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J García de Lomas

Publications and source records attributed to J García de Lomas.

At least 19 recordsLinked to original sources

Antimicrobial susceptibility of 1,422 Haemophilus influenzae isolates from respiratory tract infections in Spain. Results of a 1-year (1996-97) multicenter surveillance study. Spanish Surveillance Group for Respiratory Pathogens.

A Haemophilus influenzae multicenter antimicrobial susceptibility surveillance was carried out. An overall beta-lactamase production rate of 25.7% was found, with significant differences between hospitals ranging between 7.9 and 47.9%. Presumable intrinsic resistance was found in 4.6% of strains. No differences in susceptibility were observed between beta-lactamase positive and beta-lactamase negative strains for all antibiotics, except for penicillin, amoxicillin and cefaclor. A higher prevalence of resistance was found for clarithromycin vs azithromycin (22.6 vs 0.7%). Differences in all these factors make surveillance essential as a guideline for empiric treatment in community-acquired respiratory tract infections.

Drug Resistance, Microbial↗

Antimicrobial resistance of 1,113 Streptococcus pneumoniae isolates from patients with respiratory tract infections in Spain: results of a 1-year (1996-1997) multicenter surveillance study. The Spanish Surveillance Group for Respiratory Pathogens.

A nationwide susceptibility surveillance of 1,113 Streptococcus pneumoniae isolates was carried out and found the following percentages of resistance: cefuroxime, 46%; penicillin, 37%; macrolides, 33%; aminopenicillins, 24%; cefotaxime, 13%; and ceftriaxone, 8%. A significant (P < 0.05) seasonality pattern for beta-lactam antibiotics was observed. Resistance to macrolides was higher (P < 0.05) in middle-ear samples. Higher percentages of resistance to cefuroxime and macrolides were observed among penicillin-intermediate and -resistant strains, whereas high frequencies of resistance to aminopenicillins and expanded-spectrum cephalosporins were observed only among penicillin-resistant strains.

Cefuroxime↗

[Sensitivity of group A beta-hemolytic Streptococcus isolated from pediatric pharyngotonsillitis to erythromycin and clarithromycin: a primary care multicenter study].

BACKGROUND: The recent increase in the prevalence of macrolide-resistant group A beta-haemolytic Streptococcus (BHSGA) strains reported in some areas in Spain and several neighboring countries underscores the need to perform a periodic surveillance, with the adequate methodology, of the level of its susceptibility to these antimicrobials which are frequently used in our country for the treatment of acute streptococcal pharingotonsillitis and respiratory tract infections. PATIENTS AND METHODS: The susceptibility of 293 isolates of BHSGA to the macrolides erythromycin and clarithromycin was evaluated by the broth microdilution procedure recommended by the NCCLS (1997). The isolates were prospectively obtained from children with acute pharyngotonsillitis (n = 757) who were seen at primary care centers in ten Spanish cities. RESULTS: An overall prevalence of 8.9 and 7.8% erythromycin- and clarithromycin-resistant BHSGA isolates was respectively found. The percentage of resistant isolates varied considerably among the different cities subjected to study (0-33%). Overall, the intrinsic activity of clarithromycin (MIC50 and MIC90 of 0.007 and 0.25 mg/ml, respectively) was slightly higher than that of erythromycin (MIC50 and MIC90 of 0.015 and 0.5 mg/ml, respectively). All strains studied were uniformly susceptible to penicillin. CONCLUSIONS: Macrolide antibiotics, erythromycin and clarithromycin, continue to be highly active against BHSGA. The mean level of resistant strains found in Spain from community acquired infections and recovered prospectively is comparable to that of our neighboring countries.

Adolescent↗

[Penetration of meropenem in gram-negative bacilli. Differences in activity with imipenem].

The outer membrane of gramnegative bacteria cell-wall contain channels formed by proteins known as porins, which facilitate the penetration of molecules into the cell. Imipenem and meropenem possess an important intrinsic activity against most gramnegative bacteria due to their high affinity for the penicillin-binding proteins PBP-2 and/or PBP-3. Meropenem is slightly more active against certain species of Enterobacteriaceae, Pseudomonas aeruginosa and nonfermenters bacilli. In this sense the differences in the activity between the two carbapenems may be attributable to differences in their affinity for PBPs, differences in their resistance to beta-lactamases hydrolysis, or to the differences in the capacity to employ certain porin channels. OprF is the main porin channel involved in the beta-lactam penetration of bacteria, though OprC and OprD2 may also contribute to the penetration of carbapenems into P. aeruginosa. However, evidences suggest that although impenem requires the presence of OprD2, meropenem may use other pathways for penetration. In Escherichia coli both carbapenems use ompF and ompC, and no specific porin channels have been detected. Only in the case of Enterobacter cloacae may exceptions exists among Enterobacteriaceae.

Bacterial Outer Membrane Proteins↗

[Applications of the polymerase chain reaction (PCR) to the diagnosis of central nervous system infections].

The utility of polymerase chain reaction (PCR) is described for the diagnosis in three patients suffering from central nervous system infections, tuberculous meningitis, herpetic encephalitis and cerebral toxoplasmosis. PCR was performed in the cerebrospinal fluid after processing the specimen by two methods, proteinase K digestion and phenol extraction of DNA. Amplification was realized using primers previously described that amplify specific DNA fragments of each microorganisms (insertion sequence IS6110 of Mycobacterium tuberculosis, B1 gene of Toxoplasma gondii, and DNA polymerase gene of Herpes simplex virus). In all three cases, PCR was positive after amplification of the specimen extracted with proteinase K, as well as when a complete DNA extraction with phenol was realized. In all cases a band of amplified products was observed in agarose gels. In conclusion, in all three patients described, PCR would had allowed the diagnosis in seven hours, and PCR should be consider a rapid sensitive and relatively simple method.

AIDS-Related Opportunistic Infections↗

Multicentre comparative study on the antibacterial activity of FK-037, a new parenteral cephalosporin.

The in vitro antibacterial activity of FK-037, a new parenteral cephalosporin structurally related to cefpirome and cefepime, was compared with that of cefotaxime, ceftazidime, aztreonam, cefpirome, cefepime, imipenem and meropenem against 1,837 clinical isolates obtained from three Spanish hospitals. FK-037 inhibited 90% of Enterobacteriaceae isolates at < or = 0.25 microgram/ml, with the exception of Enterobacter aerogenes (MIC90 1 microgram/ml), Enterobacter cloacae and Citrobacter freundii (MIC90 8 micrograms/ml). In cefotaxime- and ceftazidime-resistant Klebsiella pneumoniae strains producing SHV-2 and SHV-6 beta-lactamases, the activity of FK-037, cefpirome and cefepime was similar (MIC range 0.25-32 micrograms/ml). In Enterobacteriaceae strains hyper-producing chromosomally inducible beta-lactamases, FK-037 (MIC90 range, 0.25-8 micrograms/ml) was 8- to 16-fold more active than cefotaxime and ceftazidime but two- to eightfold less active than cefpirome and cefepime. FK-037 and cefpirome were twofold more active than ceftazidime and cefepime against Pseudomonas aeruginosa isolates, with MIC90 values of 16 micrograms/ml. The activity of FK-037, cefpirome and cefepime was two- to eightfold lower in ceftazidime-resistant derepressed Pseudomonas aeruginosa mutants. FK-037 (MIC range, 0.12-2 micrograms/ml) and the other beta-lactam agents tested were active against methicillin-susceptible staphylococci; however, only cefpirome and, particularly, FK-037 (MIC90 of 32 micrograms/ml) displayed some activity against methicillin-resistant strains. In penicillin-susceptible, -intermediate and -resistant Streptococcus pneumoniae isolates, the MIC90s of FK-037 were 0.03, 0.5 and 1 microgram/ml, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Aztreonam↗

[Tuberculosis and human immunodeficiency virus infection. A prospective study of 215 patients].

We analyze the cases of 215 adult patients affected from tuberculosis (TB) and infection due to human immunodeficiency virus (HIV) in the study period from December 6th, 1986 to January 31st of 1992. Disease affected specially the group of drug addict patients (DAP) with a 74.88%, followed by paid plasma donors (PPD) from our city with a 12.09%. Sexual transmission was the route of contamination with the HIV in 16 cases. In five cases atypical mycobacteria were detected. First-line anti-tuberculostatics drugs activity against Mycobacterium tuberculosis was excellent. A total of 17 cases with toxicity to any of these drugs were described. TB was located in the lung in 108 cases (50.23%), in 74 cases out of the lung (34.41%) and in 33 cases there was intrapulmonary as well as extrapulmonary affectation (15.34%). TB was diagnosed at the same time that a disease which met AIDS criteria in 13.49% of cases, TB was diagnosed first in 32.55% of cases, and AIDS was diagnosed before TB in only 7.91% of cases. Fever was the predominant symptom (88.84%), together with toxic status at admittance (80.47%) and deteriorated immune situation with lymphocytes count decrease (mean 1240/mm) and CD4 (mean value 134.5/mm) together with a mean raised IgA (492.85 mg/dl). Thorax radiography was normal in 34.88%. In 33 of these patients TB was localized in the lung, in 27.91% primary radiologic types were observed while in 31.16% reactivation types. In 51 cases (23.72%) tuberculosis was detected in patients (DAP) who were forwarded from the penitentiary system.(ABSTRACT TRUNCATED AT 250 WORDS)

AIDS-Related Opportunistic Infections↗

[Use of DNA amplification to diagnose cytomegalovirus in HIV seropositive patients].

BACKGROUND: Cytomegalovirus (CMV) infection is common among HIV seropositive patients, being difficult to diagnose because it requires cell cultures not available in all hospitals. DNA amplification is being applied for diagnosis of infectious diseases with an increase in sensitivity and specificity with respect to previous laboratory methods. METHODS: Polymerase chain reaction (PCR) has been used in comparison with culture isolation, early antigen detection to diagnose CMV infection in 22 HIV infected patients, that suffered from symptoms compatible with CMV infection at the present time, and in other 5 patients suffering from Kaposi sarcoma. PCR was done with primer for CMV IE genomic region. The amplified sequences were detected after hybridization with a gamma-P-32 labelled probe, followed by electrophoresis in a 5% polyacrylamide gel and autoradiography. RESULTS: The PCR allows to detect CMV genome in cases in which other tests are negatives, in blood as well as in urine, included those patients suffering only from febrile symptoms or with other associated pathogen. CONCLUSIONS: PCR is a sensitive method to detect CMV, although it does not establish the responsibility of CMV in HIV infected patients.

Base Sequence↗

[The mycoplasmas isolated from respiratory specimens].

BACKGROUND: Mycoplasma pneumoniae is the species that is considered pathogen for respiratory tract. Other species, M. hominis and U. urealyticum, have been isolated from respiratory specimens and its aetiological relation with respiratory infections is not clear. METHODS: In this study, mycoplasma from respiratory specimens have been isolated from HIV infected patients, patients suffering from chronic bronchitis and patients with respiratory infections without any underlying disease, using SP-4 media and being identified with glucose fermentation test, guinea pig blood cells adsorption, tetrazolium reduction, urea test, arginine test, and antigenic study by an immunoassay on the colonies grown on SP-4 solid medium. RESULTS: M. hominis has been the species most frequent isolated, mainly from patients without any underlying disease and from HIV infected patients, and less frequently from patients suffering from chronic bronchitis, the differences between both groups being significative. Other Mycoplasma, no identified at he species level, have been isolated although without any significative differences. In only one case U. urealyticum has been isolated. CONCLUSIONS: No M. pneumoniae isolation was obtained.

Bacteriological Techniques↗