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P Coll

Publications and source records attributed to P Coll.

At least 91 records · Page 5Linked to original sources
PubMed1993

Incidence of listeriosis in Barcelona, Spain, in 1990. The Collaborative Study Group of Listeriosis of Barcelona.

A population-based register of cases of listeriosis admitted to acute-care hospitals has been established in Barcelona, Spain, in order to estimate the basal incidence of sporadic cases and to facilitate epidemiological surveillance of potential epidemics. Eleven acute-care hospitals reported all cases of listeriosis to a central unit following a standardized protocol. During 1990, 31 patients with listeriosis were identified, 18 of whom were residents of the city, resulting in an annual incidence of 10.95 cases per million inhabitants. Twelve of the 31 cases occurred in the period from July to September 1990, ten of them being community-acquired. The incidence of listeriosis was higher in elderly (> or = 65 years) and immunosuppressed persons. Forty-two percent of the cases were considered to be nosocomial infections. The overall mortality rate was 51.6%. The incidence of listeriosis in the present study is one of the highest reported in the literature. A high sensitivity of the reporting system with good case identification techniques, or demographic and environmental characteristics related to Listeria monocytogenes infection in our area, might be possible reasons for this geographic variation.

Adolescent↗
PubMed1993

Ultrastructural localization of major hydatid fluid antigens in brood capsules and protoscoleces of Echinococcus granulosus of human origin.

Monospecific rabbit antisera obtained through experimental immunization with previously purified proteins were used in the ultrastructural localization of two hydatid fluid antigens, in brood capsules and protoscoleces of Echinococcus granulosus of human origin. The antigen-antibody reaction was revealed by a colloidal gold based method. Reaction was evident in the connective region of the germinal membrane and in the parenchyma of the protoscoleces. Both antigen 5 and antigen B were located in the interstitial material between the parenchymal cells and precisely associated with disorganized areas. The brood capsule wall and the brood capsule contents, the tegument of the protoscoleces, the parenchymal cells, the muscle cells, the calcareous corpuscles and the hooks did not contain antigen 5 or antigen B. Label was not observed in the lumen of the collecting ducts or in the flame cells, although antigen 5 was evident in the periluminal cytoplasm. The origin of the antigens and their release are discussed.

Animals↗
PubMed1993

Detection of human papillomavirus 16 and 18 DNA in epithelial lesions of the lower genital tract by in situ hybridization and polymerase chain reaction: cervical scrapes are not substitutes for biopsies.

Human papillomavirus (HPV) types 16 and 18 in 66 women with histologically documented lesions of the genital tract and 64 control cohorts were investigated. The efficacies of in situ hybridization and polymerase chain reaction (PCR) in detecting HPV 16 and 18 DNA were analyzed. In order to assess the usefulness of replacing biopsies with cervical scrapes, the two samples were compared by PCR. The prevalence rates of HPV infection by PCR were 59.1 and 10.9% in patients and controls, respectively. PCR was three times more sensitive than in situ hybridization (52.6 versus 17.8%). However, the need to improve PCR sensitivity by subsequent dot blot hybridization reduced one of the main advantages of PCR, i.e., expeditious diagnosis. Cervical scrapes were less sensitive than biopsies (13.6 versus 53%), although with four (6.1%) patients with intraepithelial neoplasias, HPV DNA was identified only by means of cervical scraping. We conclude that obtaining biopsy specimens and cervical scraping are complementary sampling procedures.

Adolescent↗
PubMed1993

Infection of pulmonary artery catheters. Epidemiologic characteristics and multivariate analysis of risk factors.

Sixty-nine consecutive pulmonary artery catheters (PACs) were prospectively studied in a medical-surgical intensive care unit. Fifteen (21.7 percent) and two (2.9 percent) of the PACs were associated with colonization and bacteremia, respectively. These data represent an incidence of 4.98 and 0.66 episodes per 100 catheterization-days, respectively. Coagulase-negative staphylococci were the most common isolates. The source of the colonizing microorganism was the skin in 56 percent of cases, hubs in 28 percent, and unknown in 16 percent. From multivariate analysis, only more than 5 days of catheterization was significantly associated with a greater risk of colonization. Antimicrobial use was associated with negative cultures. The most useful method to diagnose colonization was the examination of both tip and intradermal segments. In addition, we suggest associate hub cultures when catheter-related bacteremia is suspected. These data may be useful in improving efficacy in the diagnosis and prevention of PAC-related infection.

Bacteremia↗
PubMed1993

Incidence of community-acquired pneumonia and Chlamydia pneumoniae infection: a prospective multicentre study.

This one year prospective multicentre study was designed to determine the incidence of community-acquired pneumonia in adults. It was carried out in primary health care centres and three reference hospitals, located in the 'Maresme' region (Barcelona, Spain) serving a population of 39,733 subjects over 13 years of age. Patients suspected of having contracted community-acquired pneumonia were visited by their family doctors and referred to the three reference hospitals for confirmation of the diagnosis. Patients attending the emergency services of these hospitals were also included. Urine and blood samples were obtained for culture, antigen detection, blood count, serological tests, blood gases and biochemical profile. The diagnosis of community-acquired pneumonia was made in 105 patients. Forty-six patients had an identifiable microbial etiology. Chlamydia pneumoniae was the most common pathogen (16 cases) followed by Streptococcus pneumoniae (13 cases) and Mycoplasma pneumoniae (8 cases). In conclusion; the annual incidence rate of community-acquired pneumonia in adults in this area was 2.6 cases per 1,000 inhabitants and Chlamydia pneumoniae was the most frequent causative pathogen.

Adolescent↗
PubMed1992

[Evaluation of two commercial kits for detection of Helicobacter pylori specific antibodies in patients undergoing gastroscopy. A seroprevalence study in an asymptomatic population].

BACKGROUND: We evaluate two different commercially available kits for detecting specific antibodies against Helicobacter pylori in a group of 48 patients with gastrointestinal symptoms that underwent an endoscopic procedure. We also study the seroprevalence of anti-H. pylori antibodies in asimptomatic individuals from our area. METHODS: Microbiologic and pathologic studies were performed in 48 gastric biopsies, in relation with antibodies detection using ELISA (Pylori stat test, Whittaker) and latex particles agglutination (Pyloriset, Orion). We also used ELISA tests for determining the seroprevalence of H. pylori antibodies in 139 asimptomatic individuals. RESULTS: Ninety-four percent of patients with peptic ulcer disease and 81% of patients without peptic ulcer disease but complaining of dyspepsia were infected by H. pylori. None of the patients with normal gastric mucosae was found to be infected. Sensitivity and specificity of ELISA test were 100% and 73%. Latex test sensitivity and specificity were 46% and 82%. The seroprevalence of antibodies among healthy individuals in our area increases with age (19% among children under 9 years of age) and reaches a peak at 40-49 years of age (84%), with a mean value of 60% in all ages' groups. CONCLUSIONS: There is a high correlation between Helicobacter pylori infection and gastric mucosa alterations. The ELISA test is best correlated with other laboratory data used for defining infection. The seroprevalence of H. pylori antibodies is also high, and therefore we recommend that the use of serologic diagnostic test must be highly selective.

Adolescent↗
PubMed1991

Echinococcus granulosus: antigen characterization by chemical treatment and enzymatic deglycosylation.

Parasite antigenic fractions obtained by biochemical purification of sheep hydatid fluid were subjected to enzymatic digestion. The relative mobilities of the 5 and B antigens, before and after treatment, were analyzed by polyacrylamide gel electrophoresis (SDS-PAGE) and Western blot. Antigenic fractions transferred to nitrocellulose were also treated with sodium metaperiodate and concanavalin A. The results indicate that antigen 5 contains a substantial amount of carbohydrates covalently linked to a polypeptide backbone, which strongly bind to concanavalin A and is removed by N-glycosidase F (PNGase F). Antigen 5 possesses complex N-linked oligosaccharides (PNGase F sensitive), without terminal N-acetyl-D-glucosamine residues (N-acetyl-D-glucosaminidase nonsensitive) and has no high-mannose oligosaccharides (endo-beta-N-acetylglucosaminidase H nonsensitive). In contrast, the antigen B of low molecular weight is not susceptible to either enzymatic digestions (PNGase F, Endo H, and N-acetyl-D-glucosaminidase) or sodium metaperiodate oxidation and it does not bind to concanavalin A. Polyclonal antibodies prepared against the two antigens reacted with the deglycosylated antigen 5 in Western blot. The dominant epitopes are, therefore, polypeptides, although the presence of carbohydrate epitopes in the native glycoproteins cannot be excluded.

Acetylglucosaminidase↗
PubMed1991

Immunochemical localization of major hydatid fluid antigens in protoscoleces and cysts of Echinococcus granulosus from human origin.

Monospecific rabbit antisera obtained through experimental immunization with previously purified proteins were used in the structural localization of two hydatid fluid antigens, antigen 5 and antigen B, in cyst membranes and protoscoleces of E. granulosus from human origin. The antigen-antibody reaction was revealed by an avidin-biotin-peroxidase technique. Antigen 5 was not evident in the laminated membrane of the cyst wall, but it was associated with the germinal membrane of the cyst wall and brood capsules. The parenchyma of invaginated and evaginated protoscoleces was heavily labelled. The tegument, the calcareous corpuscles, the suckers and the hooks did not contain antigen 5. Degenerated protoscoleces were also labelled. Antigen B localization was essentially identical to antigen 5, but degenerated protoscoleces were not recognized by anti-antigen B antiserum. Technical aspects and differences with previously published work are discussed.

Animals↗
PubMed1991

Laboratory diagnosis of catheter-related bacteremia.

Semiquantitative culture of the external surface of catheter tips has become the currently most used method to detect catheter colonisation and catheter-related bacteremia; however, this method may fail to detect significant colonisation of the internal lumen of catheters, and several quantitative methods have been described for this purpose. Although 15 and 1000 CFU are used to define positive catheters, the sensitivity and specificity are not yet well known, and the definitive cut-off level for a positive result remains to be established. We studied prospectively 91 intravascular catheter tips removed because a catheter-related infection was suspected. The result of external and internal cultures with different cut-off levels, alone or combined, were correlated with clinical data in 22 bacteremic episodes which occurred in these patients, 12 of which were catheter-related. The semiquantitative culture of the external surface alone with a cut-off level of 25 CFU provided the best means of detecting catheter-related bacteremia. This method has 100% sensitivity and 81.1% specificity. We conclude that semiquantitative culture technique of the catheter tip alone is sufficient and this method should be employed for diagnosing catheter-related bacteremia in unselected populations.

Bacteremia↗
PubMed1991

Evaluation of different catheter parts for identification of pulmonary artery catheter colonisation.

A prospective study was conducted over 18 months to evaluate the accuracy of the semiquantitative culture technique performed from different catheter parts for detection of catheter colonisation in critically ill patients with pulmonary artery catheters. Semiquantitative culture of the tip catheter segment alone detected 66% of catheter colonisations. Semiquantitative culture of the other intravascular catheter segments (atrial or intradermal) provided similar yield. A combination of intradermal and atrial or tip catheter segment cultures provided the best means of detecting catheter colonisation.

Bacteria↗
PubMed1991

[Detection of pneumococcal capsular polysaccharide antigen in urine by counterimmunoelectrophoresis. Technical features and correlation with serotype].

The effectiveness of CIE in detecting capsular polysaccharide antigen of pneumococci in urine is revised. Using CIE, we studied urine samples from 57 patients with systemic pneumococcal infections, proved bacteriologically by means of isolation of the microorganisms from sterile sites. We compare the usefulness of CIE with the microorganism isolation from organic products. We also determine the sensitivity gain after passive diffusion at 4 degrees C and bright blue Coomasie staining (CBB R-250). We correlate the CIE results with the serotype of isolated pneumococci. CIE was positive in 17 of all 35 pneumonia cases (48.6%), in 2 of all 5 bacteremias (40%), 4 of all 15 meningitis (26.7%) and in none of all two peritonitis. Direct urine examination was positive in 12 out of 23 patients with positive CIE (52.2%) and concentrated urine in 22 patients (95.6%). Passive diffusion at 4 degrees C and CBB R-250 stain increases the positive rate of the test. The correlation of serotype with our results is difficult due to the wide variety of serotypes identified. However, particular serotypes such (3, 4 or 8) had been identified with increased sensitivity. Global sensitivity of CIE in detecting capsular polysaccharide antigen in urine samples is not high enough (40.3%), even under the best circumstances. Antigen detection in urine is more sensitive than blood cultures, and therefore we believe that could be used in clinical microbiology laboratories until a more effective method is available.

Antigens, Bacterial↗
PubMed1991

[Value of studying the extraluminal and intraluminal surfaces in the detection of catheter colonization].

612 catheters have been prospectively investigated. In all of them, both the external and the internal surfaces were cultured, the former with the semiquantitative technique of Maki and the latter with the semiquantitative technique of Liñares. 102 of the 469 central venous catheters (22%), 21 of 70 catheters used for parenteral nutrition (30%), and 19 of the 73 arterial catheters (26%) were positive with one or both techniques. The external surface was positive in 95% of central venous catheters, in 90% of the parenteral nutrition catheters, and in 95% of the arterial catheters, whereas the internal surface was positive in only 59%, 62% and 42%, respectively. The routine study of the internal surface of the catheters does not appear as justified. In our opinion, the microbiological study of catheters should be individualized depending on the relative importance of the skin or the connections in a particular catheter type. The quantitative study of the intraluminal surface should only be carried out in those catheters where connections represent a significant pathogenetical route. These catheters constitute only a small proportion of those that we receive for culture in the Microbiology Laboratory; therefore, this approach represents a considerable simplification of our daily routine.

Bacteria↗