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P Coll

Publications and source records attributed to P Coll.

At least 73 records · Page 4Linked to original sources
PubMed1996

[Disseminated Mycobacterium genavense infection in patients with HIV infection. Description of 5 cases and review of the literature].

BACKGROUND: Five cases of disseminated infection by Mycobacterium genavense in patients with HIV infection are reported with a review of the literature. MATERIAL AND METHODS: A description of the clinical, epidemiologic and therapeutic characteristics of five cases are presented. The initial isolation of the microorganism was performed in Bactec 13A from blood and bone marrow aspirates. Subcultures were made in different media and the growth characteristics evaluated. Sensitivity to NAP was determined by radiometric techniques and gas chromatography allowed a possible identification. Definitive identification was based on PCR amplification of the gene which codifies the 65kDa protein and the posterior restriction of the amplified fragments by using BstEII and HaeIII. RESULTS: All five patients were males with HIV infection and a lymphocyte count of less than 25 cells/mm3 with an non-specific clinical picture similar to that produced by M. avium complex (MAC). Empiric antiMAC treatment was administered in four of the patients with good clinical response. All five strains were sensitive to NAP. The greatest growth rate was obtained in the subcultures with acid pH in liquid medium. Gas chromatography was very similar to that of M. simiae. Amplification of the gene which codifies the 65 kDa protein and posterior restriction with BstEII resulted in 2 fragments of 325 and 125 bp, while restriction with HaeIII resulted in two fragments of 140 and 105 bp. CONCLUSIONS: Mycobacterium genavense represents 9% of the disseminated infections by mycobacteria in AIDS patients. The clinical manifestations, empiric treatment and response is similar to that of infection by M. avium complex. Growth is favored by acid pH in liquid medium. Susceptibility to NAP leads to possible identification which should be confirmed by molecular techniques.

AIDS-Related Opportunistic Infections↗
PubMed1995

Organic chemistry in Titan's atmosphere: new data from laboratory simulations at low temperature.

Many experiments have already been carried out to simulate organic chemistry on Titan, the largest satellite of Saturn. They can provide fruitful information on the nature of minor organic constituents likely to be present in Titan's atmosphere, both in gas and aerosol phases. Indeed, all the organic compounds but one already detected in Titan's atmosphere have been identified in simulation experiments. The exception, C4N2, as well as other compounds expected in Titan from theoretical modeling, such as other N-organics, and polyynes, first of all C6H2, have never been detected in experimental simulation thus far. All these compounds are thermally unstable, and the temperature conditions used during the simulation experiments were not appropriate. We have recently started a new program of simulation experiments with temperature conditions close to that of Titan's environment. It also uses dedicated analytical techniques and procedures compatible with the analysis of organics only stable at low temperatures, as well solid products of low stability in the presence of O2 and H2O. Spark discharge of N2-CH4 gas mixtures was carried out at low temperature in the range 100-150 K. Products were analysed by FTIR, GC and GC-MS techniques. GC-peaks were identified by their mass spectrum, and, in most cases, by comparison of the retention time and mass spectrum with standard ones. We report here the first detection in Titan simulation experiments of C6H2 and HC5N. Their abundance is a few percent relative to C4H2 and HC3N, respectively. Preliminary data on the solid products indicate an elemental composition corresponding to (H11C11N)n. These results open new prospects in the modeling of Titan's haze making.

Acetylene↗
PubMed1995

Treatment of pulmonary disease caused by Mycobacterium kansasii: results of 18 vs 12 months' chemotherapy.

SETTING: Chest Clinic, Sant Pau Hospital, Barcelona, Spain. OBJECTIVE: To assess the therapeutic response of pulmonary disease due to Mycobacterium kansasii to 12 and 18 months of chemotherapy. DESIGN: 28 patients with criteria of pulmonary disease caused by M. kansasii not associated with HIV-infection were identified in our department in the period 1985-91 (24 male, 4 female, mean age 56 +/- 12 years). 14 patients were treated with rifampicin-isoniazid-ethambutol daily for 12 months (ethambutol only for the first 6 months), and 14 with the same regimen for 18 months. The follow-up after treatment was 12-30 months. RESULTS: All patients showed improvement of radiographic manifestation of disease and sputum conversion (mean time: 4.5 +/- 2 months). The adverse drug effects were minimal. No failures were detected, and only one patient (3.5%), in the group of 12-month chemotherapy, relapsed after finishing the treatment. CONCLUSIONS: Our findings suggest that pulmonary disease due to M. kansasii has an effective response to 12-month chemotherapy regimen and that it is not necessary to prolong the administration of ethambutol for more than 6 months.

Adult↗
PubMed1995

Hemorrhagic stroke as a complication of bacterial meningitis in adults: report of three cases and review.

We describe three adults who had hemorrhagic strokes during the acute phase of bacterial meningitis (BM). We also report the results of a literature review and a review of the charts of 296 adults treated at our hospital for acute BM. The diagnosis of hemorrhagic stroke was made based on the results of cerebral computed tomography (CT) for two of 92 patients with BM who had CT performed and by means of lumbar puncture and a postmortem study in one other case. Two patients died of cerebral bleeding. Although the frequency of hemorrhagic stroke was only 2.1% among adults with acute BM, it is a major determinant of prognosis for such patients.

Adult↗
PubMed1995

[Epidemic outbreak of shigellosis following water intake].

BACKGROUND: To describe the clinical, epidemiologic and microbiologic characteristics of an outbreak of shigellosis. METHODS: Twenty-six patients affected by shigellosis were studied. Upon identification of the outbreak, a questionnaire was carried out in relatives to determine the attack-rate. Studies of the isolated strains included biotype, antibiotype, and in 8 selected strains, plasmid and ribotyping profile. RESULTS: From September 23 to October 21 1991, 26 patients (42% males, 54% under the age of 14 years), 23 of whom drunk water from two nearby fountains were attended for acute gastroenteritis and positive stool culture with isolation of Shigella sonnei strains with identical biochemical pattern and sensitivity. Only 2 required hospital admission and all recovered well. Forty-five percent of the 80 individuals who had drunk water from the fountains were affected. The attack-rate was higher in children (67%) than in adults (27%) (p < 0.001). The plasmid profile was identical in the strains studied. The only discriminative endonuclease used for the ribotyping was Sal I, which allowed the strains corresponding to the outbreak to be differentiated from those used as controls. CONCLUSIONS: An outbreak of shigellosis due to water ingestion is herein reported. The usefulness of plasmid profile as an epidemiologic marker of Shigella is confirmed. Only one of the four enzymes used for the ribotyping was discriminative. A greater susceptibility to infection was observed in children.

Adolescent↗
PubMed1995

Escherichia coli capsular polysaccharide and spontaneous bacterial peritonitis in cirrhosis.

Spontaneous bacterial peritonitis (SBP) is a frequent and severe complication of cirrhosis. Escherichia coli is the most frequent bacterium isolated in this condition. The presence of capsular antigens, mainly the K1 capsular polysaccharide, has been associated with invasiveness in E coli infections. Capsular serotypes of E coli causing SBP were determined in 37 cirrhotic patients. Twenty-seven strains were encapsulated (72.9%), 9 of them (24.3%) with K1 capsular polysaccharide, and 10 were nonencapsulated. Patients with encapsulated E coli showed a significantly higher incidence (92.5% vs. 50%; P < .01) and number of complications per patient (1.9 +/- 1.1 vs. 0.8 +/- 1.0; P < .01) than patients with nonencapsulated strains. Although mortality was higher in patients with encapsulated strains (44.4% vs. 20%), the difference did not reach statistical significance. Considering patients infected by encapsulated strains, the incidence of complications and mortality were similar in patients with or without K1 strains. These data suggest that the presence of encapsulated strains could have a prognostic significance in SBP caused by E coli in cirrhotic patients.

Aged↗
PubMed1994

[Application of molecular epidemiology techniques in the study of food poisoning caused by Staphylococcus aureus].

BACKGROUND: The use of molecular epidemiology techniques has provided better knowledge as to the clonal organization of bacterian populations and thus allows better follow up of epidemics. An alimentary toxiinfection in a Barcelona school produced by Staphylococcus aureus was analyzed by the combination of epidemiologic, phenotype and genotype markers with the aim of determining the source of the alimentary contamination. METHODS: Nine strains of Staphylococcus aureus isolated in 6 food manipulators and 3 patients were studied with the following markers: biotype, antibiotype, phagotype, plasmid profile, polymorphism of the size of the restriction fragments of total DNA and ribotype. RESULTS: Epidemiologic study of the strains analyzed showed that both the phenotype markers and the plasmid profile are thecniques of little discriminatory value. The only clearly discriminatory technique used was ribotyping which defined 3 clones in the 9 strains of Staphylococcus aureus studied. CONCLUSIONS: Molecular study of isolated strains of Staphylococcus aureus was able to identify the causal origin of the alimentary toxiinfection in one of the 6 food manipulators studied.

Bacterial Typing Techniques↗
PubMed1994

[Clinico-epidemiologic study of human listeriosis in Barcelona (1990-1991)].

BACKGROUND: The aim of this study was to determine the incidence of human listeriosis in Barcelona in addition to its clinical form of presentation, seasonability, risk groups and evolution. METHODS: A prospective study of the cases of listeriosis registered in the city of Barcelona, Spain (population of 1,643,542 inhabitants) over the period from January 1, 1990 to December 31, 1991 was carried out. RESULTS: Fifty-five cases were reviewed with a global rate of incidence of listeriosis of 9.4 per one million inhabitants per year with predominance being observed in the summer months (39% in 1990, 42% in 1991). Ninety-one percent of the cases were observed in non pregnant adults, with 86% of the patients being immunosuppressed. Nosocomial listeriosis, diagnosed in 23 patients (42%), was predominant in the group with immunosuppressive treatment (p = 0.0005). The main site of isolation was blood in 45 cases (82%), in the form of primary listeriosis (p < 0.0005). Global mortality was 49%, being greater in the group of patients with nosocomial infection (p = 0.01) and with primary bacteremia (p < 0.001). No patients without known risk factors or pertaining to the perinatal group have died. CONCLUSIONS: The use of an active system of registration of listeriosis facilitates better knowledge of its incidence, distribution and infection pattern thus allowing the early detection of epidemic outbreaks with the aim of controlling such an infection, given the social implications and morbidity of this disease.

Adolescent↗
PubMed1994

[Fiberoptic bronchoscope disinfection with glutaraldehyde phenolate in 1:8 solution].

We evaluated the efficacy of phenolated glutaraldehyde in a 1:8 solution for the disinfection of bronchofibroscopes that were highly contaminated with Serratia marcescens and Pseudomonas aeruginosa. An Olympus BF-P10 bronchofibroscope was contaminated with artificial samples containing one of the aforementioned microorganisms in concentrations nearing 10(8) colony forming units per milliliter (cfu/ml). The instruments were then washed with soap and water and submerged in a 1:8 solution of phenolated glutaraldehyde. Samples were taken for culturing after contamination, after washing, and after 10, 15 and 30 min in the disinfectant solution. The level of cfu/ml in the cultures was measured and the definition of failure-to-disinfect was a finding of > or = 1 cfu/ml after each experimental procedure. Twenty procedures, 10 for each microorganism, were carried out. Washing of the bronchofibroscope afforded significant elimination of microorganisms and no colony growth was observed in cultures after 10 min submersion in phenolated glutaraldehyde. We conclude that immersion in a 1:8 solution of phenolated glutaraldehyde after careful washing is a valid way to disinfect bronchofibroscopes that are highly contaminated with S. marcescens and P. aeruginosa.

Bronchoscopes↗
PubMed1994

A comparative study of ribotyping and arbitrarily primed polymerase chain reaction for investigation of hospital outbreaks of Acinetobacter baumannii infection.

Arbitrarily primed polymerase chain reaction (AP-PCR) and ribotyping were compared in an investigation of an outbreak of Acinetobacter baumannii infections. Twenty-five clinical isolates shown previously by other criteria to belong to two different groups, and nine randomly selected A. baumannii clinical isolates from other hospitals were investigated. Among the strains analysed, nine different EcoRI rRNA gene restriction pattern fingerprints were observed. While similarity was detected between strains of the same group, these fingerprints differed clearly between the two A. baumannii groups defined in the outbreak. Two of the nine strains selected randomly had the same ribotype as those strains involved in the outbreak, whereas the remaining seven strains each had a different ribotype. When the strains were tested by AP-PCR with 0.25, 0.5 or 1 microM of M13 forward primer, 10 different profiles were obtained. However, 11 profiles were observed if two different primer concentrations (0.25 and 1 microM) were used. It was concluded that ribotyping and AP-PCR exhibited a similar discriminatory power, although AP-PCR had the additional advantages of speed and simplicity.

Acinetobacter↗
PubMed1994

[Utility of the direct culture examination (Ziehl-Neelsen) using the Bactec system for the presumptive identification of Mycobacterium tuberculosis complex, Mycobacterium avium complex, Mycobacterium xenopi, and Mycobacterium kansasii].

BACKGROUND: The usefulness of the microscopic examination of Bactec 12B and 13A growth medium as a method for the possible identification of M. tuberculosis complex, M. avium complex, M. xenopi, and M. kansasii was performed out to guide the selection of different genetic identification probes and, in the case of M. xenopi, the selection of the temperature of subcultures incubation. METHODS: Upon detection of an index of growth greater than 100 in Bactec tubes, staining was performed by the Ziehl-Neelsen technique. On the basis of the morphology observed, the possible identification was performed by genetic probes. Subcultures were used for definitive identification. RESULTS: Three hundred forty-four positive samples were studied by radiometric technique. A total of 190 strains were identified as M. tuberculosis, 88 strains as M. avium-intracellulare (MAI), 33 strains as M. xenopi, 14 strains as M. kansasii and 19 strains were identified as: M. gordonae (10), unpigmented rapid growth microbacteria (7), and M. simiae (2). Sensitivity, specificity, positive predictive value, and negative predictive value were 97.9%, 95.4%, 96.4%, and 97.3%, respectively for M. tuberculosis complex, 84.0%, 99.2%, 97.3% 94.7% for M. avium complex; 63.6%, 98.3%, 80.7%, 96.2% for M. xenopi; 35.7%, 98.1%, 45.5% 97.2% for M. kansasii. CONCLUSIONS: The morphology of M. tuberculosis complex examined in the radiometric system in useful to differentiate this species from other microbacteria (MOTT), allowing the selection of specific probe used. Within the MOTT, M. avium complex also has morphological characteristics which are useful for its differentiation, the morphology usually described for the remaining species was frequently not observed.

Bacteriological Techniques↗