Difteria en Venezuela: análisis de las manifestaciones clínicas y evolución de una serie de casos

Objetivo: Analizar las manifestaciones clínicas y evolución de los casos sospechosos o confirmados de Difteria en Venezuela. Materiales y Métodos: Se realizó un estudio prospectivo, observacional, descriptivo, longitudinal y multicentrico en los estados Anzoátegui, Bolívar, Carabobo, Distrito Capital, Lara, Mérida, Miranda y Zulia, se siguieron 48 pacientes sospechosos o confirmados para difteria y se describieron sus características clínicas. Resultados: 54,2 % fueron de sexo femenino, 2 de ellas embarazadas, 1 de ellas falleció. La localización más frecuente de lesiones fue la faríngea, sin embargo se observaron otras como la tonsilar, laringotraqueal, nasal y cutánea. Todos los pacientes recibieron antibióticos pero solo 32 toxina antidiftérica. Solo 11 pacientes tenían esquema vacunal completo y 18 presentaron complicaciones. El 18,8 % de la muestra falleció y el resto egresó sin secuelas. Conclusiones: El brote de difteria en Venezuela sigue activo, las cifras de pacientes afectados invitan a implementar estrategias de control a través de la inmunización de susceptibles, erradicación de portadores asintomáticos, diagnóstico temprano, reporte obligatorio, atención y manejo adecuado de los infectados.

Objective: To analize the clinical manifestations and evolution of suspected or confirmed cases of Diphtheria in Venezuela. Methods: A prospective, observational, descriptive, longitudinal and multicentric study was conducted in the Venezuelan's states of Anzoategui, Bolivar, Carabobo, Capital District, Lara, Merida, Miranda and Zulia. The time 1 of the investigation was at the hospital admission and the final time was at discharge. During the hospitalization, the follow-up was performed. Results: 48 patients were followed and all of them had suspected or confirmed Diphtheria. 45,5 % were men and 54.2 % were female, 2 of them were pregnant, and 1 of them died. The most frequent location of lesions was the pharyngeal, however other location were observed such as tonsillar, laryngotracheal, nasal and cutaneous. All patients received antibiotics but only 32 diphtheria antitoxin. Only 11 patients had a complete vaccination scheme and 18 (36 %) had complications. 18.8 % of the sample died and the rest withdrew without sequelae. Conclusions: The diphtheria outbreak in Venezuela is still active, the number of affected patients invite to implement strategies of control through the immunization of susceptibles, eradication of asymptomatic carriers, early diagnosis, mandatory reporting, care and adequate management of the infected.

Toxicidad de memantina intravítrea en retina de conejos / Intravitreal memantine retinal toxicity in rabbits

OBJETIVO: Valorar histopatológicamente si existe toxicidad en la retina de conejos, posterior a la aplicación intravítrea de memantina. MÉTODOS: Se utilizaron 16 ojos de 16 conejos raza Nueva Zelanda de 3 kg, divididos en 4 grupos de 4 conejos cada uno. Al grupo A se le aplicó una dosis de 70 ng/ml de memantina intravítrea, al grupo B se le aplicó una dosis de 150 ng/ml de memantina intravítrea, al grupo C se le aplicó una dosis de 400 ng/ml de memantina intravítrea, y al grupo D se le aplicó 1 ml de solución salina balanceada. Se enucleó el ojo inyectado en la mitad de cada grupo a los 15 días, y el resto del grupo se enucleó a los 30 días posterior a la inyección. Posterior a la enucleación, cada ojo fue colocado en formaldehido al 10%. Se realizó análisis histopatológico a cada uno de los ojos enucleados. Los animales fueron tratados de acuerdo a los estatutos de la Association for Research on Vision and Ophthalmology (ARVO). RESULTADOS: Los grupos A, B y D no presentaron alteraciones histopatológicas tras 15 y 30 días de enucleación. El grupo C presentó alteración a nivel de la capa de fotorreceptores a los 15 y 30 días posterior a la enucleación. CONCLUSIONES: La memantina intravítrea a dosis de 70 mg/dl y 150 mg/dl no es tóxica a nivel estructural en la retina. La memantina a dosis de 400 mg/dl es tóxica a nivel estructural en la retina. La memantina podría ser considerada en el futuro para el tratamiento de distrofias de retina. Diversos estudios deberán ser realizados al respecto

OBJECTIVE: To histologically evaluate whether the intravitreal application of memantine produces retinal toxicity in rabbits. METHODS: A cross-sectional design, experimental, descriptive study was performed on 16 eyes of 16 New Zealand rabbits of 3 kg, divided in 4 groups of 4 rabbits. A dose of 70 ng/ml of intravitreal memantine was administered in Group A, a dose of 150 ng/ml in Group B, a dose of 400 ng/ml in Group C, and Group D received 1 ml of balanced salt solution. The injected eye of half of each group was enucleated 15 days after the injection, and the rest within 30 days after injection. Following enucleation, each eye was placed in 10% formaldehyde. Histopathological analysis was performed on all enucleated eyes. The animals were treated according to the guidelines of the Association for Research on Vision and Ophthalmology (ARVO). RESULTS: Groups A, B and D did not show any histopathological changes after their enucleation at 15 and 30 days. Group C showed changes in the photoreceptor layer after enucleation at 15 and 30 days. CONCLUSIONS: In our study, it was observed that memantine concentrations at 70 ng/ml and 150 ng/ml are safe when administered intravitreally; however, doses of 400 ng/ml produced retinal structural changes. This research should continue to assess its clinical usefulness

Intravitreal memantine retinal toxicity in rabbits.

OBJECTIVE: To histologically evaluate whether the intravitreal application of memantine produces retinal toxicity in rabbits. METHODS: A cross-sectional design, experimental, descriptive study was performed on 16 eyes of 16 New Zealand rabbits of 3 kg, divided in 4 groups of 4 rabbits. A dose of 70 ng/ml of intravitreal memantine was administered in Group A, a dose of 150 ng/ml in Group B, a dose of 400 ng/ml in Group C, and Group D received 1 ml of balanced salt solution. The injected eye of half of each group was enucleated 15 days after the injection, and the rest within 30 days after injection. Following enucleation, each eye was placed in 10% formaldehyde. Histopathological analysis was performed on all enucleated eyes. The animals were treated according to the guidelines of the Association for Research on Vision and Ophthalmology (ARVO). RESULTS: Groups A, B and D did not show any histopathological changes after their enucleation at 15 and 30 days. Group C showed changes in the photoreceptor layer after enucleation at 15 and 30 days. CONCLUSIONS: In our study, it was observed that memantine concentrations at 70 ng/ml and 150 ng/ml are safe when administered intravitreally; however, doses of 400 ng/ml produced retinal structural changes. This research should continue to assess its clinical usefulness.

Epidemiology of Streptococcus pneumoniae and Staphylococcus aureus colonization in healthy Venezuelan children.

Streptococcus pneumoniae and Staphylococcus aureus cause significant morbidity and mortality worldwide. We investigated both the colonization and co-colonization characteristics for these pathogens among 250 healthy children from 2 to 5 years of age in Merida, Venezuela, in 2007. The prevalence of S. pneumoniae colonization, S. aureus colonization, and S. pneumoniae-S. aureus co-colonization was 28%, 56%, and 16%, respectively. Pneumococcal serotypes 6B (14%), 19F (12%), 23F (12%), 15 (9%), 6A (8%), 11 (8%), 23A (6%), and 34 (6%) were the most prevalent. Non-respiratory atopy was a risk factor for S. aureus colonization (p = 0.017). Vaccine serotypes were negatively associated with preceding respiratory infection (p = 0.02) and with S. aureus colonization (p = 0.03). We observed a high prevalence of pneumococcal resistance against trimethoprim-sulfamethoxazole (40%), erythromycin (38%), and penicillin (14%). Semi-quantitative measurement of pneumococcal colonization density showed that children with young siblings and low socioeconomic status were more densely colonized (p = 0.02 and p = 0.02, respectively). In contrast, trimethoprim-sulfamethoxazole- and multidrug-resistant-pneumococci colonized children sparsely (p = 0.03 and p = 0.01, respectively). Our data form an important basis to monitor the future impact of pneumococcal vaccination on bacterial colonization, as well as to recommend a rationalized and restrictive antimicrobial use in our community.