RESUMEN
Infective endocarditis (IE) is a life-threatening disease, caused by septic vegetations and inflammatory foci on the surface of the endothelium and the valves. Due to its complex and often indecisive presentation the mortality rate is still about 30%. Most frequently bacterial microorganisms entering the bloodstream are the underlying origin of the intracardiac infection. While the disease was primarily restricted to younger patients suffering from rheumatic heart streptococci infections, new at risk categories for Staphylococcus (S.) aureus infections arose over the last years. Rising patient age, increasing drug resistance, intensive treatment conditions such as renal hemodialysis, immunosuppression and long term indwelling central venous catheters but also the application of modern cardiac device implants and valve prosthesis have led to emerging incidences of S. aureus IE in health care settings and community. The aetiologic change has impact on the pathophysiology of IE, the clinical presentation and the overall patient management. Despite intensive research on appropriate in vitro and in vivo models of IE and gained knowledge about the fundamental mechanisms in the formation of bacterial vegetations and extracardiac complications, improved understanding of relevant bacterial virulence factors and triggered host immune responses is required to help developing novel antipathogenic treatment strategies and pathogen specific diagnostic markers. In this review, we summarize and discuss the two main areas affected by the changing patient demographics and provide first, recent knowledge about the pathogenic strategies of S. aureus in the induction of IE, including available experimental models of IE used to study host-pathogen interactions and diagnostic and therapeutic targets. In a second focus we present diagnostic (imaging) regimens for patients with S. aureus IE according to current guidelines as well as treatment strategies and surgical recommendations.
Asunto(s)
Endocarditis Bacteriana/fisiopatología , Infecciones Estafilocócicas/fisiopatología , Staphylococcus aureus/patogenicidad , Animales , Modelos Animales de Enfermedad , Endocarditis Bacteriana/cirugía , Endocarditis Bacteriana/terapia , Prótesis Valvulares Cardíacas/microbiología , Interacciones Huésped-Patógeno , Humanos , Incidencia , Ratones , Estudios Retrospectivos , Infecciones Estafilocócicas/complicacionesAsunto(s)
Aciclovir/administración & dosificación , Antivirales/administración & dosificación , Farmacorresistencia Viral , Infecciones por VIH/complicaciones , Herpes Genital/tratamiento farmacológico , Herpesvirus Humano 2/aislamiento & purificación , Mutación Missense , Aciclovir/farmacología , Adulto , Antivirales/farmacología , Técnicas de Genotipaje , Herpes Genital/virología , Herpesvirus Humano 2/efectos de los fármacos , Herpesvirus Humano 2/genética , Humanos , Masculino , Recurrencia , Timidina Quinasa/genética , Insuficiencia del Tratamiento , Carga ViralRESUMEN
BACKGROUND: The prevalence of nasopharyngeal colonization with Staphylococcus aureus can reach 20-30% among the population, which can lead to invasive infection. AIM: To investigate the prevalence of colonization among different age groups, and analyse S. aureus strain-specific virulence patterns. METHOD: For analysis of the prevalence of colonization, groups consisting of newborns, healthy volunteers aged 5-60 years, and nursing home residents aged >80 years were examined with nasopharyngeal swabs. After S. aureus was cultured, genetic analysis and phenotypic virulence testing were performed by cell-based assays. FINDINGS: Among 924 volunteers, the overall colonization rate was approximately 30%, with a peak in subjects aged 5-10 years (49%). Neonates and subjects aged >80 years showed different distributions of clonal clusters. Overall, the strains of all age groups exhibited virulence characteristics that can contribute to the development of infection. In particular, the neonatal strains exhibited a high incidence of toxin genes that resulted in increased cytotoxic effects compared with the other strains tested. CONCLUSIONS: Colonizing strains showed a virulence profile in all age groups, which may lead to the establishment of invasive infection. Consequently, decolonization measures could be considered for selected patients depending on the risk of infection.