. However, it differed in its pattern of human T cell activation, as measured by quantitative polymerase chain reaction with V beta-specific primers. SSA activated human T cells that express V beta 1, 3, 15 with a minor increase of V beta 5.2-bearing cells, whereas SEB activated V beta 3, 12, 15, and 17-bearing T cells. Immunoblot analysis of 75 disease isolates from several localities detected SSA production only in group A streptococci, and found that SSA is apparently confined to only three clonal lineages as defined by multilocus enzyme electrophoresis typing. Isolates of one of these lineages, (electrophoretic type 2) are strongly associated with TSLS. The data identify SSA as a novel streptococcal superantigen that appears to be more related structurally to staphylococcal enterotoxins than to streptococcal exotoxins. Because abundant SSA production is apparently confined to only three streptococcal clonal lineages, the data also suggest that the SSA gene has only recently been acquired by S. pyogenes.

Amino Acid Sequence↗
PubMed2006

Antimicrobial prophylaxis to prevent surgical site infections in a rural sub-Saharan hospital.

A prospective cohort study was performed to collect baseline data concerning surgical site infections (SSIs) and antimicrobial prophylaxis (AMP) in a remote sub-Saharan district hospital. The SSI rate of 22% was high. Most (88%) of the patients received prophylaxis after incision, and only 5% within the 30-min period before incision. Of all pathogens isolated from SSIs, 60% were resistant to the agent administered. The antibiotics given most frequently were chloramphenicol (60%), aminopenicillins (23%) and benzylpenicillin (15%). Staphylococcus aureus (36%), Escherichia coli (5%) and enterococci (4%) were the pathogens isolated most commonly from SSIs.

Adolescent↗
PubMed2002

Continuous infusion versus intermittent administration of cefepime in patients with Gram-negative bacilli bacteraemia.

The objective of this study was to compare the pharmacokinetics of cefepime administered by continuous infusion and intermittent injection regimens. A prospective, randomized, cross-over study of ten patients with Gram-negative bacilli bacteraemia was conducted. All patients were randomized to receive cefepime either as a 4-g continuous infusion over 24 h for 48 h or a 2-g bolus administered intermittently intravenously every 12 h for 48 h. After 48 h the patients received the alternative dose regimen. Cefepime pharmacokinetic studies were carried out during hours 36-48 after the start of both regimens. All of the pathogens isolated from the blood in 7 patients had a minimum inhibitory concentration (MIC) < 1 microg mL(-1). In both regimens, the serum cefepime concentrations at all time points were higher than the MIC for the pathogens isolated from this study. For the continuous infusion arm, the highest steady-state concentration was 49.80+/-18.40 microg mL(-1) and the lowest steady-state concentration was 41.42+/-16.48 microg mL(-1). The steady-state concentrations were greater than 4 times the MIC of 8 microg mL(-1). For the intermittent injection regimen, the mean trough concentration was 4.74+/-3.99 microg mL(-1). The mean serum cefepime concentration was above 8 microg mL(-1) for 81.66% of the dosing interval. Therefore, we conclude that either continuous infusion or intermittent injection can be used as an effective mode of cefepime administration to achieve bactericidal activity.

Adult↗
PubMed2002

Determination of antimicrobial activity of Cefaclor on common respiratory tract pathogens in Pakistan.

OBJECTIVE: To determine the antimicrobial activity of Cefaclor against common respiratory tract pathogens isolated from patients in Pakistan. SETTING: Department of Microbiology, Liaquat National Postgraduate Medical Centre, Karachi. METHOD: A laboratory analysis was done on 466 isolates of respiratory tract pathogens collected from 13 laboratories from all over Pakistan. Antibiotic sensitivity test was done by Kirby Bauer disc diffusion method and MIC of Cefaclor was determined by 'E' test. RESULT: Of the 163 Streptococcus pneumoniae, 87 Moraxella catarrhalis and 216 Haemophilus influenzae > 95% isolates were susceptible to Cefaclor. The MIC 90 of all these pathogens were < 2 ug. CONCLUSION: Resistance of respiratory tract pathogens to the 2nd generation Cephalosporin, Cefaclor is very low. MIC 90 of Cefaclor against all three common respiratory tract pathogens is < 2 ug, which indicates that Cefaclor would be effective in more than 90% of cases infected with these bacteria.

Cefaclor↗