A multivariable prediction model for intra-amniotic infection in patients with preterm labor and intact membranes including a point of care system that measures amniotic fluid MMP-8.

OBJECTIVES: Among patients with preterm labor and intact membranes (PTL), those with intra-amniotic infection (IAI) present the highest risk of adverse perinatal outcomes. Current identification of IAI, based on microbiological cultures and/or polymerase chain reaction amplification of the 16S ribosomal RNA gene, delay diagnosis and, consequently, antenatal management. The aim to of the study was to assess the performance of a multivariable prediction model for diagnosing IAI in patients with PTL below 34.0 weeks using clinical, sonographic and biochemical biomarkers. METHODS: From 2019 to 2022, we prospectively included pregnant patients admitted below 34.0 weeks with diagnosis of PTL and had undergone amniocentesis to rule in/out IAI. The main outcome was IAI, defined by a positive culture and/or 16S ribosomal RNA gene in amniotic fluid. Based on the date of admission, the sample (n=98) was divided into a derivation (2019-2020, n=49) and validation cohort (2021-2022, n=49). Logistic regression models were developed for the outcomes evaluated. As predictive variables we explored ultrasound cervical length measurement at admission, maternal C-reactive protein, gestational age, and amniotic fluid glucose and matrix metalloproteinase-8 (MMP-8) levels. The model was developed in the derivation cohort and applied to the validation cohort and diagnostic performance was evaluated. Clinical management was blinded to the model results. RESULTS: During the study period, we included 98 patients admitted with a diagnosis of PTL. Of these, 10 % had IAI. The final model included MMP-8 and amniotic fluid glucose levels and showed an area under the receiver operating characteristic curve to predict the risk of IAI of 0.961 (95 % confidence interval: 0.860-0.995) with a sensitivity of 75 %, specificity of 93.3 %, positive likelihood ratio (LR) of 11.3 and negative LR of 0.27 in the validation cohort. CONCLUSIONS: In patients with PTL, a multivariable prediction model including amniotic fluid MMP-8 and glucose levels might help in the clinical management of patients undergoing amniocentesis to rule in/out IAI, providing results within a few minutes.

Differences in Drug-Susceptibility Patterns between Mycobacterium avium, Mycobacterium intracellulare, and Mycobacterium chimaera Clinical Isolates: Prospective 8.5-Year Analysis by Three Laboratories.

Background: It has been suggested that Mycobacterium avium, Mycobacterium intracellulare, and M. chimaera have differential drug susceptibility patterns. We prospectively analyzed and compared the drug susceptibility patterns among these species over an 8.5-year period. Methods: A microdilution method (Slomyco®) was performed for drug susceptibility testing of 402 M. avium, 273 M. intracellulare, and 139 M. chimaera clinical isolates. Results: M. avium showed significantly higher resistance to moxifloxacin, ciprofloxacin, rifampicin, ethambutol, streptomycin, linezolid, cotrimoxazole, and clarithromycin. M. avium also showed higher minimum inhibitory concentrations (MIC) than M. intracellulare and M. chimaera against all drugs except ethionamide, to which M. intracellulare and M. chimaera showed greater resistance. Conclusions: Our series demonstrated differential drug resistance patterns among the most frequent M. avium complex species. M. avium was more resistant than M. intracellulare and M. chimaera versus eight antibiotics and showed greater MIC values to most of the antibiotics studied. These data suggest that knowledge of the local distribution and susceptibility profiles of these pathogens is essential for adequate clinical management.

Rapid molecular syndromic testing for aetiological diagnosis of gastrointestinal infections and targeted antimicrobial prescription: experience from a reference paediatric hospital in Spain.

Aetiological diagnosis of gastrointestinal infections is challenging since a wide range of bacteria, parasites and viruses can be causal agents and derived clinical manifestations appear quite similar. Our aim was to evaluate contribution of the novel QIAstat-DxGastrointestinal Panel (GIP) to aetiological diagnosis of gastrointestinal infections and rational antimicrobial prescription in a reference paediatric hospital. Evaluation included comparison of diagnostic yield and agreement of results of QIAstat-Dx GIP and conventional microbiological methods. Parallel testing was performed on stool samples collected prospectively from children admitted to Sant Joan de Deu Barcelona Hospital (Spain) during the period February-March 2019. Influence of the panel test use on antimicrobial prescription was assessed using a pre-post study design. Eighty-six (68.8%) out of 125 specimens were positive by QIAstat-Dx GIP versus 44 (35.2%) positive by a composite of conventional methods (p<0.001). Global agreement of panel test results with rotavirus-adenovirus antigen detection (92.8%) and a two-step antigen/toxin and PCR-based algorithm for toxigenic Clostridioides difficile detection (87.5%) was greater than that with bacterial culture (76.0%) and parasite microscopic identification (64.3%). Panel test results orientated antimicrobial prescription changes in 18 (14.4%) patients, including antimicrobial start in 11 cases initially untreated, targeted antimicrobial prescription in 5 and discontinuation in 2 cases empirically treated. Results showed that QIAstat-Dx GIP significantly expanded aetiological diagnosis of gastrointestinal infections compared to conventional microbiological methods while orientating a more judicious use of antimicrobial drugs in hospitalised children.

Performance Comparison of a Novel Rapid Stand-alone Molecular Test and a 2-Step Diagnostic Algorithm for Clostridioides difficile Detection in Children.

BACKGROUND: We aimed to evaluate diagnostic performance of the cobas® Liat® Cdiff test, a novel single-step automated polymerase chain reaction (PCR) assay for rapid diagnosis of toxigenic Clostridioides difficile infection (CDI) in stool samples from children with clinical symptoms of CDI. METHODS: Assessment of cobas Liat Cdiff diagnostic yield, time of analytical process and agreement of results with those of a 2-step diagnostic algorithm. The sequential algorithm combined an enzyme immunoassay (EIA) targeting antigen glutamate dehydrogenase (GDH), enterotoxin-A and cytotoxin-B, and a confirmatory PCR in EIA GDH-positive and toxin-negative samples. Fresh stool samples were collected prospectively from patients 2-18 years of age that were attended in Hospital Sant Joan de Deu (Barcelona, Spain) during December 2018-August 2019. RESULTS: A total of 122 specimens were collected from 91 children (mean age, 8 years; 69.7% male). cobas Liat Cdiff identified 24 (19.7%) positive samples. EIA yielded 97 (79.5%) GDH- and toxin-negative results, 11 (9.0%) GDH- and toxin-positive results, and 14 (11.5%) GDH-positive and toxin-negative results, of which 11 (9.0%) were positive for the toxin by the confirmatory PCR. Overall, GDH- and toxin-positive samples detected by the sequential algorithm were 22 (18.0%). Comparatively, the new test reduced time of the analytical process significantly (20 vs. 35.4 minutes, P < 0.001). CONCLUSION: Use of cobas Liat Cdiff showed similar detection yield compared with a 2-step diagnostic algorithm that combined an EIA and a confirmatory PCR while decreasing the time of the analytical process markedly in stool samples from children suspected of CDI.

Tuberculosis en el adolescente; reto y oportunidad de evitar el contagio a la comunidad / Adolescent tuberculosis; a challenge and opportunity to prevent community transmission

INTRODUCCIÓN: La tuberculosis (TB) en el adolescente puede presentar formas radiológicas cavitadas en los lóbulos superiores, con esputos bacilíferos, en lo que se ha llamado TB pulmonar tipo adulto, que implica un importante riesgo de contagio en el entorno social y familiar del paciente. PACIENTES Y MÉTODOS: Estudio observacional retrospectivo (2007-2012) en una serie pediátrica (< 18 años) con TB en un hospital pediátrico de referencia en Barcelona. Se compara a los pacientes ≤ 12 y > 12 años. RESULTADOS: Se incluyeron 124 pacientes (56,5% hombres, edad mediana: 4,0 años). En la mitad, la TB afectó a pacientes de origen inmigrante y se diagnosticó por sospecha clínico-radiológica. La TB intratorácica fue la forma clínica predominante (91,9%), los cultivos fueron positivos en un tercio de los casos (37,9%) y sensibles a los fármacos orales de primera línea en su totalidad. El tiempo mediano (rango intercuartil) de tratamiento fue de 6 (6-9) meses; solo 10 pacientes precisaron tratamiento directamente observado y la evolución fue satisfactoria en la mayoría (98,4%). Entre los adolescentes, la TB fue más prevalente en mujeres (63,2%) e inmigrantes (68,4%), la comorbilidad al diagnóstico y las formas pulmonares cavitadas fueron más comunes y se identificó el caso índice solo en el 21,1% de los pacientes. CONCLUSIÓN: En el adolescente, la TB pulmonar tipo adulto es común, y a menudo asocia comorbilidad y se diagnostica más tarde, implicando un mayor riesgo de contagio a la comunidad

INTRODUCTION: Adolescents may present with adult-type pulmonary tuberculosis (TB), including cavity disease in upper lobes and smear-positive sputum, which involves a significant transmission risk for social and family contacts. PATIENTS AND METHODS: A retrospective (2007-2012) observational study of a case series of TB was conducted in children and adolescents (< 18 years) in a paediatric referral centre in Barcelona. Patients aged ≤ 12 and > 12 years at diagnosis are compared. RESULTS: The series consisted of 124 patients (56.5% males, median age: 4.0 years). In half of the cases, the patient was of immigrant origina and TB was diagnosed after clinical-radiological suspicion, intra-thoracic disease being the most common (91.9%). Cultures yielded positive results in one third of cases (37.9%) and isolates were sensitive to oral first-line anti-TB agents in 100%. Median (interquartile range) duration of treatment was 6 (6-9) months, directly observed therapy was needed in 10 patients, and there was a satisfactory outcome after treatment in 98.4%. Among adolescents, TB was more prevalent in females (63.2%) and immigrant patients (68.4%), comorbidity at diagnosis and lung cavity forms were more common, and the source case was identified only in 21.1% of the patients. CONCLUSION: Adult-type pulmonary TB is common among adolescents, may be associated with underlying medical conditions, and is often diagnosed late, posing a significant transmission risk to the community

[Adolescent tuberculosis; a challenge and opportunity to prevent community transmission]. / Tuberculosis en el adolescente; reto y oportunidad de evitar el contagio a la comunidad.

INTRODUCTION: Adolescents may present with adult-type pulmonary tuberculosis (TB), including cavity disease in upper lobes and smear-positive sputum, which involves a significant transmission risk for social and family contacts. PATIENTS AND METHODS: A retrospective (2007-2012) observational study of a case series of TB was conducted in children and adolescents (<18 years) in a paediatric referral centre in Barcelona. Patients aged≤12 and>12 years at diagnosis are compared. RESULTS: The series consisted of 124 patients (56.5% males, median age: 4.0 years). In half of the cases, the patient was of immigrant origina and TB was diagnosed after clinical-radiological suspicion, intra-thoracic disease being the most common (91.9%). Cultures yielded positive results in one third of cases (37.9%) and isolates were sensitive to oral first-line anti-TB agents in 100%. Median (interquartile range) duration of treatment was 6 (6-9) months, directly observed therapy was needed in 10 patients, and there was a satisfactory outcome after treatment in 98.4%. Among adolescents, TB was more prevalent in females (63.2%) and immigrant patients (68.4%), comorbidity at diagnosis and lung cavity forms were more common, and the source case was identified only in 21.1% of the patients. CONCLUSION: Adult-type pulmonary TB is common among adolescents, may be associated with underlying medical conditions, and is often diagnosed late, posing a significant transmission risk to the community.

Blood Cultures Are Not Useful in the Evaluation of Children with Uncomplicated Superficial Skin and Soft Tissue Infections.

BACKGROUND: Blood cultures (BCs) are commonly performed on children admitted to hospital for skin and soft tissue infections (SSTIs). In recent years, this practice has been questioned in patients with uncomplicated SSTIs because of its low yield. At the same time, however, an increase in community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) infections has been described; its influence on rates of bacteremia in patients with SSTIs is unclear. The aims of the study were to describe the performance and the yield of BC in immunocompetent patients with uncomplicated SSTIs and to determine the prevalence of CA-MRSA as a causative agent in our area. METHODS: Retrospective study: immunocompetent patients younger than 18 years evaluated in the emergency department and admitted for uncomplicated SSTIs (cellulitis, abscess, impetigo or erysipelas) from July 1, 2010 to June 31, 2014 were included. Patients referred from other hospitals who were receiving parenteral antibiotics and patients with complicated SSTIs (surgical or traumatic wound infection, need for surgical intervention and infected ulcers or burns) were excluded. RESULTS: We included 445 cases: 348 (78.2%) cellulitis, 78 (17.5%) abscess and 19 (4.3%) impetigo. BCs were performed on 353 (79.3%) patients. Two (0.6%; 95% confidence interval: 0.2-2.0%) were positive and 10 (2.8%; 95% confidence interval: 1.5-5.1%) contaminated. The positive BCs grew S. aureus and Streptococcus pyogenes. Wound cultures were performed on 148 (33.3%) patients; 98 (66.2%) were positive. In 22 (22.4%) patients CA-MRSA grew, accounting for 14.9% of overall wound cultures. CONCLUSIONS: BCs are not useful in the management of immunocompetent patients admitted to the hospital with uncomplicated SSTIs. The prevalence of CA-MRSA is low in our area, but continuing careful surveillance is needed.

Occult bacteraemia is uncommon in febrile infants who appear well, and close clinical follow-up is more appropriate than blood tests.

AIM: The rate of paediatric occult bacteraemia after the introduction of the 13-valent pneumococcal conjugated vaccine is relatively unknown. We determined the rate, and identified isolated pathogens, in children aged three to 36 months who presented to a paediatric emergency department with fever, but otherwise appeared well. We also analysed the yield of laboratory parameters traditionally considered risk factors for occult bacteraemia. METHODS: Children aged three to 36 months who were febrile, but otherwise appeared well, were included if they had blood tests in the paediatric emergency department between April 2010 and September 2012. RESULTS: Of the 591 patients, only six (1.0%) had a true bacterial pathogen and three of those were Streptococcus pneumoniae (0.5%). None of the children with pneumococcal bacteraemia had been immunised. The contaminant rate was 2.7%, and an elevated band count was the best predictor of occult bacteraemia, with positive and negative likelihood ratios of 10 and 0.4, respectively. The yield of the other laboratory parameters was very limited. CONCLUSION: In the era of the 13-valent pneumococcal conjugated vaccine, occult bacteraemia is an uncommon event in febrile children aged three to 36 who otherwise appear well and close follow-up should replace blood analysis in such cases.

Differentiating Kingella kingae septic arthritis of the hip from transient synovitis in young children.

OBJECTIVE: To conduct a retrospective multicenter study to assess the ability of a predictive algorithm to differentiate between children with Kingella kingae infection of the hip and those with transient synovitis. STUDY DESIGN: Medical charts of 25 Israeli and 9 Spanish children aged 6-27 months with culture-proven K kingae arthritis of the hip were reviewed, and information on the 4 variables included in the commonly used Kocher prediction algorithm (body temperature, refusal to bear weight, leukocytosis, and erythrocyte sedimentation rate) was gathered. RESULTS: Patients with K kingae arthritis usually presented with mildly abnormal clinical picture and normal serum levels of or near-normal acute-phase reactants. Data on all 4 variables were available for 28 (82%) children, of whom 1 child had none, 6 children had 1, 13 children had 2, 5 had 3, and only 3 children had 4 predictors, implying ≤ 40% probability of infectious arthritis in 20 (71%) children. CONCLUSIONS: Because of the overlapping features of K kingae arthritis of the hip and transient synovitis in children younger than 3 years of age, Kocher predictive algorithm is not sensitive enough for differentiating between these 2 conditions. To exclude K kingae arthritis, blood cultures and nucleic acid amplification assay should be performed in young children presenting with irritation of the hip, even in the absence of fever, leukocytosis, or a high Kocher score.

Blood culture diagnostic yield in a paediatric emergency department.

OBJECTIVES: Blood culture (BC) is one of the most commonly used microbiological tests in the paediatric emergency department (PED) despite its lack of immediate diagnostic utility. Our objectives were to uncover the reasons for BC in the PED, to review adherence to the current protocol for this technique, and to analyse the diagnostic yield (DY) of BC in localized bacterial infections. PATIENTS AND METHODS: Retrospective study including patients younger than 18 years with a BC obtained in the PED of a tertiary care hospital in 2011. Patients with bacteraemia risk factors (immunosuppressant condition, long-term vascular catheter, prosthetic valve or ventriculoperitoneal shunt, and hospitalization or aggressive diagnostic or therapeutic procedure in the previous week) were excluded. RESULTS: Two thousand and sixty-two BCs were included. Fever without source (FWS) (34.3%) and pneumonia (10.1%) were the main indications for BC. Twenty-five per cent of BCs did not adhere to protocol: FWS (115 cases), mononucleosic syndrome (83 cases) and acute gastroenteritis (78 cases) represented half of these. The global DY by BC was 2.0%. Streptococcus pneumoniae was the main isolated microorganism (41.4%) and pneumonia was the main associated pathology (22%). All of the BCs with non-adhered-to protocol were negative. All of the BCs obtained for noncomplicated bacterial skin and soft tissue infection were negative. CONCLUSION: FWS is the main reason for BC in the PED. One-quarter of the BCs were not indicated, with the DY null in these cases. Due to the low DY in certain localized bacterial infections, a strict individualized ordering of BC in these cases should be considered.

Prospective surveillance study of blood stream infections associated with central venous access devices (port-type) in children with acute leukemia: an intervention program.

The use of intensive chemotherapy and central devices has improved patients survival, but it is associated with catheter-related blood-stream infections (CRBSI). An educational program was instituted for preventing CRBSI occurrence in acute leukemia pediatric patients having totally implanted central devices. The Centers of Disease Control and Prevention criteria were used as definition for CRBSI. Data collected were age, sex, diagnosis, chemotherapy, inpatient versus outpatient, microbiological data, risk factors, social risk score, and treatment performed. CRBSI rate decreased from 6.7 to 3.7/1000 catheter-days with preventive measures (P=0.05). A further decrease to 1.5/1000 catheter-days was reached after the intensification of the educational program (P=0.01). Severe neutropenia at the time of catheter insertion was related to CRBSI and to infection recurrence (P<0.05). Most of the episodes occurred during induction chemotherapy. Thirty-six CRBSI episodes occurred in 25 of 73 patients. The most frequent microorganism isolated was Staphylococcus spp. Antibiotherapy was successful in 83.3% of episodes. Six patients needed a central venous access device replacement. Our intervention program was successful to decrease the CRBSI rates and its intensification allowed a further decrease, approaching reported rates in this setting. Severe neutropenia at the time of central venous access device insertion was related to CRBSI occurrence and recurrence.

Pneumococcal serotypes causing acute otitis media among children in Barcelona (1992-2011): emergence of the multiresistant clone ST320 of serotype 19A.

BACKGROUND: There is scarce information about changes in serotypes and clonal types of Streptococcus pneumoniae causing acute otitis media (AOM) in recent years, particularly in European countries. METHODS: Pneumococcal serotypes and clones from S. pneumoniae strains isolated from children with AOM who were attended at Hospital Sant Joan de Déu, Barcelona (1992 to 2011), were studied. Heptavalent pneumococcal conjugate vaccine (PCV7) was introduced in June 2001. We defined 3 periods: prevaccine period 1992 to 2001, early vaccine period 2002 to 2006 and late vaccine period 2007 to 2011. RESULTS: There were 376 pneumococcal strains causing AOM, and 373 (99.2%) of them were serotyped. AOM caused by PCV7 serotypes declined significantly: 161 of 245 (65.7%) episodes in 1992 to 2001 versus 22 of 67 (32.8%) in 2002 to 2006 versus 8 of 61 (13.1%) in 2007 to 2011 P < 0.001. In the last period (2007 to 2011), the potential serotype coverage for the PCV10 was 16.4% and for the PCV13 was 68.9% (P < 0.001). Serotype 19A increased from 5.7% in 1992 to 2001 to 42.6% in 2007 to 2011 (P < 0.001). Among strains with penicillin minimal inhibitory concentration ≥0.12 µg/mL (n = 241), serotype 19A rose from 2.3% in the first period to 57.9 % in the last period (P < 0.001). The clonal-type ST320 was initially detected in 2005, and in the period 2007 to 2011, the ST320 was found in 72.7% of nonsusceptible serotype 19A isolates. CONCLUSIONS: Among children with AOM, a rapid expansion of the multiresistant clone ST320 expressing serotype 19A has been observed in Barcelona. The implementation of PCV13, which includes this serotype, may decrease the prevalence of AOM and reduce antimicrobial resistance.

Pneumococcal carriage in children attending a hospital outpatient clinic in the era of pneumococcal conjugate vaccines in Barcelona.

Between April 2004 and March 2006 an oropharyngeal swab was obtained from 502 asymptomatic children, aged 6 months to 6 years, at a tertiary children's hospital outpatient department to assess the pneumococcal colonisation rate, risk factors, serotype distribution and antimicrobial susceptibility. Only 126 (25.3%) children had received ≥ 1 dose of PCV7. The pneumococcal carriage rate was 23.5%. Carrier rates were significantly higher in children aged ≥ 24 months and children attending daycare center. Thirty six (31.0%) of the isolates were contained in PCV7, 39 (33.6%) in PCV10 and 62 (53.4%) in PCV13. Forty-four strains (37.9%) were resistant to penicillin. Vaccine serotype (VT) strains were more likely to be penicillin-nonsusceptible S. pneumoniae than non-PCV7 serotype (NVT) strains (66.7% vs. 21.6%; P < 0.001). In our pediatric population, NVT were predominant among pneumococcal carriers whereas antibiotic resistance was significantly associated with VT. PCV13 can substantially increase the serotype coverage of S.pneumoniae in healthy carriers.

Direct detection of Streptococcus pneumoniae in positive blood cultures by real-time polymerase chain reaction.

We developed a real-time polymerase chain reaction specific for Streptococcus pneumoniae to be applied directly from blood culture bottles without previous DNA extraction step. For the 128 blood culture bottles tested, the assay had 94% and 98.4% sensitivity and specificity, respectively. This assay provides rapid and accurate identification of this pathogen.

Pediatric parapneumonic pleural effusion: epidemiology, clinical characteristics, and microbiological diagnosis.

BACKGROUND: In recent years an increase in the incidence and severity of parapneumonic pleural effusion (PPE) in pediatric populations has been observed. Streptococcus pneumoniae remains the main causal agent. New molecular and antigen techniques have increased the microbiological diagnosis of this pathology. OBJECTIVES: To describe the epidemiology and clinical characteristics of PPE in our population. PATIENTS AND METHODS: Prospective study of patients under the age of 18 years admitted for PPE in a tertiary-care pediatric hospital in Barcelona (Spain) between September 2003 and December 2006. RESULTS: One hundred ninety cases of PPE were diagnosed. The annual incidence of PPE in the population under 18 years of age increased from 19.9 cases per 100,000 in 2004 to 35.2 per 100,000 in 2006. S. pneumoniae was the main causal agent identified: 82.9% of the 21.6% patients with positive culture. Non-vaccine serotypes (NVS) predominated (81.5%), and serotype 1 was responsible for 38.5% of cases. The use of polymerase chain reaction (PCR) test to detect S. pneumoniae increased etiological diagnosis from 21.6% to 42.1%. Antigen assays used to detect pneumococcus in pleural fluid demonstrated 87.9% sensitivity and 100% specificity when PCR was used as the gold standard. CONCLUSIONS: There has been an increase in the incidence of PPE that parallels the increase in CAP. S. pneumoniae remains the principal causal agent, and NVS clearly predominate. The use of PCR to detect S. pneumoniae substantially increases etiologic diagnosis. The use of antigen assays to detect pneumococcus in pleural fluid is a quick and sensitive diagnostic method, and thus a valid alternative to PCR.

Emergence of invasive pneumococcal disease caused by multidrug-resistant serotype 19A among children in Barcelona.

OBJECTIVE: To describe the epidemiology of invasive pneumococcal disease (IPD) caused by Streptococcus pneumoniae serotype 19A. METHODS: We studied all children and adolescents with IPD caused by serotype 19A who were admitted to a Children's Hospital in Barcelona (1997-2007). Serotyping, antibiotic susceptibility and clonal analysis were performed. RESULTS: Comparing the pre-vaccine period (1997-2001) with the early vaccine period (2002-2004) and the late vaccine period (2005-2007) there was an increase of IPD caused by serotype 19A: 1 of 58 episodes (1.7%) vs. 8 of 54 episodes (14.8%) vs. 27 of 123 episodes (21.9%), respectively (P = 0.002). All S. pneumoniae serotype 19A isolated in the pre-vaccine and early vaccine periods (n = 9) were penicillin susceptible, while in the late vaccine period, 12 of 27 (44%) were penicillin nonsusceptible (P = 0.01). A clonal analysis revealed 15 different sequence types (STs) expressing serotype 19A. 10 of them were preexisting STs associated with serotype 19A including the multidrug-resistant ST320 and ST276. CONCLUSION: There was an increase of IPD caused by S. pneumoniae serotype 19A which was mainly related with the emergence of preexisting clones several of them closely related with international multidrug-resistant clones. These results should be considered when selecting the new conjugate pneumococcal vaccines.

Polymerase chain reaction for diagnosis and serogrouping of meningococcal disease in children.

A prospective study was performed including all children younger than 18 years with the clinical diagnosis of invasive meningococcal disease (IMD) hospitalized at the University Hospital Sant Joan de Déu in Barcelona, Spain, from January 2001 to December 2006. During the study period, 168 meningococcal disease cases were reported. Microbiologic confirmation was obtained in 118 cases. Forty-six (38.9%) of 118 cases were only detected by polymerase chain reaction (PCR); 6 patients were culture positive and PCR negative (5%). Serogroup B predominated in the 6-year period with 83.1% of the strains. A significant decrease in serogroup C was observed in the last 3 years of the study (P=0.029), and less common serogroups, such as serogroup A and W135, emerged. Serogroup distribution of patient diagnoses only by real-time PCR showed a similar distribution: serogroup B, 85.7%; serogroup C, 7.1%; and nontypeable serogroups, 7.1%. In conclusion, real-time PCR is more rapid and sensitive than culture for diagnosis and serogrouping of IMD.

Mastoïditis aguda: estudi clínic i microbiològic de 116 casos / No disponible

Objectiu. Estudi de les característiques clíniques i microbiològiques de les mastoïditis agudes al nostre medi. Investigació de la influència de l'ús i l'abús d'antibiòtics en l'otitis mitjana en la freqüència i la gravetat de les mastoïditis.Mètode. Estudi retrospectiu de 116 casos de mastoïditisaguda diagnosticats a l'Hospital Sant Joan de Déu durantun període de 5 anys (1996-2000).Resultats. La mitjana d'edat va ser d'1.8 anys, amb unrang de 2 mesos a 15 anys d'edat (56 % de sexe masculí).La incidència va ser més gran els darrers 2 anys. El 61% presentaven otitis mitjana aguda i el 62% estaven rebentantibiòtic. Noranta set nens presentaven eritema i edemaretroauricular, 90 desplaçament del pavelló auricular i 84 febre. Es va fer hemocultiu a 65 pacients (positiu en 3 casos) i cultiu de secreció òtica a 58 (positiu en 25 pacients). El germen aïllat més sovint va ser el pneumococ (14 casos), principalment els serotips 6B i 19. El percentatge d'aïllament bacterià va ser més alt en pacients no tractats prèviament (52%) que en pacients tractats (36.4%). Les cefalosporines van ser el tractament d'elecció en 105 pacients. Es va fer miringotomia en 48 pacients. Van requerir mastoidectomia 11 pacients. Les mastoïditis més greus es van observar en pacients amb tractament antibiòtic previ.Conclusions. La incidència de mastoïditis aguda estàaugmentant al nostre medi i en aquest estudi són més greus en pacients tractats prèviament. El pneumococ és el principal microorganisme implicat i la majoria de soques estan incloses a la vacuna heptavalent. En tots els casos de mastoïditis aguda s'hauria de fer miringotomia per tal de poder obtenir el microorganisme implicat i el seu antibiograma

No disponible

[Increasing methylase-mediated resistance to macrolides in Streptococcus pyogenes in a children's hospital in Barcelona (Spain)]. / Aumento de la resistencia a macrólidos mediada por metilasas en Streptococcus pyogenes en un hospital pediátrico de Barcelona.

INTRODUCTION: The genetic mechanisms and changes in resistance of Streptococcus pyogenes to clarithromycin and clindamycin were studied in 480 strains from a children's hospital in Barcelona (1996-2003). RESULTS: There was a progressive increase of strains with the MLSB phenotype (55.6% of resistant strains in 2002) and a relative decrease in the M phenotype. The overall rate of macrolide resistance was 29.8%, with an increase from 27.4% in the 1996-2001 period to 35.8% in the 2002-2003 period. The MefA gene was detected in M phenotype strains, the ermB gene in constitutive MLSB strains and the ermTR gene in some inducible MLSB strains. CONCLUSION: The increase of the resistance and the changes in the implied mechanisms reduce the effectiveness of macrolides and clindamycin as an alternative treatment.