Early diagnosis of diabetic retinopathy in primary care / Diagnóstico temprano de retinopatía diabética en el primer nivel de atención

Objective: To evaluate the impact of a strategy for early detection of diabetic retinopathy in patients with type 2 diabetes mellitus (DMT2) in Quintana Roo, México. Methods: Study transversal, observational, prospective, analytical, eight primary care units from Mexican Social Security Institute in the northern delegation of the State of Quintana Roo, Mexico were included. A program for early detection of diabetic retinopathy (DR) in adult 376,169 was designed. Were diagnosed 683 cases of type 2 diabetes, in 105 patients randomized was conducted to direct ophthalmoscopy were subjected to a secondary hospital were assigned. Will determine the degree of diabetic retinopathy and macular edema was performed. Results: In population were 55.2% female, mean age 48+11.1 years, 23.8 % had some degree of DR, 28.0% with mild non- proliferative diabetic retinopathy 48.0 % moderate 16.0% and severe and 8.0% showed proliferative diabetic retinopathy. Those over age 30 are 2.8 times more risk of developing DR, OR= 2.8; 95%CI: 0.42-18.0, and OR= 1.7; 95%CI: 1.02-2.95 women. Conclusions: The implementation of programs aimed at the early detection of debilitating conditions such as diabetic retinopathy health impact beneficiaries, effective links between primary care systems and provide second level positive health outcomes for patient diseases.

Objetivo: Evaluar el impacto de una estrategia para la detección temprana de Retinopatía Diabética en pacientes con Diabetes Mellitus tipo 2 (DM2) en Quintana Roo. Métodos: Estudio Transversal, observacional, prospectivo, analítico. En Ocho unidades de primer nivel de atención de la delegación Norte del Estado de Quintana Roo, México del Instituto Mexicano del Seguro Social. Se diseñó un programa de detección oportuna de retinopatía diabética en 376,169 adultos, se realizó el diagnóstico de 683 casos de DM2, de forma aleatoria se asignaron 105 pacientes a quienes se les practicó oftalmoscopia directa en un hospital de segundo nivel. Se realizó la determinación del grado de retinopatía diabética y edema macular. Resultados: En la muestra predominaron las mujeres: 55.2%, edad promedio de 48+11.1 años, el 23.8% presentó algún grado de DR, 28.0% con retinopatía diabética no proliferativa leve (DRnPL), 48.0% moderada (DRnPM), 16.0% Severa (DRnPS) y el 8.0% presento Retinopatía diabética proliferativa (DRP). Los mayores de 30 años tuvieron 2.8 veces más riesgo de desarrollar DR, OR 2.8; IC95%: 0.42-18.0 al igual que las mujeres OR= 1.7; IC95%: 1.02-2.95. Conclusiones: La realización de programas dirigidos a la detección oportuna de enfermedades incapacitantes como la retinopatía diabética tienen impacto en la salud de los derechohabientes, la vinculación efectiva entre los sistemas de atención primaria y segundo nivel ofrecen resultados favorables para la salud de los pacientes.

Antigen sandwich ELISA predicts RT-PCR detection of dengue virus genome in infected culture fluids of Aedes albopictus C6/36 cells.

Antigen detection by sandwich ELISA was evaluated to predict RT-PCR detection of dengue viral genome in infected culture fluid of Aedes albopictus clone C6/36 cells. Serum specimens collected from dengue patients within 5 days from onset of fever in 2 hospitals in Metro Manila, Philippines, were inoculated into C6/36 cells, and incubated at 28 degrees C. A total of 282 infected culture fluid specimens were harvested and examined by sandwich ELISA and RT-PCR to detect dengue viral antigen and genome, respectively. In the sandwich ELISA, the P/N ratio was calculated by dividing optical density (OD) of a given test specimen by the OD of the standard negative specimen. Samples with a P/N ratio > or = 4.001 were positive for viral genome detection by RT-PCR. The sensitivity and specificity of antigen sandwich ELISA with RT-PCR as the standard, were 90.4% and 100%, respectively. Although antigen sandwich ELISA is less sensitive than RT-PCR, its usefulness lies in its capability to screen a large number of samples at a minimum cost, especially during an outbreak. Samples that meet a set cutoff value can undergo confirmation by RT-PCR for further epidemiological studies.

Reacción en cadena de la polimerasa para la detección rápida y determinación del serotipo de virus del dengue en muestras clínicas / Polymerase chain reaction for rapid detection and serotyping of dengue viruses in clinical samples

El trabajo que aquí se presenta describe las ventajas de usar la reacción en cadena de la polimerasa con transcriptasa inversa (RCP-TI) para detectar e identificar con rapidez virus del dengue en muestras clínicas. Se sometieron directamente a RCP-TI 27 muestras obtenidas de pacientes con fiebre de dengue y fiebre hemorrágica de dengue durante epidemias en Colombia, Nicaragua y Panamá. El ADN de cadena doble obtenido con la RCP-TI se identificó mediante una segunda amplificación (RCP de anidación) utilizando cebadores específicos para cada tipo de virus, aislamiento vírico e inmunofluorescencia indirecta (IFI) y con electroinmunoensayo enzimático detector de anticuerpos IgM contra el virus del dengue. El genoma vírico amplificado se detectó e identificó en un máximo de 8 horas. Los parámetros calculados para hacer el diagnóstico por RCP-TI, usando el aislamiento vírico y la IFI como estándar de oro, fueron una sensibilidad de 100%; una especificidad de 78%; un valor predictivo positivo de 69% y un valor predictivo negativo de 100%. Cabe notar que dos de los especímenes que dieron resultados positivos a la prueba de RCP-TI anidada y negativos al aislamiento vírico mostraron anticuerpos específicos de tipo IgM. Los resultados de la RCP-TI en general mostraron una estrecha concordancia con los del aislamiento vírico, lo cual sugiere que la RCP es un procedimiento que facilita enormemente el diagnóstico rápido y temprano del dengue.

This study describes the benefits of using reverse transcriptase polymerase chain reaction (RT-PCR) for the rapid detection and typing of dengue virus in clinical samples. Twenty-seven serum specimens from patients with dengue fever and dengue hemorrhagic fever in Colombia, Nicaragua, and Panama were directly subjected to RT-PCR for the detection of dengue virus. The resulting double-stranded DNA product was typed by a second round of PCR amplification (nested PCR) with type specific primers, viral culture/indirect immunofluorescence (IIF), and enzyme-linked electroimmunoassay for IgM anti-dengue antibodies. The amplified virus genome was detected and typed within 8 hours. Nested RT-PCR, using viral culture and IIF as the gold standard, showed 100% sensitivity; 78% specificity; 69% positive predictive value, and 100% negative predictive value. It is noteworthy that two of the specimens whose results were positive with nested RT-PCR and negative with viral culture showed specific IgM antibodies. The results of the RT-PCR were in close agreement with those obtained through viral culture. This suggests PCR can greatly facilitate the rapid and early diagnosis of dengue infection.