[Importance of genetics in osteoartrosis]. / Importancia de la genética en la osteoartrosis.

INTRODUCTION: The study of our genome has played an important role in the field of personalized medicine and clinical practice becoming a useful tool to assist the medical community in the early diagnosis and treatment of countless diseases; osteoarthritis (OA) is a complex chronic degenerative joint disease, despite the high prevalence of this disease and its great impact on public health, little is currently known about its etiology and risk of progression. The purpose of this review is to show the advances in genetics in the study of osteoartrosis. METHODS: The present is a review of the literature of the different aspects in which genetics has developed in the study of osteoartrosis, its scopes and its possible impact on prevention and treatment. CONCLUSION: The identification of a high number of candidate genes confirms the complex nature of the disease, it seems clear that the degree of expression of different genes is altered between an arthrosic patient and a healthy one. A deeper understanding of the link between the entire genome sequence and the association with well-characterized OA phenotypes will enable the development of biomarkers, report the risk of disease progression and allow better guidance of treatments.

INTRODUCCIÓN: El estudio de nuestro genoma ha jugado un papel importante en el campo de la medicina personalizada y la práctica clínica, lo que la convierte en una herramienta útil para ayudar a la comunidad médica en el diagnóstico y tratamiento temprano de innumerables enfermedades. La osteoartrosis (OA) es una enfermedad articular degenerativa crónica compleja; a pesar de su alta prevalencia y gran impacto en la salud pública, actualmente se sabe poco sobre su etiología y riesgo de progresión. El objeto de la presente revisión es mostrar los avances de la genética en el estudio de la osteoartrosis. MÉTODOS: Revisión de la literatura sobre los diferentes aspectos en donde la genética se ha desarrollado en el estudio de la osteoartrosis, sus alcances y sus posibles repercusiones en la prevención y tratamiento. CONCLUSIÓN: La identificación de un elevado número de genes candidatos nos confirma la compleja naturaleza de la enfermedad, parece claro que el grado de expresión de diferentes genes está alterado entre un paciente artrósico y uno sano. Una comprensión más profunda del vínculo entre la secuencia de todo el genoma y la asociación con fenotipos bien caracterizados de la OA, permitirá el desarrollo de biomarcadores, informar el riesgo de progresión de la enfermedad y permitir una mejor orientación de los tratamientos.

Effects of amoxicillin/clavulanate or azithromycin on nasopharyngeal carriage of Streptococcus pneumoniae and Haemophilus influenzae in children with acute otitis media.

The effect of antibiotic therapy on nasopharyngeal colonization by Streptococcus pneumoniae and Haemophilus influenzae was evaluated in children diagnosed with acute otitis media. Children were randomly assigned to receive either amoxicillin/clavulanate or azithromycin therapy, and nasopharyngeal swabs were obtained for culture before and after starting therapy. Amoxicillin/clavulanate therapy eradicated or suppressed all strains of S. pneumoniae susceptible to penicillin, 75% of strains with intermediate resistance, and 40% of strains resistant to penicillin. Azithromycin therapy cleared two-thirds of azithromycin-susceptible strains of S. pneumoniae but none of azithromycin-nonsusceptible strains. Selection for antibiotic-resistant strains in individual children was not observed in children who received amoxicillin/clavulanate therapy but was observed in 2 children who received azithromycin therapy. Carriage of H. influenzae was also reduced by antimicrobial therapy but more so by amoxicillin/clavulanate. Antibiotic therapy does not directly increase the number of resistant strains in the population but, by eradicating susceptible strains, allows greater opportunity for carriage and spread of resistant strains.

Increased carriage of resistant non-pneumococcal alpha-hemolytic streptococci after antibiotic therapy.

OBJECTIVE: We compared colonization and resistance rates of non-pneumococcal alpha-hemolytic streptococci (AHS) and Streptococcus pneumoniae in children receiving antibiotic therapy for acute otitis media. STUDY DESIGN: Between December 1997 and September 1998, children 6 months to 6 years of age, diagnosed with acute otitis media were randomly assigned to receive amoxicillin/clavulanate (Augmentin) 45 mg/kg/d in 2 divided doses for 10 days or azithromycin (Zithromax), 10 mg/kg, once on the first day, followed by 5 mg/kg daily for 4 days. Nasopharyngeal swabs for culture were obtained before and at 2 weeks and 2 months after the start of therapy. Streptococci were identified by species, and antibiotic susceptibility was determined by the epsilometric test. RESULTS: One hundred six children completed the 2-week follow-up and 2-month follow-up, respectively. The nasopharyngeal carriage rate of non-pneumococcal AHS increased from 14% before treatment to 32% at the 2-week follow-up (P =.02) and was similar in both treatment groups. In contrast, the carriage of S pneumoniae decreased from 51% before therapy to 27% at the 2-week follow-up (P =.002). The carriage of penicillin-resistant AHS strains (minimum inhibitory concentration > 1 microg/mL) increased from 9% before treatment to 26% at 2 weeks and 36% at 2 months. CONCLUSIONS: Amoxicillin/clavulanate and azithromycin therapy resulted in increased isolation of nasopharyngeal non-pneumococcal AHS, many of which were multidrug-resistant, in contrast to a decrease in pneumococcal carriage. This suggests that the competitive balance between these 2 groups of organisms was disturbed as a result of differential antibiotic susceptibility. The importance of drug-resistant AHS as a reservoir for resistance genes for S pneumoniae warrants further investigation.