M. González Sánchez

Serotipos no vacunales emergentes causantes de enfermedad neumocócica invasora en la era de la vacuna 7-valente

INTRODUCTION There has been an increased incidence in invasive pneumococcal disease (IPD) produced by non-vaccine serotype (NVS) of Streptococcus pneumoniae after the introduction of PCV7. Our objective was to describe the epidemiological, clinical and microbiological characteristics of IPD caused by NVS in a tertiary hospital in Madrid. PATIENTS AND METHODS Retrospective (1998-2004) and prospective (2005-2009) study evaluating IPD caused by NVS in children. The study was divided into three periods: P1 (1998-2001) when PCV7 was not commercialized; P2 (2002-2005) with 40% vaccine coverage among children; and P3 (2006-2009) when the vaccine was added to the Childhood Immunization Schedule in Madrid. RESULTS We analyzed 155 cases of IPD. One hundred and fifty of these isolates were serotyped (100 were NVS). There was an increase in the prevalence of IPD from P1 (31%) to P2 (54%) and P3 (91%). The most relevant emerging serotypes were 19A, 7F, 1, 5, 3 and 15C. The most significant clinical syndromes produced by some specific serotypes were as follows: lower respiratory tract infection (LRTI) by serotypes 1, 3, 5 and 15C; LRTI, primary bacteremia and meningitis by serotype 19A; and primary bacteremia by serotype 7F (66%). The large majority (83.8%) of NVS were sensitive to penicillin. CONCLUSIONS There has been an increased prevalence of IPD caused by NVS since the introduction of PCV7. These changes should prompt the introduction of new pneumococcal vaccines, which include most of the NVS, in the childhood immunization calendar to prevent IPD in children.

Aumento de la incidencia de enfermedad neumocócica invasora producida por el serotipo 19A previo a la introducción de las vacunas neumocócicas ampliadas

OBJECTIVE To describe the epidemiology, clinical syndromes and microbiological characteristics of serotype 19A as the main cause of invasive pneumococcal disease (IPD) in children admitted to a tertiary hospital in Spain. METHODS A retrospective (1998-2004) and prospective (2005-2009) study was conducted on children with IPD produced by serotype 19A. The study was divided into three periods (P): P1 (1998-2001) when PCV7 had not been commercialized; P2 (2002-2005) with 40% vaccine coverage among children; and P3 (2006-2009) when the vaccine was added to the Childhood Immunization Schedule in Madrid. RESULTS A total of 155 isolates of Streptococcus pneumoniae (SP) producing IPD were analysed, with 21 of them being serotype 19A (14%). An increased prevalence of serotype 19A was found: 2/45 cases (4.4%) in P1, 3/41 cases (7.3%) in P2 and 16/69 cases (23.2%) in P3. It occurred mostly in children younger than 2 years (16/21; 76%). This serotype was the main cause of meningitis (5/20; 25%), pleural empyema (3/22; 14%) and bacteraemic mastoiditis (2/4; 50%). Thirteen isolates (61.5%) had an MIC ≥ 0.12μ/ml for penicillin in extra-meningeal infections, and 3 of the 5 isolates causing meningitis (60%) had an MIC ≥ 1μ/ml for cefotaxime. CONCLUSIONS Serotype 19A was the main causal agent of IPD in the PCV7 era (P3), with high antibiotic resistance rates. This serotype was responsible for all types of IPD, being the main cause of meningitis.

Coinfección por Chlamydia y Mycoplasma. Incidencia en nuestro medio

Objetivos Investigar la presencia y determinar la importancia de Chlamydia pneumoniae y Mycoplasma pneumoniae como copatogenos de las neumonias comunitarias en la infancia. Material y metodos Estudio retrospectivo descriptivo, de todos los casos diagnosticados de neumonia por M. pneumoniae en menores de 15 anos, en el servicio de urgencias de pediatria, en el periodo comprendido entre mayo de 1998 y mayo de 2000, investigando aquellos casos en los que se pudo demostrar la coexistencia con C. pneumoniae. Resultados Sobre un total de 242 neumonias diagnosticadas durante este periodo de tiempo, 84 fueron causadas por M. pneumoniae (34,7 %) y 32 por C. pneumoniae (13,22 %); de ellas, 8 casos presentaron coinfeccion por C. pneumoniae y M. pneumoniae. Existio predominio en el sexo masculino 5/8, con una edad media al diagnostico de 7,7 anos. No hubo predominio estacional. Conclusiones Tanto C. pneumoniae como M. pneumoniae son responsables de Neumonia Adquirida en la Comunidad en ninos mayores de 5 anos. A pesar del hecho de que las coinfecciones por C. pneumoniae y M. pneumoniae se acompanan normalmente de agravamiento en el curso de la enfermedad, todos los casos estudiados evolucionaron satisfactoriamente.