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Introduction: The introduction of pneumococcal conjugate vaccine (PCV-7) has modified the epidemiology of invasive pneumococcal disease (IPD). Our aim was to investigate the epidemiological features of IPD before and after implementing the use of PCV-7., Methods: All invasive Streptococcus pneumoniae strains isolated in our hospital from 2000 to 2006 were included. Serotypes were identified and antibiograms were performed in all cases. Data obtained before (2000-2001) and after (2004-2006) authorization of PCV-7 use in Spain were compared., Results: There were 241 cases of IPD. None of the patients with IPD aged 2 years or younger had received PCV-7. PCV-7 coverage in children aged 5 or younger was about 48%. There was a non-significant increase in the incidence of IPD in children (from 53.8 to 57.8 cases/100 000 population), with no change in adults. When IPD incidence was adjusted by the number of blood samples collected, there was a non-significant decrease in both children and adults. Since PCV-7 came on the market, there has been a decrease in vaccine serotypes and an increase in non-vaccine serotypes. The emergent serotypes since that time include 3, 6A, 15, and 19A. Penicillin resistance decreased significantly (p<0.001) from the pre-vaccine period (87.3%) to 2003 (13.8%), and later rose from 2003 through 2006 (41.7%). Erythromycin resistance showed no changes during the study., Conclusions: The incidence of IPD in children aged 2 years and younger in Gran Canaria has not decreased despite the introduction of PCV-7. However, there has been a reduction in the number of cases related to vaccine serotypes and a significant decrease in penicillin resistance. In contrast, non-vaccine serotype IPD cases have increased. Universal vaccination and the use of new polyvalent vaccines may enhance these effects.

Objective: To assess the performance of a polymerase chain reaction (PCR) method in cerebrospinal fluid (CSF) for the diagnosis of nervous system infections caused by herpesvirus, and to estimate the incidence of encephalitis due to herpes simplex virus type 1 in the adult population of the island of Gran Canaria., Methods: We studied 330 CSF specimens from 312 patients (281 HIV-negative and 31 HIV-positive) remitted to investigate clinically suspected encephalitis or meningitis, or to study neuropathy or demyelinating disease. A multiplex PCR technique was used to detect herpes simplex virus types 1 and 2 (HSV-1 and HSV-2), varicella-zoster virus (VZV), human cytomegalovirus (CMV), Epstein-Barr virus and human herpesvirus type 6. The patients' clinical records were reviewed to establish the definite diagnosis., Results: Nine samples from eight patients (2.6%) showed positive results (9.7% of patients with pathological CSF and none with normal CSF). The eight patients had clinical and analytic findings of herpesvirus nervous system infection: HSV-1 DNA in four patients with encephalitis, HSV-2 DNA in one patient with meningitis, VZV DNA in two patients with meningitis and CMV DNA in one HIV-positive patient with encephalitis. Herpesvirus was the cause of 50% of encephalitis cases and 10% of meningitis cases. The incidence of HSV-1 encephalitis was five cases per million inhabitants per year., Conclusions: Diagnosis of herpesvirus nervous system infections by PCR in CSF is not appropriate when CSF parameters are normal. We found a higher incidence of herpesvirus encephalitis than has been reported in other studies.

Introduction: Since the implementation of routine vaccination against mumps, enteroviruses have become the commonest cause of viral meningitis. In Spain the most frequently isolated echoviruses are serotypes 30, 9, 6 and 4.Objectives. Determine the clinical-epidemiological characteristics of a meningitis outbreak due to echovirus type 13., Methods: We studied 152 cases of enteroviral meningitis diagnosed in the year 2000. Viral isolation was performed on fibroblast MRC-5 and human rhabdomyosarcoma cells. The viruses were identified with monoclonal antibodies and serotyped by neutralization., Results: Echovirus was isolated in 131 out of 152 CSF samples (86.2%). In 21 patients with negative CSF culture, the diagnosis was made by echovirus isolation from upper respiratory tract and/or feces samples. The cytopathic effect was seen in all cases in monolayers of rhabdomyosarcoma cells. The average age of the patients was 67 months (range: 1-350) and the male:female ratio was 2:1. Most of the patients had fever, headache and other signs of meningitis. Hospitalization was required in 52.6%. All patients were discharged without sequelae. The highest incidence was recorded from April to June., Conclusions: There had been no record of the presence of echovirus 13 in Spain in recent years until the emergence of this outbreak. Isolation of the virus from sites other than CSF is often helpful in establishing the diagnosis and patient management. Enterovirus isolates must be specifically serotyped to determine enteroviral activity in the population, which can be sporadic or epidemic.

Objective: To evaluate the performance of the Amplified Mycobacterium tuberculosis Direct Test 2- Gen Probe (AMTD- 2) for direct detection of Mycobacterium tuberculosis in smear-negative samples., Patients and Methods: From January to December 1999, 683 specimens, 333 respiratory and 350 non-respiratory ones collected from 457 patients, were included in the study. All the samples of HIV-positive patients, the respiratory samples from patients suspected of having pulmonary tuberculosis (at least two by patient) and all non-respiratory samples were included. As diagnosis method of reference, the culture isolation was considered. Clinical data were analyzed in case of discrepant results and clinical diagnosis was considered the reference criteria. The technique was performed once a week., Results: The sensitivity, specificity, and positive and negative predictive values of this assay were 58.9%, 93.9%, 37.1% and 97.4% respectively related to the standard culture. When referred to clinical diagnosis of active tuberculosis, these values improved to 70.4%, 97.7%, 73.1% and 96.8% respectively (in respiratory samples were 67.6%, 98.6%, 86.2% and 95.9% and in nonrespiratory ones 76.5%, 96.9%, 56.5% and 98.7% respectively). The mean time of diagnosis by culture and by AMTD-2 were 20.3 days (range 10-63) and 5.7 days (range 2-20) respectively., Discussion: It is concluded that AMTD-2 is a rapid diagnosis method when clinical data are sugestive with active tuberculosis. However, due to the low positive predictive value, it would be convenient to obtain successive samples to confirm the result in patients without clinical evidence of tuberculosis.

Objective: To analyze the prevalence of infection, the frequency of HCV genotypes and the epidemiology characteristics among the patients in hemodialysis treatment in one 25 years old hospital hemodialysis center and one 15 years old secondary unit by a transversal cross-section study in 1998., Patients and Methods: 171 hemodialyzed-patients were studied. Patients sera were analyzed by the presence of HCV antibodies anti-VHC by a enzymoimmunoassay (Abbott Cientifica) and the presence of antibodies was confirmed by a line immunoassay (Inno-LIA HCV AbIII) and by the presence of VHC-RNA by reverse transcriptase PCR (Cobas Amplicor HCV). Genotypes were determinate by reverse hybridization (Inno-LIA HCV III)., Results: Fifty (29.2%) of the patients were HCV antibody positive. Forty-five (26.3%) were HCV-RNA positive, all of them with antibodies positive. The distribution of genotypes was: 1b, 34 (75.5%); 4f, 4 (8.9%); 1a, 3 (6.7%); 1, 3 (6.7%) and 1 case could not be typed (2.2%). In 14 patients (28.0%), seroconversions were documented Twenty-one patients (42.0%) were diagnosed when the routine tests were available and 15 patients (30.0%) were diagnosed pre-dialysis. The multivariate analysis showed that the risk of HCV infection was greater for patients who had been more 8 years on dialysis (OR: 6.22; 95% CI: 1.24-31.07)., Conclusions: Data presented indicate that the prevalence of HCV infections in our hemodialysis units and the number of seroconversions were high and the HCV subtype 1b was more frequent; because of this, the screening by both serological and molecular methods is necessary, at least twice a year, to identify all the infected patients. Besides, we think that is necessary to increase the control of the completion of the Universal Precautions.

Objective: To evaluate the polymerase chain reaction in the diagnosis of pulmonary tuberculosis in children., Patients and Methods: 135 samples (68 sputum and 67 gastric aspirates) of 72 patients under 15 years old with suspected tuberculosis and a negative acid-fast stain were included in the study. In all the samples an acid-fast stain and culture in Lowestein-Jensen with and without piruvate were performed. Also, a specific detection of Mycobacterium tuberculosis complex (MT) was made by PCR (Amplicor-MT-Roche Diagnostic). Tuberculosis was certainly diagnosed when M. tuberculosis was isolated or clinical evidence of tuberculosis in positive-PCR cases with negative culture was achieved., Results: Ten samples of six patients were positive culture. Four of these samples were positive PCR. In addition, two samples of two patients with negative culture were positive PCR. Both patients had a clinical diagnosis of pulmonary tuberculosis with effective anti-tuberculosis treatment, one of them had also another positive PCR and culture sample. The results of sensitivity, specificity, positive predictive value and negative predictive value by patient according to the reference methodology were 57.1, 100, 100 and 95.4%, respectively, and by sample 66.6%, 100, 100 and 96.8%, respectively. Other 15 patients presented pulmonary tuberculosis with negative PCR and culture; so the sensitivity of the culture and the PCR regarding a clinical diagnosis were 27.3% (6/22) and 18% (4/22) respectively., Conclusion: Due to the diagnosis by culture takes a long time and the low percentage of samples of pediatric patients with positive acid-fast rain stain, the PCR would be useful in order to achieve quickly and specific diagnosis of tuberculosis in a high-prevalence population.

Background: To compare the diagnosis utility of a reverse transcription-polymerase chain reaction (RT-PCR) for detection of enteroviral RNA in cerebrospinal fluid (CSF) in comparison to viral culture for central nervous system infections in pediatric population and to know the clinic epidemiological characteristics of this infection., Methods: From June to December of 1997, 116 CSF samples of children were included in the study. The samples were inoculated in MRC-5 and HEP-2 and the enterovirus RNA was detected with AMPLICOR-Enterovirus (Roche Diagnostic System). The virus were typed by neutralization., Results: 36 samples were positive (30 were positive for RT-PCR and 6 for RT-PCR and viral culture). The media time in detect the CPE was 4.8 days. The viruses found were four echovirus 6, one echovirus 30 and one echovirus 7. Fifteen children were under 6 months (93.3% under two months) and 21 children over 6 months with a media age of 81 months (range, 38-160 months). In over 6 months old children, the most frequent clinical presentation was meningitis aseptic syndrome with pleocytosis and in under 6 months old ones was fever and only 60% of these children had pleocytosis. The evolution was good in all the cases., Conclusions: AMPLICOR-Enterovirus is a sensitive method for the diagnosis of enteroviral meningitis. The clinical manifestations are different with the age and due to the absence of neurological symptoms and pleocytosis in the patients under two months, we think that it is necessary to study the presence of enterovirus with genetic amplification methods in this population of patients.

Objective: To analyse the prevalence of HCV genotypes among patients from Gran Canaria and the relation with the routes of viral transmission, date of primoinfection and severity of hepatic lesion., Patients and Methods: 179 patients were studied. In 61 patients the date of exposure was determinate. Liver biopsies were obtained in 139 patients. Genotypes were determinate by reverse hybridisation using InnoLiPA genotyping kit (Innogenetics)., Results: The distribution of genotypes was: 1b, 114 (63.7%), 1a, 30 (16.7%); 1, 17 (9.5%); 3a, 7 (3.9%); 4c/4d, 6 (3.3%); 2, 1 (0.5%); 2a/2c, 2 (1.1%), 3, 1 (0.5%) and 4f, 1 (0.5%). We did not find any case of coinfection with a second genotype. In univariable analysis, we found statistically differences in sex (78.9% of women infected with genotype 1b compared with 55.1% of men, p < 0.01 and 31.6% of men infected with 1a, 3a and 4c/4d compared with 15.7% of women, p < 0.01) and age (median age in genotype 1b 45 +/- 12 years vs 36 +/- 9 years in the other genotypes, p < 0.01). HCV subtypes 1a and 3a were predominant in patients IVDA (47.6% and 23.85% respectively) and 1b in blood transfusion receptors (71.2%) (p < 0.01). In 40.2% of the patients, the sources of infection were unknown. In the multivariable logistical regression analysis we found the only factor influencing the genotypes distribution was the transmission mechanism (p < 0.001) and sex and age are relationated with the transmission mode. The media infection duration in patients infected with 1b was 22 +/- 11 years vs 9 +/- 6 years in the other genotypes. We found differences in the liver histologic findings and the age of the patient, but not in the different genotypes., Conclusions: Our study reflects the higher frequency of HCV subtype 1b in our area and a different prevalence of genotypes in relation to mode of transmission. Our results suggest that in our media the liver damage seems to be directly influenced by the age of the patient, but not influenced by HCV genotype.

Background: It is necessary to have an easy and quickly test to distinguish "false positive" rubella IgM results and residual antibodies from the antibodies produced in the primary infection, in pregnant women. The avidity of IgG antibodies test seems to differentiate between primary rubella infection and past infections, reinfections or postvaccination, showing its utility in the diagnosis of primary infection in other infectious diseases., Method: For 30 months, 178 sera from 157 patients with clinical and/or epidemiological rubella suspicion or with a positive rubella IgM result as result of an accidental serological finding, were remitted to our laboratory for a serological follow up. We distinguished 3 patient groups: outbreak group, 112; pregnant women, 36, and newborn 11. Rubella IgM antibodies by indirect EIA previous the rheumatoid factor absorption; IgG antibodies of low avidity by indirect EIA previous treatment of serum with 6 M urea, were detected in the sera. It considered a positive result, a rubella avidity index (AI) < 50%., Results: In the epidemic outbreak group, 90.2% of the patients were not vaccinated. 80% of cases occurred in young men between 14 an 20 years old. From 109 patients (97.3%) with rubella IgG antibodies, 92 (84.4%) showed AI-IgG lower than 50%. In this group, the mean rate of AI-IgG rubella was 29.0%. In the pregnant women group, except for two of them, rubella IgM antibodies were an accidental finding in a serological pregnancy screening. Thirty patients (83.8%) showed AI-IgG rubella > 50%. The two pregnant women who had evidence of clinical and epidemiological rubella showed AI-IgG rubella of 37.4% and 20.9%. Another four pregnant women showed AI-IgG rubella close to cut-off (44.7-49.0%). The mean AI-IgG rubella in this group was 71.8%. The mean AI-IgG Rubella between the epidemic outbreak group and the pregnant women group, 29.0 and 71.8% respectively, was statistical significance (p < 0.001)., Conclusions: The avidity IgG test is simple and quickly, and it allow to exclude most of positive results because of residual IgM antibodies and false reactive.

Background: Schistosomiasis in Spain is always an imported disease mainly presented in travellers from endemic areas with a history of having bathed in fresh water and in immigrants from these areas. A group of travellers presenting infection by schistosomes following an 8-day journey to Burkina Faso., Patients and Methods: The travellers, residents of Gran Canaria (Spain), who had bathed in fresh water were studied by schistosomiasis serology and parasitologic examination in stools and urine., Results: A total of 29 travellers were studied, 20 (69%) of whom were considered to be infected, on presenting positive serology and/or coproparasitologic examination. Fourteen of the infected patients presented clinical symptomatology compatible with the Katayama syndrome, while 6 were asymptomatic. The mean time to appearance of the symptoms was 27 days and these were most frequently fever, headache, neck pain, diarrhea and arthromyalgia together with eosinophilia achieving a mean value of 3,513 eosinophils/microliter. All the infected travellers presented positive serology and in 5 eggs of a Schistosoma mansoni were observed in stools. All the infected patients were treated with praziquantel., Conclusions: Limited exposure by bathing in fresh water in this group of travellers led to a high rate of infection. The diagnosis of schistosomiasis should be considered in any traveller from an endemic area with a history of having bathed in fresh water. In the case of an outbreak, investigation of all the travellers who had bathed is recommendable given that the infection may be asymptomatic.

Background: The eastern region of Canary Islands presents certain climatic and atmospheric conditions which differentiate it from the accepted parameters in cases of Lyme disease. We present a serologic study of patients with clinical syndrome which is potentially compatible with Lyme disease, in an effort to clarify the presence of this disorder region., Material and Methods: We assayed type IgG and IgM antibodies against the flagellin antigen of the native Borrelia burgdorferii using indirect enzymeimmunoassay (EIA) as a screening technique. In the serum presenting positive screening we confirmed this result with immunoblot (IB) type IgG and/or IgM with synthetic peptides for the antigenic epitopes p14, p41, p100, OspA and OspC. We review the clinical history of the patients with reactive sera., Results: We studied a sample group of 1,452 patients considered clinically compatible with Lyme disease over a 42-months period, presenting the screening results for serologic positive 47 (3.2%). From this sample, 24 (1.65%) were IB reactive, independent of the type of immunoglobulin. Only two fulfilled the criteria of both IB-IgM positive, one with antibodies against OspC and p41 proteins finally diagnosed as arteriosclerotic encephalopathy suboccipital Binswanger and another with antibodies against p100 and p41 proteins, diagnosed as presenting a primary cytomegalovirus disease. The bands that, most often lead to reactive IB were p41 and p14. Of the 24 patients who presented reactive IB, 14 (58.3%) also presented other previous data wich produced the false positives, 8 with autoimmune disease, 5 viral infectious and one infection due to Treponema pallidum., Conclusion: Due to the lack of studies carried out in this field which would verify or rule out an epidemiologic chain in our region, our serologic and clinical data put the eastern Canary Islands in doubt as an endemic area of Lyme disease.

Background: IgG antibodies produced early in infection has a low avidity to their respective epitopes, so that an assay to detect those antibodies could be easily used to diagnose a recent primary infection. A prospective study of anti-CMV IgG avidity test in patients with microbiological evidence of active CMV infection was made., Methods: One hundred thirty-five patients were studied. All patients sera were tested for CMV antibodies "pool" IgG/IgM, IgM and antibody IgG avidity index (AI). Furthermore, samples of blood leucocytes from immunosuppressed patients to detect CMV viremia by conventional and shell-vial cell culture isolation and to detect CMV antigenemia, were processed. The avidity index IgG-CMV (AI IgG-CMV) less than 60% was defined as a positive result. CMV infection and disease were defined., Results: The avidity index was < 60% in 16.3% of all patients and in 68.7% of patients with CMV disease. AI IgG-CMV was positive in 81.8% of patients with primary CMV disease and 9.1% with secondary CMV disease. The mean avidity index reading was 35% in primary CMV disease, 88.3% in secondary CMV disease (p < 0.001) and 87.9% in infected patients without CMV disease criterion (p < 0.001). The sensitivity, specificity, VPP and VPN of avidity index IgG-CMV were 85.7%, 97.4%, 75.0% and 94.9% respectively, in primary CMV disease diagnostic respect to all patients with microbiological evidence of active CMV infection., Conclusions: Avidity index IgG-CMV seems to be a good serological test to diagnose primary CMV disease with only one serum, probably with independence of patients immune state.

Background and Methods: Human infections caused by Listeria monocytogenes often present as sporadic cases without any epidemiological relationship among them; however they also appear as outbreaks that are usually detected by an increase in the number of cases diagnosed by hospitals of the geographic area. Between December 1991 and May 1993, twenty four cases of listeriosis were detected in three hospitals of Las Palmas de Gran Canaria; and they were classified as an outbreak. Our report describes its clinical, epidemiological and microbiological aspects., Results and Conclusions: Twenty four cases of listeriosis were diagnosed, 12 occurred in pregnant women or neonates (5 and 7 respectively) and 12 in non pregnant adults. All adult infections were community-acquired. The incidence rate was, for the epidemic area, 76.3 cases per million population during the period considered (18 months). Among non pregnant adults, 9/12 patients had some underlying disease and 9/12 presented CNS affection (meningitis and/or cerebritis). In the group of pregnant women, 4 cases occurred in the second trimester and fetal loss was caused; one case was detected in the third trimester and four weeks later the patient delivered an unaffected infant. All cases of neonatal listeriosis presented as early-onset sepsis. Of the 24 strains of L. monocytogenes, 21 were serotype 4, two were serotype 1 and one was not typeable. Strains from 12 patients were available for epidemiological analysis, seven of which corresponded to the same pattern and there were three more different patterns.

Background: A prospective microbiological study of the vaginal swab specimens from premenarcheal girls with clinical diagnosis of vulvovaginitis was done from the 1st of September 1991 to the 31st of August 1994., Patients and Methods: Vaginal secretions from premenarcheal girls with clinical findings were examined. Most important pathogenic agents were investigated and if there was an inflammatory reaction in the Gram stain and a heavy growth on culture, other potentially pathogenic agents were considered also., Results: In 70 (28.7%) of the 262 patients a potentially pathogenic microorganism was found: eight cases (3.0%) due to Streptococcus pyogenes, four cases (1.5%) due to Candida albicans. Only in one case Neisseria gonorrhoeae was isolated. Among the uncertain etiologic agents, Haemophilus influenzae was the most frequently isolated (7.6%). In 25 (12.6%) of the 198 patients Enterobius vermicularis ova were visualized., Conclusions: Streptococcus pyogenes was the most frequently related organism with the vulvovaginitis syndrome among the traditionally established pathogens. The role of Haemophilus influenzae should be considered due to the high prevalence of isolation in this group of patients. We consider that differential diagnosis with Enterobius vermicularis infestation should be done in all cases.

Background: IgM serologic response in the diagnosis of acute toxoplasmosis presents interpretation problems. A comparative study with IgA detection of antibodies was performed., Methods: A parallel serologic study was carried out with IgM and IgA enzymoimmunoassay enhancement techniques in the sera of patients suspected of having toxoplasmosis., Results: Positive results for IgM and/or IgA were presented in 74 sera (47 patients): 86.3% for the former and 58.9% for the latter (p < 0.001). The group of IgA-/IgA+ sera presented a low mean of proportionality index (PI): 1.6 versus the IgM+ sera group in the context of IgG seroconversion with a PI of 3.4 (p < 0.001). Out of the 9 patients with demonstrated IgG, all were IgA+ and seven IgM+., Conclusions: The present data seem to support greater specificity of the determination of IgA antibodies than that of IgM in the diagnosis of acute toxoplasmosis.

The 40/41 adenovirus plays an important role as the productive agent of gastroenteritis at a pediatric age according to recent studies. With the aim of evaluating the clinical-epidemiological importance of this agent in our medium a prospective study of the 40/41 adenovirus was carried out in 1,697 stools of children of under 14 years of age over a period of 2 years. An enzyme immunoassay technique with specific monoclonal antibodies was used for detection. The 40/41 adenovirus was the third cause of gastroenteritis following Salmonella sp. and rotavirus with a percentage of infection of 2.1%. In 87.1% of the patients in which it was detected the patients had an age of less than 24 months. A clear peak of infection was found in the months of September of the two years studied. The infection was of intrahospital origin in 46.2% of the patients. Most of the children presented a self-limited diarrheic picture. The evolution of the patients was good with adequate rehydration measures. The study of the 40/41 adenovirus is of indubitable interest with the aim of obtaining greater knowledge of its importance in the epidemiology and clinical manifestations of gastroenteritis.

Verotoxin-producing Escherichia coli strains have been associated with acute hemorrhagic colitis since 1982. We have systematically investigated this pathogen in our laboratory, in all stool samples submitted for culture during a fourteen month period, by using MacConkey sorbitol agar to isolate non sorbitol fermenting Escherichia coli strains. Coated latex particles with an antiserum against Escherichia coli O157 were used to detect O157 serogroup Escherichia coli. A completed serological study and verotoxin assay was performed in all positive strains. We have found two non-related cases of verotoxigenic Escherichia coli infection in two children. In one case, the main clinical picture was an acute hemorrhagic colitis and the other one was a diarrhea without presence of blood, with fever and vomiting. Both cases improved without antimicrobial treatment. No systemic complications appeared in any of the cases during the infection. The infection incidence was 0.07% of all positive stool cultures. The few documented cases of this infection in our country should encourage to investigate this pathogen in order to know its real incidence in our environment.