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N Sopena

Publications and source records attributed to N Sopena.

26 records · Page 2Linked to original sources
PubMed1997

[Impact of control measures on the course of an outbreak of methicillin-resistant Staphylococcus aureus].

BACKGROUND: Outbreaks of nosocomial infection by methicillin resistent Staphylococcus aureus (MRSA) are a problem in many hospitals with the control measures to be adopted being controversial. An outbreak of MRSA in a 550-bed university hospital is herein described and the impact of the adopted control measures on the evolution of the epidemic in the general hospitalization area (GHA) was analyzed. PATIENTS AND METHODS: The adopted control measures in the GHA were: microbiologic surveillance, cutaneous isolation measures, treatment of nasal carrier, and the early discharge of the cases. Hand washing was reinforced and a study of carriers was carried out on detection of sporadic cases (not related to the ICU). A molecular study of 70 strains of MRSA was performed with analysis of total plasmids, plasmid restriction pattern and chromosomic DNA analysis by pulsed field gel electrophoresis (PFGE). RESULTS: From December 1990 to December 1993, 273 cases of MRSA were reported. One hundred seventy-two cases originated in the ICU and 101 cases in the GHA (sporadic cases). The incidence of MRSA in 1991-1993 was 13.6, 14.3, and 6.6% in the ICU and 0.17, 0.36, and 0.15% in the GHA, respectively. Molecular study of MRSA isolates (1991 and 1992) demonstrated two plasmid and two chromosomic patterns. The latter had a similarity coefficient > 0.90, probably belonging to the same "clone". CONCLUSIONS: Despite the control measures adopted in the GHA the outbreak of MRSA originated in the ICU thereafter extending to the GHA. The rates of colonization detected, however, remained stable during the 3 years studied. On the other hand, the observation of a single "clone", responsible for the epidemic, suggest that most of the sporadic cases were autoctonous and due to failure in fulfillment of the established norms.

Cross Infection↗
PubMed1997

Comparison of radioimmunoassay and enzyme immunoassay kits for detection of Legionella pneumophila serogroup 1 antigen in both concentrated and nonconcentrated urine samples.

We evaluated a commercial enzyme immunoassay (EIA) kit for detection of Legionella pneumophila serogroup 1 soluble antigen by comparing it to radioimmunoassay (RIA), using both concentrated and nonconcentrated urine samples. The sensitivity of EIA was 67.4% in nonconcentrated urine samples and 82.6% in concentrated urine samples. The sensitivity of RIA was 60.9% and 84.8% in nonconcentrated and concentrated urine samples, respectively. Our study indicates that the sensitivity and specificity of EIA are comparable to those of RIA, and that concentrating the antigen by selective ultrafiltration increases sensitivity for both EIA and RIA, with no significant decrease in specificity.

Adult↗
PubMed1996

Detection of Legionella pneumophila serogroup 1 antigen in nonconcentrated urine and urine concentrated by selective ultrafiltration.

We evaluated a commercially available radioimmunoassay technique for detecting the soluble antigen of Legionella pneumophila serogroup 1 using concentrated and nonconcentrated urine. Concentration was achieved by selective ultrafiltration. The sensitivity of the technique was 60.9% for nonconcentrated urine and 80.4% for concentrated samples, with 100% specificity in both cases.

Antigens, Bacterial↗
PubMed1996

[Invasive Streptococcus agalactiae infections at a general university hospital over a 10-year period].

BACKGROUND: Streptococcus agalactiae is a known causal agent of neonatal meningitis, sepsis and puerperal infections. The incidence of invasive infections caused by Streptococcus agalactiae has increased in recent years in non gestating adults: in the elderly, patients receiving prolonged steroid treatment or those with chronic immunosuppressive diseases. The clinical and epidemiological characteristics and risk factors associated to invasive infections caused by S. agalactiae were analyzed. METHOD: A retrospective study was undertaken in patients with invasive disease by S. agalactiae attended in the Hospital Universitari Germans Trias i Pujol in Badalona (Barcelona), Spain, from 1983 to 1993. RESULTS: S. agalactiae was isolated in 51 patients including 13 (25%) neonates. Three patients presented invasive puerperal infection. Thirty-five adult patients with a mean age of 62 years presented invasive disease. Infection involved bacteremia in 26 (74.2%) patients. S. agalactiae was isolated in the ascitic fluid of 4 patients with liver cirrhosis with spontaneous bacterial peritonitis (one with bacteriemia) and in the peritoneal exudate of two patients with peritonitis secondary to intestinal perforation. Of 5 patients with septic arthritis, 3 involved bacteremia. Two patients presented empyema by S. agalactiae. Mortality was 28%, being directly related with infection in 4 cases (7.8%). CONCLUSIONS: Without taking pregnant women into account, 68% of the cases of invasive infections by S. agalactiae were observed in adults with associated base disease, with liver cirrhosis, neoplasms and diabetes mellitus being the most frequent. Advanced age was also found to be an important predisposing factor.

Adult↗
PubMed1995

Nosocomial and community-acquired Legionella pneumonia: clinical comparative analysis.

Previous reports have suggested that nosocomial and community Legionella pneumonia cases are similar. However, community and hospital characteristics, such as aquatic environment, antibiotic pressure (usage) and populations, are quite different, leading to the suspicion that Legionella infection may differ in the two settings. Univariate and multivariate analyses were performed to compare demographic data, risk factors, clinical, radiological and outcome data between 125 nosocomial and 33 community-acquired cases of Legionella pneumophila infection. Patients in the nosocomially acquired Legionella pneumonia (NALP) group were older than those in the community-acquired Legionella pneumonia (CALP) group. Univariate analysis showed that smoking habit, cough, thoracic pain, and extrapulmonary manifestations were more prevalent in the CALP group, whilst chronic lung disease and cancer were more prevalent in the NALP group. Moreover, patients in the NALP group were more likely to have received oxygen and corticosteroid therapy and also to have altered creatinine values than patients in the CALP group, whilst more patients in the latter group had altered alanine amino-transferase values. However, multivariate analysis failed to confirm most of these differences. Smoking habit and blood creatinine levels were the only variables remaining significant. In conclusion, demographic, clinical, laboratory, radiological and outcome data in nosocomial and community-acquired Legionella pneumonia are quite similar.

Adult↗
PubMed1994

Molecular epidemiology for local outbreaks of methicillin resistant Staphylococcus aureus (MRSA). The need for several methods.

Subtyping isolates may be useful for epidemiological studies of methicillin-resistant-Staphylococcus aureus (MRSA) outbreaks. Among subtyping methods, DNA-based techniques have been applied very effectively for this purpose. An outbreak of MRSA infections took place in one hospital in Barcelona early during 1991. From the beginning of the outbreak to December 92, 70 MRSA isolates from different patients and sources were collected. All strains were evaluated by restriction endonuclease analysis of plasmid DNA (REAP) and macrorestriction endonuclease analysis of genomic DNA using Sma I and pulsed-field-gel-electrophoresis (PFGE). Plasmid screening and REAP using Hind III demonstrated two plasmid subtypes: subtype A showing a large plasmid, and subtype B showing the same large plasmid plus a smaller one. Subtypes A and B corresponded to the more recent and older isolates, respectively, suggesting the loss of the small plasmid during the epidemic. PFGE using Sma I displayed two closely related profiles (PFGE subtype A and A'; CS = 0.90). These subtypes were different from those subtypes exhibited from 4 methicillin-susceptible-Staphylococcus aureus (MSSA) isolates from the same hospital and from 2 epidemiologically unrelated MRSA isolates. Almost all isolates showing PFGE subtype A preceded those isolates showing PFGE subtype A'. This fact and the similarity between both subtypes suggested minor chromosomal DNA rearrangement during the outbreak from a unique strain. While PFGE using Sma I is a useful tool in evaluation of clonal dissemination, our data suggest epidemic or local outbreaks may need several methods to best delineate the source and spread of MRSA strains. The reproducibility and discriminatory power of REAP makes it a useful adjunct in this context.

Anti-Bacterial Agents↗