Group B streptococci causing neonatal infections in barcelona are a stable clonal population: 18-year surveillance.

We analyzed 212 group B streptococci (GBS) from newborns with invasive infections in the area of Barcelona, Spain, between 1992 and 2009, with the aim of documenting changes in the prevalences of serotypes, antimicrobial resistance, and genetic lineages and evaluating their associations with either early-onset disease (EOD) or late-onset disease (LOD). Serotypes III (n = 118) and Ia (n = 47) together accounted for nearly 78% of the isolates. All isolates carried an alpha or alpha-like protein gene, and specific associations between genes and serotypes, such as serotype Ib and bca, serotype II and bca, serotype III and rib, and serotype V and alp3, reflected the presence of particular genetic lineages. Macrolide resistance (14.2%) was significantly associated with serotype V. Pulsed-field gel electrophoresis (PFGE) clustering was an excellent predictor of serotype and antibiotic resistance. The combination of PFGE and multilocus sequence typing revealed a large number of genetically distinct lineages. Still, specific lineages were dominant in our collection, particularly the serotype III/ST17/rib lineage, which had enhanced potential to cause LOD. Serotype Ia was concentrated in a single PFGE cluster composed of two genetic lineages: ST23/eps and ST24/bca. The ST24/bca sublineage of serotype Ia, which is found infrequently elsewhere, may be emerging as an important cause of neonatal invasive infections in the Mediterranean region. In spite of the introduction of prophylaxis, resulting in a pronounced decline in the frequency of EOD, the study revealed a remarkably stable clonal structure of GBS causing neonatal infections in Barcelona over a period of 18 years.

Characterisation of invasive pneumococcal isolates in Catalan children up to 5 years of age, 1989-2000.

Ninety-six Streptococcus pneumoniae strains isolated between January 1989 and December 2000 from usually sterile sites of children aged < 5 years of age were included in the study. Resistance to penicillin (38.6% intermediate, 10.4% high-level), cefotaxime (20.8%), tetracycline (41.7%), chloramphenicol (33.3%) and erythromycin (27.1%), as well as serogroup/type, were related to age and pathology. Strains from children aged < 2 years showed the highest penicillin resistance rate. Resistance to penicillin, tetracycline, chloramphenicol and erythromycin was the most common pattern (18.8% of strains). Most isolates (80.2%) belonged to serogroups/types included in the heptavalent conjugate vaccine.

[Helicobacter pylori infections: antigen detection in stool samples]. / Infecciones por Helicobacter pylori: detección de antígeno en muestras fecales.

BACKGROUND: The aim of this study is to evaluate a new diagnostic test to detect Helicobacter pylori antigen in stool samples (HpSA), and compare the results with those obtained by standard techniques (rapid urease test,culture, histological examination of gastric biopsy specimens,13C-urea breath test and serology), in a paediatric population with gastrointestinal symptomatology. PATIENTS AND METHODS: Sixty patients with dyspeptic symptoms (37 females and 23 males;mean age 10.9 years) attending the Gastroenterology Service were included in the study. Exclusion criterium was previous treatment with proton pump inhibitors, bismuth compounds or antibiotics. Rapid urease test, culture and histologic study of gastric biopsies,13C-urea breath test and serology, as well as HpSA, were performed to all patients. RESULTS: Forty seven patients were considered infected by H.pylori on the basis of bacterium isolation and 13C-urea breath test positivity. HpSAwas detected in 45 of the 47 H.pylori positive patients(95.7%). There were no HpSA false positive. CONCLUSION: Our results show that this new test is highly sensitive (95%) and specific(100%) for detection of H. pylori infection. It has some advantages over other non invasive techniques: it is easy to perform,requires no blood samples and its cost is lower than that of 13C-urea breath test.

Neisseria meningitidis: evolution of penicillin resistance and phenotype in a children's hospital in Barcelona, Spain.

UNLABELLED: Neisseria meningitidis is the most prevalent micro-organism involved in paediatric bacterial meningitis in the Barcelona area in children over 3 mo of age and it is an important cause of morbidity and mortality in Spain. A total of 498 strains of N. meningitidis, obtained between the years 1986 and 1997 from children with sepsis and/or meningitis, were characterized according to their serogroup and penicillin resistance; their distribution in serotypes and subtypes was studied from 1990. A decreasing tendency in the number of annual isolates was observed in this period. Most isolates belonged to serogroups B (403 strains) and C (77 strains). Serogroup C accounted for 1.8% of the strains in 1986 and 57.1% in 1997. The most prevalent phenotype between 1990 and 1996 was B:4:P1.15. but C:2b:P1.2,5 was the most prevalent in 1997. Overall penicillin-resistance rates ranged from 9.1% in 1986 (when a non-susceptible strain was isolated for the first time in the Hospital Sant Joan de Déu, Barcelona, Spain) to 71.4% in 1997, and it was more common among strains belonging to serogroup C (52% of resistant strains) than to serogroup B (22.1 % of resistant strains). The penicillin-resistance level was low, MIC always < or = 0.5 microg/ml. The present increase in N. meningitidis group C isolates, mainly C:2b:P1.2,5, and the availability of preventive measures for this highly pathological and resistant phenotype, argues strongly for the establishment of an epidemiological monitoring system. Detection of penicillin resistance should be standardized worldwide in order to unify data from all laboratories. CONCLUSION: A shift between serogroups B and C is observed in Barcelona from 1986 to 1997, as well as a rapid distribution of decreased penicillin susceptibility.

[Evaluation of a simple rapid polymerase chain reaction (PCR) technique for the diagnosis of Helicobacter pylori infection in childhood]. / Evaluación de una técnica de reacción en cadena de la polimerasa (PCR) rápida y sencilla para el diagnóstico de la infección por Helicobacter pylori en la infancia.

BACKGROUND: The purpose of this study was to evaluate the use of polymerase chain reaction (PCR) applied to the diagnosis Helicobacter pylori infection in the pediatric population, by means of a rapid and simple method of extraction and posterior detection by a colorimetric hybridation of amplified H. pylori DNA. METHODS: Fifty three gastric biopsies, obtained through upper gastrointestinal endoscopy from 53 patients with gastric pathology (45 recidivant abdominal pain and eight hematemesis), were processed from october 1995 to july 1996. Three non invasive tests were performed: detection of IgG by (Cobas) Core Anti-H. pylori EIA (Roche), breath test with 13C-urea and PCR of dental plaque, as well as four invasive ones: histologic study, culture into selective (Pylori Agar, bioMérieux) and non selective media (Columbia Agar with 5% sheep blood, bioMérieux), test of rapid urease and PCR of gastric biopsies. A 20% solution of Chelex 100 resin (DNA Extraction Reagen, Perkin Elmer) was used for DNA extraction, amplification was performed from gen ureA (Clayton, 1992) and amplified DNA was detected by colorimetric hybridation (PCR ELISA, Boehringer, Mannheim). Duration of the PCR process was: extraction 25 min, amplification two hours and detection three hours. RESULTS: Results of culture and PCR from gastric biopsies agreed in 84.3% of cases (27 positives, 16 negatives and two not determined). Two samples were positive by culture and negative by PCR, and were considered as PCR false negatives due to positivity of three or more other tests. Six samples were negative by culture and positive by PCR, being considered as culture false negatives due to positivity of three or more other tests. Sensitivity of PCR and culture was 94.2 and 82.8%. Specificity was 100% for both tests. None of the dental plaque samples was positive. CONCLUSIONS: When invasive techniques are to be done for microbiologic diagnose of H. pylori, PCR increases the confirmation rate of infection; the present procedure enables daily routine work due to its simplicity and its short turnaround time.

[Haemophilus influenzae type b invasive disease in Catalonia (1996)]. / Enfermedad invasiva por Haemophilus influenzae tipo b en Cataluña (1996).

BACKGROUND: The purpose of this study was to find out the incidence and characteristics of H. influenzae type b invasive disease (HibID) in Catalonia, Spain. MATERIAL AND METHODS: An active surveillance of H. influenzae isolated from normally sterile sites was carried out during 1996. Microbiology laboratories of hospitals of Catalonia were periodically contacted by telephone. The serotype of all the strains was studied. RESULTS: The incidence of H. influenzae invasive disease (HIID) was 7.1 per 100,000 in children under 5 years and 1.0 per 100,000 in those over 5 years. The incidence of serotype b was 6.4 per 100,000 children under 5 years and 0.2 above this age. Only three strains belonged to types other than b (d, e and f). CONCLUSIONS: The incidence of HIbID is uncommon in Catalonia, lower than that registered in the prevaccine era in other countries and regions of the same geographical area.

[Neonatal sepsis by Malassezia furfur.]. / Sepsis neonatal por Malassezia furfur.

We report one case of neonatal sepsis caused by Malassezia furfur in an infant who had been in the Intensive Care Unit for 64 days. She had received prolonged therapy with intravenous fat emulsion. We used Sabouraud's medium with an overlay of sterile olive oil for the blood culture, because we had observed yeast forms in one smear of peripheral blood. M. furfur was isolated after three days of incubation. The patient recovered following removal of the port-a-cath and antifungal treatment, and had no further evidence of fungal infection. The skin colonization by the same yeast was demonstrated.

[Neonatal infection by Streptococcus agalactiae. Multicenter study in the area of Barcelona, Spain]. / Infección neonatal por Streptococcus agalactiae. Estudio multicéntrico en el área de Barcelona.

BACKGROUND: Streptococcus agalactiae or streptococcus group B (SGB) is the main etiologic agent of early neonatal sepsis. A multicenter study was performed with the aim of determining the incidence and characteristics of this disease in our medium and contribute the design of an adequate prevention protocol. METHODS: Ten hospitals and two primary health care centers were implicated in the study; 103 microbiology confirmed episodes of SGB neonatal sepsis (blood and/or LCR positive) were reported from 1994 to 1996. RESULTS: The incidence of early SGB neonatal sepsis was 1.48/1,000 live births with a mortality of 8.7%. The cultures, for detecting the state of the SGB carrier were performed in only 26 (25%) of the patients. At least one of the factors described for risk of perinatal SGB infection was observed in 46% of the mothers, with the most frequent being prolonged amniorrhea (26%), intrapartum fever (17%), and early delivery (14%). At the time of delivery only 10.7% of the mothers received endovenous antibiotherapy. CONCLUSIONS: From these results the following recommendations have been made: a) detection of SGB carriers by the systematic practice of blood cultures in the last weeks of gestation and b) the administration of intrapartum antibiotic prophylaxis in both early births (< 37 weeks) and in all the SGB carriers should be undertaken. With these measures we aim to decrease the neonatal infections by streptococcus group B.

[Antibiotic sensitivity of Streptococcus pyogenes in pediatrics]. / Sensibilidad antibiótica de Streptococcus pyogenes en pediatría.

BACKGROUND: The purpose of this study was to set up the current level of Streptococcus pyogenes sensitivity, in pediatric patients in our community, to penicillin, clindamycin, clarithromycin, erythromycin and azithromycin. MATERIAL AND METHODS: 100 strains were collected between October 1996 to July 1997. 79 were pharyngeal and 21 were non-pharyngeal strains. The MICs were obtained by the E-test method, and furthermore the results were compared by the Kirby-Bauer method. RESULTS: All strains were sensitive to penicillin and except one (inducible resistance) to clindamycin. 19% were resistant to macrolide, without differences among clarithromycin, erythromycin and azithromycin. From 13 strains (16.5%) of pharyngeal and 6 (28.5%) from non-pharyngeal samples, 4 of these from cutaneous samples, showed resistance. 18 of the resistance strains belonged to novel resistance fenotip and one to 10 inducible fenotip. Only minor discrepancies about erythromycin and clindamycin were observed between E-test and Kirby-Bauer methods. CONCLUSIONS: This study confirms a remarkable level of resistance to macrolides in pediatric patients, mainly in the cutaneous samples. Due to the reduced prevalence of macrolide-susceptible strains, in vitro susceptibility testing appears necessary in case of macrolide chemotherapy.

[Recurrent infection by Streptococcus agalactiae]. / Infección recidivante por Streptococcus agalactiae.

BACKGROUND: To study the factors implicated in the infectious process (host, microorganism and antibiotic) of a newborn early sepsis by S. agalactiae that suffered a reactivation at day five from discharge. METHODS: Description of two episodes of newborn sepsis by S. agalactiae corresponding to the same patient and microbiologic study of the isolated strain: typing by "genomic macrorestriction" and antibiotic tolerance by "timed killing curves". RESULTS: It was demonstrated that both strains of S. agalactiae type la/c belonged to the same clone as well as the tolerance to ampicillin of the strain. DISCUSSION: This sort of infections processes in the newborn are very serious and there is possibility of relapse. Thus, it is important to study the ethiologic agent and its relationship with antibiotics, in order to stablish the best treatment regimes, avoiding the possibility of relapses as the case we have described.

[Study of the viral etiology of lower respiratory tract infections in a neonatal unit]. / Estudio de la etiología viral de las infecciones del tracto respiratorio inferior en una unidad de lactantes.

OBJECTIVE: To study the possible viral etiology in 139 infants with lower respiratory tract infection who required hospitalization in the Infant Unit of our hospital, from October 1994 to June 1995. PATIENTS AND METHODS: 139 patients were admitted, aged from 13 days to 14 months, during this period. The etiological agent was detected by direct immunofluorescence from nasopharyngeal secretions. Monoclonal antibodies were used against Respiratory Syncitial Virus, Influenza A Virus, Influenza B Virus, Adenovirus and Parainfluenza 3 Virus. Antibody detection against these viruses by Complement Fixation Test was done on 29 of these patients, with paired sera (acute and convalescent phase). RESULTS: In 82 patients (59%) we found at least one viral agents from the nasopharyngeal specimens, but in 64 of these only one was detected, in the remaining 18, there were more than one. Significant levels of antibodies were detected in only six of the 29 patients tested. Serology was negative in the remaining 23 patients. CONCLUSIONS: Syncitial Respiratory Virus is the first virus responsible for the lower respiratory tract infection in this age group (49%). There was no correlation between serological diagnosis and antigen detection.

Urine sample used for congenital toxoplasmosis diagnosis by PCR.

The diagnosis of toxoplasmosis in congenitally infected infants can be difficult; serology is unreliable, and diagnosis must be based on the combination of symptomatology and direct demonstration of the parasite. Four infants suspected of having Toxoplasma gondii infection were studied by serological analysis, tissue culture, and PCR determination. T. gondii was isolated from the urine of one patient. The parasite was detected by PCR in the blood and cerebrospinal fluid of three infants and in the urine in all patients. Because nested PCR proved to be a sensitive, relatively rapid, and specific method and because it can be applied to a variety of different clinical samples, PCR can be a valuable technique for the identification of T. gondii infections in children. The present study indicates that PCR examination of urine, a fluid never before used for diagnosis in this age group, may be valuable in diagnosing cases of congenital toxoplasmosis.

[Microbiological study of the respiratory tract in children with cystic fibrosis]. / Estudio microbiológico del tracto respiratorio en niños afectados de fibrosis quística.

PURPOSE: Pulmonary infections is a main cause of morbimortality in patients suffering from cystic fibrosis. The objective of this study was to know the flora implicated in respiratory pathology of all mucoviscidotic children attending Hospital Sant Joan de Déu of Barcelona. METHODS: Quantitative cultures from respiratory samples (most of them: sputum) of 26 patients were performed from January 91 to June 93. There were 13 girls and 13 boys, aged 1 to 13 years (mean: 7 years). RESULTS: 282 microorganisms were isolated from 203 positive samples. Cultures of 88.4% of patients yielded in some moment Haemophilus influenzae, 82.6% of them Haemophilus parainfluenzae, 65.3% Pseudomonas aeruginosa, 50% Streptococcus pneumoniae, 38.4% Staphylococcus aureus. The most prevalent microorganism was P. aeruginosa (66%) followed by H. influenzae (29%) and S. aureus (26.6%). 59% of P. aeruginosa strains showed a mucoid phenotype. CONCLUSIONS: Haemophilus sp. causes short term infections that affect children of all ages, whereas infections due to P. aeruginosa persist in spite of correct antimicrobial therapy.

[Evaluation of the E test method in the antimicrobial sensitivity of Neisseria meningitidis to penicillin]. / Valoración del método E test en el estudio de la sensibilidad antimicrobiana de Neisseria meningitidis frente a penicilina.

BACKGROUND: The E test (AB Biodisk, Solna, Sweden) is a rather new method for performing antimicrobial susceptibility test--their results are generated directly as MICs. Due to its simplicity, is available in nearly all laboratories. The present study evaluates the effectiveness of the E test for susceptibility studies of Neisseria meningitidis to penicilline. METHODS: The MICs of penicilline of 55 strains of Neisseria meningitidis, studied by E test and by microdilution method, were compared to those obtained by agar dilution using both Mueller-Hinton (MH) and Mueller-Hinton with a 5% of sheep blood (MH+S) as test culture bases. RESULTS: The concordance rate (+/- 1 log2 of dilutions) was 100% in all cases, except for the E test on MH+S which yielded a 98.2% value. The Pearson's correlation coefficients were 0.95 and 0.84 for the E test and 0.88 and 0.85 for microdilution, using MH and MH+S. Roughly 70% of strains were considered susceptible to penicillin using MH for the in vitro tests, whereas only 40% of them were so considered using MH+S. CONCLUSIONS: The E test can be considered a good alternative to agar dilution method when testing susceptibility of N. meningitidis to penicilline, and MH is the best culture base for these assays.