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P Coll

Publications and source records attributed to P Coll.

At least 55 records · Page 3Linked to original sources
PubMed1997

Early microbiologic diagnosis of spontaneous bacterial peritonitis with BacT/ALERT.

BACKGROUND/AIMS: Inoculation of ascitic fluid into conventional blood culture bottles is more sensitive than conventional culture in the diagnosis of spontaneous bacterial peritonitis. BacT/ALERT is an automated colorimetric microbial detection system that has been shown to be faster than conventional blood culture bottles in the diagnosis of bacteremia. The aim of the study was to compare the BacT/ALERT system with the conventional culture and the conventional blood culture bottles method in the diagnosis of spontaneous bacterial peritonitis. METHODS: All the ascitic fluid samples from patients with cirrhosis hospitalized in our Department between September 1992 and May 1994 (n=1032) were prospectively evaluated. In all cases, an aliquot of ascitic fluid was sent for Gram's stain and conventional culture, and 20 ml were inoculated at the bedside into blood culture bottles: 10 ml into conventional blood culture bottles and 10 ml into BacT/ALERT. RESULTS: Thirty ascitic fluid infections (23 spontaneous bacterial peritonitis and 7 neutrocytic ascites) and 20 bacterascites were diagnosed. Conventional culture was positive in 10/30 ascitic fluid infections (33.3%), conventional blood culture bottles in 22/30 (73.3%) (p<0.01 compared to conventional culture) and BacT/ALERT in 20/30 (66.6%) (p<0.05 compared to conventional culture, pNS compared to conventional blood culture bottles). The time elapsed for culture positivity was 43.4+/-34.2 h for conventional blood culture bottles and 13.3+/-9.2 h for BacT/ALERT (p<0.001). Thirteen of the 23 cases of spontaneous bacterial peritonitis (56.5%) were detected within the first 12 h with BacT/ALERT, as compared to only three (13%) with conventional blood culture bottles (p<0.03). CONCLUSION: The automated system BacT/ALERT provides an earlier microbiologic diagnosis of spontaneous bacterial peritonitis than conventional blood culture bottles with similar sensitivity.

Anti-Bacterial Agents↗
PubMed1997

New planetary atmosphere simulations: application to the organic aerosols of Titan.

The atmosphere of Titan partly consists of hazes and aerosol particles. Experimental simulation is one of the powerful approaches to study the processes which yield these particles, and their chemical composition. It provides laboratory analogues, sometimes called tholins. Development and optimization of experimental tools were undertaken in order to perform chemical and physical analyses of analogues under conditions free from contamination. A "Titan aerosol generator" was developed in the frame of the Cassini-Huygens mission, in order to produce Titan's aerosol analogues within conditions closer to those of the titanian atmosphere: cold plasma simulation system, low pressure and low temperature. The direct current (DC) glow discharge is produced by applying a DC voltage between two conductive electrodes inserted into the gas mixture-model of the studied atmosphere- at low pressure. A high-impedance power supply is used to provide the electrical field. All the system is installed in a glove box, which protect samples from any contamination. Finally the research program expected with this new material is presented.

Aerosols↗
PubMed1997

Acquired drug resistance in Mycobacterium tuberculosis isolates recovered from compliant patients with human immunodeficiency virus-associated tuberculosis.

We describe five compliant patients with human immunodeficiency virus (HIV)-associated tuberculosis (TB) that relapsed, with acquisition of resistance by the original Mycobacterium tuberculosis strains. Both the first and second isolates from each patient had the same IS (insertion sequence) 6110-based DNA fingerprint patterns. Three of the five patients developed TB that was resistant to rifampin alone; no mutation in the region of the rpoB gene was detected by a line probe assay in two of the isolates from these patients. We discuss several factors presumably associated with acquired drug resistance in HIV-infected patients, including exogenous reinfection, drug interactions, malabsorption of drugs, and the presence of a large organism burden.

AIDS-Related Opportunistic Infections↗
PubMed1997

Group B streptococcal meningitis in adults: report of twelve cases and review.

Group B streptococcus (GBS) is the leading etiologic agent of bacterial meningitis and sepsis during the neonatal period, but it is an infrequent cause of meningitis in adults. We report 12 episodes of group B streptococcal meningitis in adults and review 52 cases reported in the literature. A total of 24 men and 40 women were included in the study; the mean age (+/- SD) was 49.2 +/- 20.5 years (range, 17-89 years). All the patients had cerebrospinal fluid cultures positive for GBS. Eighty-six percent of the patients had comorbid conditions, 50% had a distant focus of infection, and blood cultures yielded GBS for 78.7%. The overall case-fatality rate was 34.4% (22 patients). Factors associated with a poor outcome were advanced mean age (+/- SD) (61.5 +/- 17.4 years vs. 42.8 +/- 19.2 years; P = .0003) and the presence of complications on admission (P = .0001). Seven percent of survivors had neurological sequelae. Group B streptococcal meningitis in adults has become increasingly frequent in recent years; it tends to occur in patients with severe underlying conditions and is associated with a high case-fatality rate. Factors associated with a poor prognosis are advanced age and the occurrence of neurological and extraneurological complications.

Adult↗
PubMed1997

Epidemiology of an unusually prolonged outbreak of typhoid fever in Terrassa, Spain.

An unusually prolonged outbreak of typhoid fever, from 1988 to 1994, in Terrassa (Barcelona, Spain), was caused by a casual food handler who was a carrier. The pattern of this outbreak suggested intermittent low-level exposure to Salmonella typhi. We found 70 patients with S. typhi infections, 52 of whom were available for study. Medical records were reviewed and patients were interviewed with use of a standard questionnaire. Phage typing and pulsed-field gel electrophoresis (PFGE) for strain subtyping were used to confirm the epidemiological data. The 27 outbreak strains shared the same phage type and the same PFGE pattern. Four sporadic strains shared the same phage type as the outbreak strain. PFGE was found to be useful for differentiating strains for epidemiological purposes.

Adult↗
PubMed1997

Serial surveillance cultures of skin and catheter hub specimens from critically ill patients with central venous catheters: molecular epidemiology of infection and implications for clinical management and research.

A prospective study of 45 central venous catheters was conducted to assess, by strain delineation, the turnover of skin and catheter hub (superficial) colonization and the relative contributions of catheter hub and skin colonization to catheter tip colonization. Serial quantitative cultures of skin and catheter hub were performed. Catheter tip, blood, and specimens for culture from targeted superficial sites (TSSs) were also collected at the time of catheter removal. Strains from 17 tip-positive catheters were delineated by pulsed-field gel electrophoresis. Only 12 (28.6%) of 42 skin strains and 14 (31.1%) of 45 catheter hub strains were found to be present at the time of catheter removal. In addition, only 9 (29.0%) of the 31 tip-colonizing strains were present on TSSs. Moreover, 15 (48.4%) of the 31 tip-colonizing strains had a superficial origin, and the other 16 (51.6%) were of unknown origin. In catheters suspected of infection, cultures of TSSs had a negative predictive value for catheter-related bacteremia of 94.4% but a positive predictive value of 44.4%. When the causative agent was identified (to the strain level) these values dropped to 80.9 and 18.7%, respectively. The study shows that skin and catheter hub colonization is a common, dynamic phenomenon. Strains recovered from TSSs showed a low level of correlation with strains from previous cultures of specimens from superficial sites and catheter tip isolates. Consequently, TSSs cannot be recommended for use in determining the therapy. However, catheter-related bacteremia is uncommon when cultures of TSSs are negative.

Bacteria↗
PubMed1997

Detection of Mycobacterium tuberculosis DNA in lobular granulomatous panniculitis (erythema induratum-nodular vasculitis).

OBJECTIVE: To determine, using polymerase chain reaction (PCR) amplification, if Mycobacterium tuberculosis complex DNA is present in the skin biopsy specimens of lobular granulomatous panniculitis. DESIGN: A retrospective descriptive study. SETTING: A university-based hospital. PATIENTS: From the 65 patients included in the study, we examined 72 paraffin-embedded skin biopsy specimens with a histologic diagnosis of erythema induratum or nodular vasculitis. The biopsy specimens were from the histopathological archives of the Departments of Dermatology and Pathology of the Hospital de la Santa Creu i Sant Pau, Barcelona, Spain, from 1976 to 1994. Twenty-two biopsy specimens were excluded from the final analysis because we could not amplify the internal control. MAIN OUTCOME MEASURES: Detection of a 123-base pair fragment of the IS6110 insertion sequence specific for M tuberculosis complex. RESULTS: The results of PCR amplification were positive for M tuberculosis complex DNA in 77% of the skin biopsy specimens. No significant difference could be detected with respect to the age of the patients, ulceration of the nodules, reactivity to purified protein derivative, abnormal results of a chest x-ray examination, personal and family history of tuberculosis, and PCR results. The presence and degree of necrosis on histologic examination were significantly higher in the PCR-positive group (P = .04). None of the following variables were associated with PCR results: presence of vasculitis, degree of granulomatous infiltrates, number of giant cells, and presence of well-organized granulomas. CONCLUSIONS: The DNA of M tuberculosis can be detected in a considerable number of skin biopsy specimens of lobular granulomatous panniculitis. None of the clinical and histologic variables evaluated could accurately predict the results of PCR amplification.

Adult↗
PubMed1997

Epidemiologic evidence of transmission of donor-related bacterial infection through a transplanted heart.

This study describes a patient who had fulminant infectious myocarditis as a result of methicillin-resistant Staphylococcus aureus after receiving a heart transplant from an infected donor. There was complete concordance of typing results between donor and recipient strains that were different from the 20 isolates with which they were compared. Molecular epidemiologic study provided compelling evidence that a transplanted organ can transmit a bacterial infection from the donor to the recipient.

Adult↗
PubMed1996

[Usefulness of polymerase chain reaction for the diagnosis of Bazin erythema induratum].

BACKGROUND: Erythema induratum of Bazin (BEI), is included in the group of cutaneous granulomatous lobulillar panniculitis. The aethiopathogenic association between EI and tuberculosis can not rely on the clinicohistological features of these panniculitis and M. tuberculosis has never been isolated from BEI lesions. Detection of the mycobacterial DNA by PCR on cutaneous biopsy samples would allow to confirm this association. PATIENTS AND METHODS: Fourteen patients with clinical BEI were chosen retrospectively. Seventeen lesional biopsy samples were obtained, stained with the Kinyoun carbolfuchsin acid-fast technique and haematoxylin and eosin and tested by PCR. A fragment of the IS6110 insertion sequence specific of M. tuberculosis was amplified and confirmed by digestion with Sal I restriction endonuclease. The efficiency of the procedure, the presence of inhibitory substances and the preservation of DNA were checked by PCR of the beta-actin gene. RESULTS: M. tuberculosis DNA was detected in 12 of the 17 samples tested (70.5%) which corresponded to 10 of the 14 patients (71.4%). According to beta-actin PCR results, the rate of extracted DNA was inadequate on four of the five negative biopsies. CONCLUSIONS: The results of these series suggest the probable involvement of M. tuberculosis on the BEI pathogenesis and give support to the usefulness of the PCR in the diagnosis of this pathology concerning the need of specific treatment.

Adult↗
PubMed1996

Enterovirus persistence and myocardial damage detected by 111In-monoclonal antimyosin antibodies in patients with dilated cardiomyopathy.

BACKGROUND: Patients with dilated cardiomyopathy in whom enteroviruses in the myocardium are detected are more likely to die than those in whom no viruses have been demonstrated. The presence of enterovirus RNA in the myocardium at endomyocardial biopsy has been shown to be the strongest predictor of reduced survival. These results raise the question as to whether persistent virus might be responsible for continuing myocardial damage. Detection of myocardial cell damage is assessed using 111Indium-labelled monoclonal antimyosin antibodies. The present study was undertaken to address the question of whether the presence of myocardial cell damage by such antibodies in patients with dilated cardiomyopathy can be correlated with enterovirus persistence. PATIENTS AND METHODS: A series of 19 consecutive patients diagnosed as having chronic dilated cardiomyopathy who were referred for evaluation for heart transplantation were studied with 111Indium labelled monoclonal antimyosin antibodies. These patients and 10 controls were screened for enterovirus RNA sequences in endomyocardial biopsy tissue by hybridization with an enterovirus group-specific cDNA probe. RESULTS: Antimyosin uptake, indicative of myocardial cell damage, was observed in 16 of 19 patients (84%), with dilated cardiomyopathy, and enterovirus RNA sequences were detected in endomyocardial biopsies from four of these 16 patients (25%), but not in myocardium from the remaining three patients with a negative antimyosin scan, nor from any of 10 controls. CONCLUSIONS: Although these data do not establish a causal relationship between virus persistence in the myocardium and myocardial damage, the results obtained in the preliminary study support the hypothesis that enterovirus persistence is associated with continuing myocardial damage in patients with dilated cardiomyopathy.

Adult↗
PubMed1996

Molecular typing of Salmonella enterica serovar typhi.

The efficiencies of different tests for epidemiological markers--phage typing, ribotyping, IS200 typing, and pulsed-field gel electrophoresis (PFGE)--were evaluated for strains from sporadic cases of typhoid fever and a well-defined outbreak. Ribotyping and PFGE proved to be the most discriminating. Both detected two different patterns among outbreak-associated strains.

Bacterial Typing Techniques↗
PubMed1996

Diagnostic value of protected BAL in diagnosing pulmonary infections in immunocompromised patients.

STUDY OBJECTIVES: To assess the diagnostic utility of protected BAL (P-BAL) in respiratory infections in immunocompromised patients and to examine whether P-BAL alone could substitute the combined use of protected specimen brush (PSB) and BAL in such patients. PATIENTS AND STUDY DESIGN: Thirty-seven immunocompromised patients who underwent PSB, P-BAL, and BAL simultaneously for the diagnosis or exclusion of bacterial or nonbacterial opportunistic respiratory infections were studied prospectively. The P-BAL was performed through the inner catheter of a telescoping plugged catheter with 60 mL of saline solution. MAIN RESULTS: Thirteen (35%) cases of bacterial pneumonia were diagnosed. PSB obtained seven true-positive (TP) results, P-BAL obtained nine, and BAL obtained eight TP. Results of the three techniques were positive and concordant in 6 of the 13 cases. PSB remained free of contamination from oropharyngeal flora in all cases, P-BAL was contaminated twice, and BAL was contaminated in four cases. Opportunistic respiratory infections were diagnosed in 19 patients. P-BAL results were identical to those with BAL in all cases: 18 TP and 1 false-negative. The average volume of P-BAL fluid retrieved was 19 mL, sufficient for all microbiologic and cytologic processings. P-BAL was more time-consuming than both PSB and BAL procedures and was technically more complex. CONCLUSION: P-BAL alone can substitute the combined use of both PSB and BAL in immunocompromised patients and attains a higher sensitivity than PSB in diagnosing bacterial pneumonia. The combined strategy continues to be a good choice, but due to the high incidence of bacterial pneumonia in these patients, a highly efficient diagnostic procedure is required not only for nonbacterial opportunistic respiratory infections but also for bacterial pneumonia.

Adult↗
PubMed1996

[Usefulness of DR, PGRS, and spoligotyping in the typing of Mycobacterium tuberculosis. Comparison with IS6110].

BACKGROUND: To evaluate 4 markers (IS6110, DR, PGRS and spoligotyping) to differentiate the strains of Mycobacterium tuberculosis isolated in our surroundings, most specially in those which contain a reduced number of IS6110 copies. In addition, to confirm the identity of the strains that share the same IS6110 restriction-hybridization pattern. METHODS: We selected 37 strains from a previous study: 25 had a unique IS6110 pattern and 12 grouped in 3 clusters (8 strains with 11 bands, 2 with 17 bands and 2 which shared the same six-band pattern). The PGRS and DR-RFLPs were obtained by AluI restriction and synthetic oligonucleotides specific to these sequences. The polymorphism of the DR region spacers was analyzed by spoloigotyping. For the amplification of the spacers we used the DRa and DRb primers. Detection was done hybridizing the PCR products on a membrane in which 43 specific spacers had been previously immobilized. RESULTS: Twenty-three different PGRS patterns and 18 spolygotyping patterns were obtained from 25 strains with unique IS6110 pattern. Eight patterns resulted from the 10 strains studied by DR. The 8 strains which shared an 11-band pattern, as well as the 2 strains which shared a 17-band pattern, resulted identical by the other markers. However, 2 strains which shared a 6-band pattern were different by both PGRS and DR or spoligotyping. CONCLUSIONS: 1) IS6110 resulted the most discriminative marker of all. 2) The clonality of clusters with a low number of bands has to be confirmed with alternative markers.

Bacterial Typing Techniques↗
PubMed1996

[Clinical relevance of gram-negative bacteria having inducible chromosomic beta-lactamase at an intensive care unit].

BACKGROUND: The aim of the study was to determine the frequency of third-generation cephalosporins and aztreonam resistance in gram-negative bacteria with inducible chromosomal beta-lactamase (beta Lac-ind) after beta-lactam therapy in the medical-surgical intensive care unit (ICU) at a university-affiliated hospital. PATIENTS AND METHODS: We studied 34 infections in 29 patients admitted to the ICU. All were infected by strains with beta Lac-ind and all were treated with beta-lactam antibiotics. Susceptibility was determined by disc-diffusion. The beta-lactamase activity of those strains showing constitutive beta-lactamase overproduction were characterized by isoelectrofocusing. When this derepression occurred during the therapy, the strains were compared by genomic macrorestriction (PGFE). RESULTS: In 29 out of 34 infections the initial strains was susceptible. In 11 cases, the culture were not negativized in spite of their susceptible pattern. In 4 cases there was derepression during therapy. In 5 cases the initial strains were derepressed. The microorganisms isolated more frequently were Pseudomonas aeruginosa (22 cases) and Enterobacter cloacae (5 cases). The beta-lactamase activity detected correspond well with a betaLac-ind. In those cases with derepression during therapy, the initial susceptible strain and the resistant strain were identical by PGFE.

Adolescent↗
PubMed1996

[Hemorrhagic colitis caused by verotoxigenic Escherichia coli. Presentation of 9 cases].

OBJECTIVE: To describe the clinical and epidemiological characteristics of nine patients with enteritis caused by verocytotoxin-producing E. coli O157. PATIENTS AND METHODS: Clinical data of patients was collected retrospectively, the isolated strains were tested for verotoxin production (VT) using Vero cell culture line, and presence of VT1 and VT2 gene sequences was detected using amplification techniques (PCR), biotype was also determined using twelve biochemical tests, and genomic macrorestriction profile (PFGE). RESULTS: The patients' age ranged from 11 months to 70 years. The mean duration of diarrhea was 4.7 days. All patients but one had abdominal cramps, seven of nine reported hemorrhagic stools and six had fever. Three patients were affected of haematologycal neoplasia and two of them developed hemolytic-uremic syndrome as a complication. All strains produced VT2 and two of them also produced VT1. Epidemiological link between patients has not been established. Three different biotypes had been distinguished between the nine isolated strains. All but two had different macrorestriction profiles. DISCUSSION: The results obtained showed that clinical manifestations are rather inespecific, including fever (6/9 patients) and there is high association of severe complications. The heterogeneity in PFGE results obtained confirms that the cases are not related.

Adult↗
PubMed1996

Detection of Mycobacterium tuberculosis complex DNA by the polymerase chain reaction for rapid diagnosis of cutaneous tuberculosis.

We assessed the polymerase chain reaction (PCR) technique to detect Mycobacterium tuberculosis complex DNA in 48 paraffin-embedded specimens from 32 patients with different variants of cutaneous tuberculosis, and compared the results with those of culture. A 123 bp product of the IS6110 insertion sequence specific of M. tuberculosis complex was amplified and confirmed by digestion with SalI restriction endonuclease. The time required for the procedure was 3 days. Thirty-seven samples (77.1%) were positive for M. tuberculosis complex DNA. No false positive results were obtained in nine negative controls. Of the 20 specimens tested by PCR and culture, the frequency of positivity was 90% for DNA amplification and 65% for culture. In seven cases of lupus vulgaris, the figures were 100% and 57%, respectively. In the 11 specimens culture negative or not microbiologically tested and PCR negative, evidence for tuberculous infection was provided by the correlation of various relative and absolute criteria. These results show that PCR amplification of the IS6110 insertion fragment is a rapid and accurate means for the detection of M. tuberculosis complex DNA in paraffin-embedded skin biopsies from patients with cutaneous tuberculosis, especially in paucibacillary lesions.

Adolescent↗