PubMed Health⌕ Search

Biomedical subjects

L Matas

Publications and source records attributed to L Matas.

At least 19 recordsLinked to original sources
PubMed2005

Rapid detection of pneumococcal antigen in serum samples for diagnosing pneumococcal pneumonia.

OBJECTIVES: The aim of the study is to assess the usefulness of C polysaccharide and polysaccharide capsular antigen detection by immunochromatography (ICT) and enzyme immunoassay (EIA), respectively, in serum samples for diagnosing pneumococcal pneumonia. METHODS: Adult patients included in the study were classified in the following groups: In group 1 we studied 101 serum samples from patients with pneumonia due to Streptococcus pneumoniae. In 53 cases the pneumonia was bacteremic. The second group contained 113 serum samples from patients with no pneumococcal pneumonia. Group 3 was made up of 40 serum samples from healthy subjects with no clinical or radiological signs of pneumonia. RESULTS: Using ICT, antigen was detected in 50% of patients with pneumococcal pneumonia, in 64.3 and 40.9% of patients with bacteremic and non-bacteremic pneumococcal pneumonia, respectively. Using EIA, antigens were detected in 35.8% of patients with pneumococcal pneumonia, in 45 and 22.2% of patients with bacteremic and non-bacteremic pneumococcal pneumonia, respectively. CONCLUSIONS: In conclusion, the sensitivity of the tests is low. However, in special situations, where obtaining large volume of urine is difficult, they could be a complementary method in the rapid diagnosis of pneumococcal pneumonia.

Adult↗
PubMed2005

Mycobactericidal and tuberculocidal activity of Korsolex AF, an amine detergent/disinfectant product.

The mycobactericidal and tuberculocidal activities of Korsolex AF against Mycobacterium tuberculosis, Mycobacterium avium-Mycobacterium intracellulare (MAI), Mycobacterium kansasii and Mycobacterium chelonae were determined using quantitative suspension and carrier tests. The effects of organic load and hard water were also considered. A clinical isolate of MAI was the most resistant of the four test organisms. A 2% solution had good mycobactericidal and tuberculocidal activities after 30 min of exposure. Although further evaluation using European standard tests is necessary, we conclude that Korsolex AF appears to be a promising product for the disinfection of hospital instruments contaminated with mycobacteria.

Amines↗
PubMed2005

Clinical usefulness of total hepatitis C virus core antigen quantification to monitor the response to treatment with peginterferon alpha-2a plus ribavirin*.

SUMMARY: Early virological response may predict outcome following treatment with peginterferon alpha-2a and ribavirin in patients chronically infected with hepatitis C virus (HCV). As total HCV core antigen may constitute an alternative direct marker to HCV RNA for assessing the levels of viraemia in such patients, we evaluated the correlation between HCV core antigen and HCV RNA, and whether HCV core antigen at baseline, 4 and 12 weeks after treatment could predict sustained virological response (SVR) to combined therapy, in comparison with HCV RNA. A total of 290 serum samples from 58 previously treatment naïve chronic HCV patients were examined for HCV core antigen and HCV-RNA by means of quantitative HCV RNA when receiving combination therapy for the first time. SVR was significantly associated with basal HCV core antigen but not with HCV RNA. There was a good correlation between HCV core antigen and HCV RNA (r(2) = 0.781). The negative predictive value of HCV core antigen testing in predicting nonresponse at weeks 4 and 12 were 75 and 100%, and for undetectable or a 2-log drop in HCV RNA were 69.6 and 75% respectively. HCV core antigen detection is quick, and easy to perform alternative to HCV RNA, and could be used as a marker of HCV viraemia for monitoring the progress of therapy.

Antiviral Agents↗
PubMed2005

[Histoplasmosis in a renal transplant patient].

The case of a Spanish kidney transplant patient who developed disseminated histoplasmosis approximately one year and a half after transplantation without having previously visited or travelled to endemic areas of histoplasmosis is presented. To our knowledge this is the first case of this disease in a kidney transplant patient in Spain without epidemiologic antecedent. The study of anti-histoplasm antibodies by complement fixation of the donor and recipient did not safely clarify the mechanism of contagion.

Histoplasmosis↗
PubMed2004

Evaluation of a commercial enzyme immunoassay for HIV screening in urine.

A cross-sectional study was conducted to evaluate the utility of a commercial enzyme immunoassay (EIA) as a screening test for detecting HIV-1 antibody in urine in a population at risk for HIV infection in Catalonia, Spain. Paired urine and serum samples were collected consecutively from 99 patients who attended two drug-dependency treatment centres and 151 patients who attended a sexually transmitted diseases (STD) clinic in Barcelona. Antibodies against HIV in urine samples were detected using the Calypte HIV-1 Urine EIA (Calypte Biomedical Corporation, Berkeley, CA, USA) and confirmed by urine-based Western blot (WB) analysis. Sera were analysed using Bioelisa HIV-1+2 EIA (Biokit Laboratories, Barcelona, Spain), and the results were verified using serum-based WB analysis. Results of both urine and serum testing were available for 246 of 250 participants. For 52 individuals the results of both urine and serum testing were positive and for five the results were discordant (2 with urine-negative/serum-positive results and 3 with urine-positive/serum-negative results). The respective sensitivity and specificity values obtained for the urine EIA were 100% and 96.2% for intravenous drug users (IDUs) and 80% and 99.3% for persons attending the STD clinic. According to the 1997 UNAIDS/WHO strategy I recommendations, these values are acceptable for surveillance purposes, particularly in populations with a high prevalence of HIV infection.

Cross-Sectional Studies↗
PubMed2003

Disseminated varicella infection in adult renal allograft recipients: role of mycophenolate mofetil.

Disseminated varicella zoster virus (VZV) infection is a rare complication after renal transplantation in adults. We report 4 cases diagnosed in our transplant patients. One of which was a primary infection (chicken pox) with multivisceral involvement (hepatitis, pneumonitis, myocarditis, and disseminated intravascular coagulation). The other 3 patients VZV-seropositive before transplantation suffered from disseminated zoster. No immunosuppressive drug was significantly associated with a higher risk of disseminated VZV infection. However, from our experience, we believe that mycophenolate mofetil (MMF), plays a part in the clinical presentation of the disease. Early treatment with high doses of acyclovir is fundamental in infection control. It is essential to perform a pretransplantation serological VZV study on all patients.

Acyclovir↗
PubMed2003

In-vitro evaluation of Perasafe compared with 2% alkaline glutaraldehyde against Mycobacterium spp.

Quantitative suspension and carrier tests were used to compare the activity of Perasafe and Cidex against Mycobacterium tuberculosis, Mycobacterium avium-intracellulare, Mycobacterium fortuitum, and Mycobacterium chelonae. The interference of an organic load, and of hard water was also considered. Both agents achieved reductions exceeding 10(5)-fold within 20 and 30 min for all the strains tested. Perasafe is thus mycobactericidal and a viable alternative to Cidex for intermediate or high-level disinfection.

Cross Infection↗
PubMed2003

In-use evaluation of Perasafe compared with Cidex in fibreoptic bronchoscope disinfection.

The mycobactericidal activity of Perasafe (0.26% peracetic acid) was compared with that of Cidex (2% alkaline glutaraldehyde) by an in-use test. Fibreoptic bronchoscopes were artificially contaminated with Mycobacterium tuberculosis or Mycobacterium avium-intracellulare in sputum and, after manual pre-cleaning with a neutral soap, 10 and 20 min disinfection periods were tested. Perasafe was as effective as Cidex, thus requiring a 10 min disinfection period against M. tuberculosis and 20 min against M. avium-intracellulare. The results demonstrate that Perasafe is an effective disinfectant for use in reprocessing fibreoptic bronchoscopes.

Bronchoscopes↗
PubMed2003

Assessment of Acinetobacter baumannii susceptibility to antiseptics and disinfectants.

Disinfection and antisepsis are of primary importance in controlling outbreaks of Acinetobacter baumannii, a nosocomial pathogen that frequently shows multiple antibiotic resistance. In this study we assessed the susceptibility of nine A. baumannii strains isolated during a sustained intensive care unit outbreak, to several antiseptics and disinfectants based on European Standards. While the tested strains showed diverse antibiotic resistance patterns, they were equally sensitive to the biocides assessed in vitro. We observed neither evidence of development of resistance to biocides over time, nor a correlation between resistance to antibiotics and a decreased susceptibility to antiseptics or disinfectants.

Acinetobacter Infections↗
PubMed2003

Evaluation of two different cell lysis methods for releasing mycobacterial nucleic acids in the INNO-LiPA mycobacteria test.

The INNO-LiPA Mycobacteria Test (Innogenetics, N.V., Belgium) is a PCR-based reverse hybridization assay for the simultaneous identification of several mycobacterial species. We evaluated two simplified lysis methods for mycobacterial DNA release for application in the INNO-LiPA Mycobacteria Test. The two methods were based on either (i) heat treatment or (ii) sonication. Both methods were performed directly on 45 positive liquid cultures (MB-BacT, BioMérieux, Marcy l'Etoile, France) containing 17 different mycobacterial species. These two simple lysis procedures demonstrated similar effectiveness (100%) to that recommended by the manufacturer. They also significantly shortened the time required for mycobacterial DNA release.

Bacterial Typing Techniques↗
PubMed2003

Usefulness of urinary antigen detection by an immunochromatographic test for diagnosis of pneumococcal pneumonia in children.

We evaluated an immunochromatographic assay detecting pneumococcal antigen in urine samples from children diagnosed with pneumococcal pneumonia. The sensitivity and specificity of the immunochromatographic test with nonconcentrated urine (NCU) were 86.7 and 62.9%, respectively; with concentrated urine (CU), they were 100 and 11.7%, respectively. Pneumococcal antigen was also detected in 42.5% of NCU and 87.1% of CU samples from nasopharyngeal carriers. This is a nonspecific test for the diagnosis of pneumococcal pneumonia in children, particularly the very young.

Adolescent↗
PubMed2003

Utility of an in-house mycobacteriophage-based assay for rapid detection of rifampin resistance in Mycobacterium tuberculosis clinical isolates.

A rapid in-house mycobacteriophage-based assay to identify multidrug resistance by detecting the rifampin susceptibility of Mycobacterium tuberculosis in a microtiter plate format was evaluated. The sensitivity, specificity, and overall accuracy of the assay were 100%. This test is rapid to perform and suitable for widespread implementation.

Antibiotics, Antitubercular↗
PubMed2003

Contribution of the initial features of systemic lupus erythematosus to the clinical evolution and survival of a cohort of Mediterranean patients.

BACKGROUND: Systemic lupus erythematosus has a wide spectrum of immunological and clinical manifestations. Its course is characterised by exacerbations which may result in mortality or morbidity to vital organs/systems. OBJECTIVE: To determine clear and early prognostic markers to avoid further complications. METHODS: 245 adult patients diagnosed between January 1978 and March 2001 were studied. Clinical manifestations and laboratory findings both at onset and during the clinical course were collected. The number, type, and severity of the flares were also noted. Statistical analyses between disease features at onset, subsequent flares, and mortality were performed. RESULTS: 239 patients entered the study. Their mean age at onset was 30 years. The mean time between onset and diagnosis was 36 months and the mean evolution time was 114 months. 205 patients developed 915 flares; 205 (22.4%) of these flares were major flares, and affected 110 patients. Cardiac, neurological, or renal affection at onset were associated with a higher probability of developing cardiac (p=0.022), neurological (p<0.001), and renal (p<0.001) exacerbations, respectively, during the evolution. Lupus anticoagulant (LA) and anticardiolipin antibodies (aCL) were predictors of stroke (aCL, p=0.000; LA, p=0.001). Age at diagnosis (p=0.003) and valvular disease at onset (p=0.008) were independent predictors of low survival. CONCLUSIONS: Renal, cardiac, or neurological involvement and the presence of LA or aCL positivity at onset were predictors of renal, cardiac, or neurological flares, respectively. Age and valvular involvement at onset were found to be independent adverse outcome predictors for low survival.

Adult↗
PubMed2002

Factors related to persistence of Legionella urinary antigen excretion in patients with legionnaires' disease.

The aim of this prospective study was to compare patient characteristics, clinical data, and evolution of Legionella pneumophila pneumonia according to the duration of Legionella urinary antigen excretion. Urine samples from 61 patients with Legionella pneumonia diagnosed by detection of urinary antigen were obtained periodically until urinary antigen could no longer be detected. Cases were divided into two groups based on the duration of urinary antigen excretion: group I (46 patients, <60 days) and group II (15 patients, >or=60 days). Groups were compared for patient characteristics, clinical data, and evolution of pneumonia. Antigen excretion >or=60 days was observed significantly more frequently in immunosuppressed patients ( P=0.001) in whom the time to apyrexia was >72 h ( P=0.002), although only the time to apyrexia remained significant on multivariate analysis ( P=0.006). In conclusion, the duration of Legionella urinary antigen excretion was <60 days in most patients but was longer in immunosuppressed patients with a longer time to defervescence of fever.

Adult↗
PubMed2002

Evaluation of the VITAL (bioMérieux) automated blood culture system using blind subculture.

OBJECTIVE: This study was performed to determine the ability of the VITAL system to detect and allow recovery of microorganisms that are difficult to grow, such as Brucella spp., yeasts, or anaerobes, as well as to determine the need for blind subcultures after the incubation period. METHODS: A prospective evaluation of the system was performed, and 8247 blood culture bottles were processed. The standard was blind subculture from all the bottles after 5 days of incubation. RESULTS: There were 3.2% false-positive and 0.6% false-negative results (72% of clinical importance). The system sensitivity for yeasts was 41%. The mean time for detection of Neisseria meningitidis was 31.9 +/- 2.8 h, for Brucella spp. 119.7 +/- 2 h, and for yeast 51.5 +/- 27.8 h. CONCLUSIONS: The VITAL system poses has serious difficulties in the detection of N. meningitidis, Brucella spp., yeast and methicillin- and aminoglycoside-resistant Staphylococcus aureus (MARSA). The low system sensitivity for yeast detection makes the blind subculture necessary after the incubation period.

Anaerobiosis↗
PubMed2001

Rapid detection of several mycobacterial species using a polymerase chain reaction reverse hybridisation assay.

The ability of a polymerase-chain-reaction-based technique combined with a reverse hybridisation line-probe assay to detect and identify eight of the most clinically significant mycobacterial species directly from cultures in liquid medium was evaluated. The line-probe assay allows simultaneous identification of eight different mycobacterial species. Ninety-seven mycobacterial strains belonging to 22 different species were evaluated. All strains were previously inoculated into MB/BacT bottles (Organon Teknika, USA). The sensitivity and specificity of the test when applied on positive MB/BacT liquid cultures containing isolates from mycobacterial species included as specific probes on the line-probe assay strip was 100% and 100%, respectively. These results further support the potential clinical usefulness of this technique in the diagnosis of mycobacterial infections.

Bacterial Typing Techniques↗
PubMed2001

Usefulness of adding multiplex nested-polymerase chain reaction assay of cerebrospinal fluid samples to routine diagnostic testing for herpesvirus encephalitis.

The present study was conducted to assess the usefulness of adding the multiplex nested-polymerase chain reaction assay of cerebrospinal fluid samples to routine diagnostic testing for herpesvirus encephalitis and to monitor the efficacy of therapy. Cerebrospinal fluid samples from 45 patients with presumed herpesvirus encephalitis were tested for herpes simplex virus, varicella-zoster virus, cytomegalovirus, human herpesvirus 6, and Epstein-Barr virus. Ten of the 45 patients were positive for a virus using the polymerase chain reaction assay: herpes simplex virus (n=5), Epstein-Barr virus (n=3), and herpes simplex virus plus the Epstein-Barr virus (n=2). Cerebrospinal fluid from two patients who had undergone acyclovir therapy gave negative results. Analysis of cerebrospinal fluid by multiplex polymerase chain reaction can be useful for establishing an accurate diagnosis and as a marker of the efficacy of therapy.

Adult↗