Biomedical subjects

J García-de-Lomas

Publications and source records attributed to J García-de-Lomas.

At least 19 recordsLinked to original sources

PubMed2006

Etiological misidentification by routine biochemical tests of bacteremia caused by Gordonia terrae infection in the course of an episode of acute cholecystitis.

Gordonia terrae has been reported to be a rare cause of bacteremia. We report the first case of bacteremia associated with acute cholecystitis. Commercial biochemical testing was not able to identify the strain at the genus level, classifying it instead as Rhodococcus sp. Definitive identification was obtained by sequencing of the 16S rRNA gene.

Actinomycetales Infections↗

PubMed2003

Evolution of penicillin and erythromycin co-resistance in Streptococcus pneumoniae in Spain.

The temporal dynamics of penicillin and erythromycin co-resistance in Streptococcus pneumoniae based on two extensive multicentre Spanish surveillance SAUCE studies (1996-1997 and 1998-1999) is presented. Erythromycin resistance among penicillin non-susceptible isolates seems to have reached a limit as evidenced by a null increase between the two surveys, whereas it is growing among penicillin-susceptible pneumococci.

Drug Resistance, Bacterial↗

PubMed2002

Activities of six different quinolones against clinical respiratory isolates of Streptococcus pneumoniae with reduced susceptibility to ciprofloxacin in Spain.

Six quinolones were tested on 817 consecutive pneumococcal isolates for which ciprofloxacin MICs were high (> or =2 microg/ml); the isolates had been collected during two recent Spanish surveillance studies. For strains for which the ciprofloxacin MIC was >or =4 microg/ml, the MICs at which 90% of the isolates tested against gemifloxacin, moxifloxacin, gatifloxacin, sparfloxacin, levofloxacin, and ofloxacin were inhibited were 0.25, 1, 1, 1, 4 and 16 microg/ml, respectively, and the corresponding prevalences of resistance were 0, 1, 4.5, 9.5, 8.4 and 23%. The proportion of isolates for which the ciprofloxacin MIC is high has increased over time.

Anti-Infective Agents↗

PubMed2001

Antimicrobial susceptibilities of 1,730 Haemophilus influenzae respiratory tract isolates in Spain in 1998-1999.

A beta-lactamase prevalence of 23% was found among 1,730 Haemophilus influenzae isolates. Ampicillin susceptibility was 70%, and 12% of beta-lactamase-negative strains presented diminished susceptibility to ampicillin (BLNAR phenotype). Susceptibility of 90% was found for cefaclor and clarithromycin, whereas it was nearly 100% for cefotaxime, cefixime, azithromycin, and cefuroxime. Ciprofloxacin-resistant (0.1%) and beta-lactamase-positive amoxicillin/clavulanate-resistant (BLPACR) phenotypes (0.1%) are anecdotal so far.

Anti-Bacterial Agents↗

PubMed2001

Antimicrobial susceptibilities of 1,684 Streptococcus pneumoniae and 2,039 Streptococcus pyogenes isolates and their ecological relationships: results of a 1-year (1998-1999) multicenter surveillance study in Spain.

A nationwide multicenter susceptibility surveillance study which included 1,684 Streptococcus pneumoniae and 2,039 S. pyogenes isolates was carried out over 1 year in order to assess the current resistance patterns for the two most important gram-positive microorganisms responsible for community-acquired infections in Spain. Susceptibility testing was done by a broth microdilution method according to National Committee for Clinical Laboratory Standards M100-S10 interpretative criteria. For S. pneumoniae, the prevalences of highly resistant strains were 5% for amoxicillin and amoxicillin-clavulanic acid; 7% for cefotaxime; 22% for penicillin; 31% for cefuroxime; 35% for erythromycin, clarithromycin, and azithromycin; and 42% for cefaclor. For S. pyogenes, the prevalence of erythromycin resistance was 20%. Efflux was encountered in 90% of S. pyogenes and 5% of S. pneumoniae isolates that exhibited erythromycin resistance. Erythromycin resistance was associated with clarithromycin and azithromycin in both species, regardless of phenotype. Despite the different nature of the mechanisms of resistance, a positive correlation (r = 0.612) between the two species in the prevalence of erythromycin resistance was found in site-by-site comparisons, suggesting some kind of link with antibiotic consumption. Regarding ciprofloxacin, the MIC was >or=4 microg/ml for 7% of S. pneumoniae and 3.5% of S. pyogenes isolates. Ciprofloxacin resistance (MIC, >or=4 microg/ml) was significantly (P < 0.05) associated with macrolide resistance in both S. pyogenes and S. pneumoniae and with penicillin nonsusceptibility in S. pneumoniae.

Drug Prescriptions↗

PubMed2000

Seroepidemiology of Bordetella pertussis infections in the Spanish population: a cross-sectional study.

A study was conducted on a representative sample (n=4084) of the Spanish population to assess the prevalence of antibodies to pertussis toxin (PT) and filamentous hemagglutinin (FHA). A total of 1982 men and 2102 women aged 5-59 years were stratified by sex and age (5-12, 13-19, 20-29, 30-39, 40-49 and 50-59 years). Antibodies to PT were found in 46% samples and to FHA in 74% and increased with age (p<0.0001), ranging from 35% in the 5-12 year age group to 52% in the 50-59 year age group for anti-PT and from 65 to 80% for anti-FHA, respectively. As vaccine induced-immunity wanes over time, the observed age distribution of antibodies suggests that Bordetella pertussis infection is widespread in the Spanish population and that pertussis booster vaccination in adolescents and adults with the newly developed acellular vaccines, should be considered if it is deemed necessary to control the circulation of the organism.

Adhesins, Bacterial↗

PubMed2000

Streptococcus pneumoniae in community-acquired respiratory tract infections in Spain: the impact of serotype and geographical, seasonal and clinical factors on its susceptibility to the most commonly prescribed antibiotics. The Spanish Surveillance Group for Respiratory Pathogens.

Resistance of Streptococcus pneumoniae to antimicrobial agents shows geographical variation and also depends on serotype, patient age and sample origin. Factors affecting antibiotic resistance in S. pneumoniae were studied from results of a multicentre susceptibility study of 12 antimicrobial agents, carried out in 14 Spanish hospitals between May 1996 and April 1997. The most frequent serotypes were serotypes 6 (14.8%), 19 (11.8%), 23 (10.5%), 3 (9.9%), 9 (8.0%), 14 (8.0%), 15 (3.9%) and 11 (3.2%); 9.6% of isolates were not typeable. The remaining 25 serotypes constituted 20.2% of strains. Penicillin resistance was more prevalent in serotypes 14 (88%), 23 (66%), 9 (62%) and 6 (57%), whereas erythromycin resistance was more prevalent in serotypes 6 (68.5%), 15 (61.4%), 14 (49.5%), 19 (42.7%) and 23 (39.3%). Serotypes 6 and 19 were the serotypes most commonly isolated from both children and adults, although with different proportions (24.0% and 19.2% of isolates from children were serotype 6 and 19, respectively, with the corresponding figures for isolates from adults being 13.6% and 11.5%, respectively). The rates of resistance of pneumococcal strains to penicillin and cefuroxime were significantly higher in strains from children than in those from adults (resistance to penicillin, 50.4% in children and 37.0% in adults; resistance to cefuroxime, 62.4% in children and 45.6% in adults). There was significantly more resistance to erythromycin in middle ear isolates (48.9%) than in blood isolates (27%). The prevalence of resistance to beta-lactams showed a seasonal pattern, with higher rates in summer and winter, proportional to the magnitude of resistance. Susceptibility to macrolides did not vary seasonally. Our results stress the relative importance that geographical, temporal (seasonality), patient (sample type, origin, age group) and bacterium-related (serotype) factors have on the variations in susceptibility observed among different pneumococcal clinical isolates.

Adult↗

PubMed2000

A large percentage of the Spanish population under 30 years of age is not protected against hepatitis A.

A seroepidemiological study was conducted to assess the seroprevalence of hepatitis A (HAV) antibodies in the Spanish general population in 1992-93. A total of 2744 subjects (1337 men and 1437 women) in the 5-59 years age range were stratified by gender and age (5-12, 13-19, 20-29, 30-39, 40-49, 50-59 years). The presence of total anti-HAV antibodies was investigated using a commercial enzyme immunoassay. Fifty-five percent (95% CI: 53.5-57. 2%) of the subjects were positive for anti-HAV antibodies, the age-standardized anti-HAV prevalence being 65.4%. Prevalence of seropositive subjects increased with increasing age (chi(2) = 996, 17; P < 0.0001), being 11%, 25% and 54% for the 5-12, 13-19 and 20-29 age groups respectively. The results from this study showed a remarkable decline in seroprevalence rates among children, adolescents and young adults. The large number of susceptible subjects in these groups of the population has public health implications in a country with intermediate HAV prevalence.

Adolescent↗

PubMed1999

Low prevalence of diphtheria immunity in the Spanish population: results of a cross-sectional study.

A seroepidemiological study was conducted on a representative sample (n = 3944) of the Spanish population to assess the immune status to diphtheria. A total of 1907 men and 2037 women in the 5-59 years age range were stratified by sex and age (5-12, 13-19, 20-29, 30-39, 40-49, 50-59 years). Concentrations of toxin antibodies were measured using a commercial ELISA kit. Samples with titres > or = 0.1 IU/ml were considered to show full protection. Only 26% (95% CI: 25-28%) of the overall population studied was fully protected. The highest number of subjects with uncertain or no protection was found in the 20-39 age group (> 85%). The prevalence of fully protected subjects progressively declined from 51% for the 5-12 year age group, to 14% for the 30-39 year age group, whereas it increased to 20% and 35% for the 40-49 and the 50-59 year age groups, respectively (p < 0.0001). These results stress the need to intensify vaccination programs in adolescents and adults with periodic booster doses of diphtheria toxoid.

Adolescent↗

PubMed1999

Is sexual transmission an important pattern for herpes simplex type 2 virus seroconversion in the Spanish general population?

Herpes simplex type 2 (HSV-2) seroprevalence within a community is determined by sexual and perinatal transmission from mother to baby, the two main sources of virus shedding. A seroepidemiological study of HSV-2 was undertaken on a representative sample (n = 3974) of the Spanish population to assess indirectly the relative relevance of these two transmission routes. The sample comprised 1922 men and 2052 women in the age range 5-59 years, stratified by sex and age (5-12, 13-19, 20-29, 30-39, 40-49, and 50-59 years). Sera were screened for HSV-2 specific Ig G antibodies by an enzyme-linked immunoabsorbent assay based on recombinant glycoprotein G2 (gG2). The overall prevalence of antibodies to HSV-2 was 3.6% (95% CI: 3. 1-4.2%). Prevalence by gender did not differ: males (3.6%; 95% CI: 2. 8-4.6%) and females (3.6%; 95% CI: 2.8-4.5%). There were no significant differences between age groups with respect to seropositivity rates. Detection of HSV-2 antibodies was not associated with increasing age, as is expected for a sexually transmitted disease. The fact that seroprevalence rates among the different age groups did not differ suggests that the virus is not circulating in the general population and may be restricted to risk groups only. Similar positivity rates found in the group of females of childbearing age and in the youngest population indicate that perinatal viral shedding is the main source of HSV-2 seroconversion in the Spanish population.

Adolescent↗

PubMed1999

Whole cell lysate enzyme immunoassays vs. recombinant glycoprotein G2-based immunoassays for HSV-2 seroprevalence studies.

Seroepidemiology studies of herpes simplex virus type 2 (HSV-2) infections have been difficult to carry out because antibodies to HSV type 1 (HSV-1) show an extensive cross-reactivity with HSV-2 antigens. Many kits available currently are not entirely type specific for serodiagnosis of HSV-2 infections and therefore do not allow reliable discrimination of past exposure to these closely related alphaherpes viruses. Attempts to develop type-specific antigens have focused on the envelope glycoproteins, particularly glycoprotein G (gG). A cross-sectional study was carried out to examine the seroprevalence of antibodies to HSV-2 among healthy university students, using different methods: a whole cell lysate enzyme-linked immunosorbent assay (ELISA), two different ELISAs, and a newly developed immunoblot assay, the last three based on recombinant gG2. HSV-2 prevalence was 24 times higher with the whole cell lysate ELISA (31%; 95% confidence interval [CI]: 27-35%) than the ELISAs and the immunoblot assay based on recombinant gG2 (1.3%; 95% CI: 0.1-2.5%), thus showing the inaccuracy of commercial tests based on whole-antigen preparations for epidemiological studies. Laboratories should be cautious and ensure that commercial tests for HSV typing are based on type-specific glycoproteins.

Adolescent↗

PubMed1999

Is there an ecological relationship between rates of antibiotic resistance of species of the genus Streptococcus? The Spanish Surveillance Group for Respiratory Pathogens.

The relationship between resistance to antibiotics on the part of Streptococcus pneumoniae and Streptococcus pyogenes was studied by comparing different prevalences of resistance among hospitals obtained from a recent microbiological surveillance of community-acquired respiratory tract infections. A high correlation for erythromycin resistance was found between S. pneumoniae isolates from lower respiratory tract infections and S. pyogenes isolates collected from pharyngeal swabs.

Drug Resistance, Microbial↗

PubMed1998

A comparative study on the efficacy of the new quinolone alatrofloxacin in the treatment of experimental legionellosis in guinea pigs.

The in vivo efficacy of trovafloxacin, intraperitoneally administered as alatrofloxacin (CP-116,517), was assessed and compared with that of erythromycin, alone or in combination with rifampicin, in a model of Legionella pneumophila pneumonia in guinea pigs. Trovafloxacin (5 mg/kg administered as alatrofloxacin once daily for 7 days) gave a survival rate of 100% in infected animals. Clearance of bacteria and of bacteria-induced lesions from lungs was achieved by day 6 post-inoculation. The lungs of trovafloxacin-treated animals remained free of bacteria at day 28 post-challenge. Trovafloxacin proved as effective as erythromycin administered intraperitoneally, but was superior to erythromycin alone. or in combination with rifampicin, when given orally.

Administration, Oral↗

PubMed1997

Antimicrobial susceptibility of Streptococcus pneumoniae isolated from pediatric carriers in Spain.

The in vitro activity of several beta-lactam agents, macrolides, and cotrimoxazole was investigated against 53 Streptococcus pneumoniae isolates recovered from healthy children. The rates of resistance to penicillin or amoxicillin, cefaclor, and cefuroxime were 30%, 51%, and 37%, respectively. No cefotaxime-resistant isolates were found. Rates of resistance to erythromycin, clarithromycin, and cotrimoxazole were 22.6%, 13.2%, and 83%, respectively. Pneumococci with divergent antimicrobial susceptibility profiles (susceptible or moderately resistant vs. resistant isolates) coexisted in 32% samples, with divergencies more often involving beta-lactam agents and/or macrolides. In five of these samples, isolates belonged to different serotypes.

Adolescent↗

PubMed1997

New directions in diagnostics.

BACKGROUND: Infectious diseases are still a significant clinical problem in children, and accurate identification of the causal pathogen plays an important role in clinical management. The availability of an etiologic diagnosis enables the clinician to make appropriate therapeutic decisions and to avoid the indiscriminate use of antibiotics. The availability of a microbiologic diagnosis and the susceptibility profile of the pathogen allows the prompt initiation of suitable antibiotic treatment. However, the usefulness of current culture and identification methods is limited by the time needed and by their sensitivity and specificity. Also some microorganisms are difficult or impossible to grow in the laboratory. OBJECTIVES: To review the newer and more rapid diagnostic techniques that are becoming available and consider their application in the diagnosis of specific infections. DISCUSSION: Immunoassays have many advantages and it is hoped that new optical immunoassays will overcome the problems of poor sensitivity. Nucleic acid amplification techniques have enormous potential in the diagnosis of infectious diseases because of their high specificity and sensitivity and the speed with which the results can be obtained. However, there are still a number of difficulties that must be overcome before these methods can be widely adopted for routine testing. These techniques may be particularly relevant for the rapid diagnosis of streptococcal pharyngitis, where throat culture is slow and beset by a number of factors which reduce its accuracy. Polymerase chain reaction methods have been developed for many respiratory pathogens, including Mycoplasma pneumoniae, Chlamydia pneumoniae and Mycobacterium tuberculosis, and are likely to play an increasingly important part in diagnosis. In bacterial meningitis culture is still the gold standard and molecular techniques have not yet been developed to the point where they can be used in routine diagnosis. Nucleic acid techniques are likely to be very valuable in the diagnosis of streptococcal pharyngitis and viral central nervous system infections in the near future.

Bacterial Infections↗

PubMed1996

Relationship between outer membrane protein profiles and resistance to ceftazidime, imipenem, and ciprofloxacin in Pseudomonas aeruginosa isolates from bacteremic patients.

Outer membrane protein (OMP) profiles of 122 Pseudomonas aeruginosa isolates recovered from the blood of bacteremic patients were analyzed to relate alterations in the expression of OMPs with porin activity to resistance to imipenem, ceftazidime, and ciprofloxacin. Imipenem-resistant isolates lacked or expressed reduced amounts of porin OprD. In contrast, alterations of OMP profiles were absent in most ceftazidime-resistant isolates. Six of 12 ciprofloxacin-resistant isolates had normal OMP profiles. The remaining isolates showed alterations in the expression of either OprC, OprF, or OprD. In addition, imipenem- and ceftazidime-resistant isolates displayed a beta-lactamase activity compatible with that of a group 1 chromosomal cephalosporinase.

Anti-Infective Agents↗

PubMed1995

Rapid diagnosis of pleural tuberculosis by polymerase chain reaction.

We have investigated the use of polymerase chain reaction (PCR) for the rapid diagnosis of pleural tuberculosis. The study was composed of 21 patients with pleural tuberculosis, confirmed by culture or pleural biopsy, and 86 control subjects. The PCR assay was based on detecting a 123-bp DNA segment belonging to the insertion sequence IS6110, specific of Mycobacterium tuberculosis complex. In 21 patients diagnosed with pleural tuberculosis, Ziehl-Neelsen staining was positive in three (14%) (95% CI, 7 to 21%) and pleural fluid culture in 11 (52%) (95% CI, 43 to 61%). Pleural biopsy revealed granulomas with caseous necrosis in 72%, and the culture was positive in 67% of the patients. Adenosine deaminase activity determination was positive (> 45 IU/L) in 86% (95% CI, 79 to 93%). The sensitivity and specificity for PCR was 81% (95% CI, 74 to 88%) and 100% (95% CI, 95 to 100%), respectively. All culture-positive specimens were PCR positive. We conclude that PCR is a rapid, sensitive, and specific method for the diagnosis of pleural tuberculosis. However, further prospective studies are required to properly evaluate the yield of the technique.

Adolescent↗

PubMed1995

The utility of polymerase chain reaction (PCR) in the diagnosis of pulmonary tuberculosis.

A fragment of DNA of 123 bp belonging to insertion sequence IS6110, specific of Mycobacterium tuberculosis complex, was amplified by polymerase chain reaction (PCR) of respiratory samples, for the diagnosis of pulmonary tuberculosis. A total of 314 samples (286 sputum and 28 bronchoalveolar lavages) from 242 patients were evaluated by PCR, and the results were compared with the those obtained by acid-fast-stained smears, culture, and clinical diagnosis. Mycobacterium tuberculosis was detected by PCR in 102 of 105 patients with clinical diagnosis of pulmonary tuberculosis. All smear and culture-positive samples were PCR positive. The sensitivity of PCR, culture, and staining was 97%, 88%, and 65%, respectively, and the specificity was 100% in all cases. In ten patients with old residual lesions, but no active disease, M tuberculosis genome was detected by PCR. In our experience, PCR proved to be a useful method for the rapid diagnosis of pulmonary tuberculosis.

Adolescent↗