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Evidence of the effectiveness of the tests used to diagnose Helicobacter pylori (H. pylori) in primary healthcare is limited. This cross-sectional study aims to assess the accuracy of tests used for to diagnose H. pylori infection in primary care patients and its relationship with gastroduodenal pathologies. Over 12 months, 173 primary care patients with dyspeptic symptoms were referred for upper gastrointestinal endoscopy to obtain gastric biopsies, and venous blood was extracted from them. H. pylori infection was detected using a rapid urease test (RUT), real-time polymerase chain reaction (RT-PCR), H. pylori-IgG ELISA, and Western blot (WB). The culture and histological findings were used as the reference standard for H. pylori infection. H. pylori prevalence was 50%. There were no significant differences between men and women overall or by age group. The presence of H. pylori was associated with chronic moderate gastritis and its absence with chronic inactive gastritis, as well as the combination of gastritis and gastric lesions (p < 0.05). RUT and ELISA H. pylori -IgG tests showed the highest overall performance (accuracy 98.9% and 84.4%), followed by WB and RT-PCR (accuracy 79.3% and 73.9%). These findings support the notion that combined invasive and noninvasive methods, such as RUT and H. pylori-IgG ELISA, can be a primary diagnostic screening tool for detecting H. pylori among adult dyspeptic patients in Cuba's primary care setting.
RESUMEN
INTRODUCTION Cuba has implemented an effective National Immunization Program since 1962. The schedule, administered primarily to children, comprises 11 vaccines (8 domestically produced) protecting against 13 diseases. In 1999 Cuba launched a national vaccine adverse event surveillance system to monitor and assess the safety of the immunization program, its vaccination procedures and the products administered. OBJECTIVES Describe adverse events following vaccination reported in children aged <16 years in Cuba from 1999 through 2008. METHODS A retrospective descriptive study was conducted of adverse events following vaccination reported from January 1999 through December 2008. Variables used: year, number of adverse events, province, type of vaccine, type and severity of adverse events (common minor, rare, severe), vaccination program errors, number of deaths, and final results of investigations of severe events. Percentages and rates per dose administered were calculated. Adverse event rates were calculated per 100,000 doses administered and by percentages of individual effects among events reported. RESULTS A total of 45,237,532 vaccine doses were administered, and 26,159 vaccine-associated adverse events were reported (overall rate: 57.8 per 100,000 doses). The group aged 0-5 years reported the highest rate of vaccine-associated adverse events (82/100,000 doses). The DTwP vaccine exhibited the highest rate of adverse events. Common minor events were: fever (17,538), reactions at injection site (4470) and systemic side effects (2422). Rare events (by WHO definition) reported were: persistent crying (2666), hypotonic-hyporesponsive episodes (3), encephalopathy (2) and febrile seizures (112). Severe events included: anaphylaxis (2), respiratory distress (1), multiple organ failure (1), sudden death (1), vaccine-associated paralytic poliomyelitis (2), toxic shock syndrome (3), and sepsis (1). The 10 deaths and 3 cases of disability were investigated by an expert commission, which concluded that 8 of the 13 severe events were vaccination-related. CONCLUSIONS Low rates of severe vaccine-associated adverse events observed in this study underline the low risk of vaccination relative to its demonstrated benefits in Cuba. Decision-making for the continued success of the National Immunization Program is supported by reliable information from comprehensive national surveillance with standarized reporting, along with multidisciplinary expert analysis of rare and severe adverse events and program errors. KEYWORDS Immunization; immunization programs; vaccines; vaccination; product surveillance, postmarketing; adverse drug event; communicable disease control; Cuba.
INTRODUCCIÓN Cuba tiene implementado un efectivo Programa Nacional de Inmunización desde 1962. El programa, dirigido principalmente a los niños, incluye 11 vacunas (8 de producción nacional) que protegen contra 13 enfermedades. En 1999, Cuba comenzó un programa de vigilancia de eventos adversos para monitorizar y evaluar la seguridad del programa de inmunización, los procedimientos de vacunación, y los productos utilizados. OBJETIVO Describir los eventos adversos asociados a la vacunación de niños de menos de 16 años, notifi cados en Cuba entre los años 19992008. MÉTODOS Se realizó un estudio descriptivo retrospectivo de los eventos adversos comunicados después de una vacunación, desde enero de 1999 hasta diciembre de 2008. Las variables utilizadas fueron: año, número de eventos adversos, provincia, tipo de vacuna, tipo y gravedad de los eventos adversos (leves y comunes, raros, severos), errores en el programa de vacunación, número de fallecidos y resultados fi nales de la investigación de los eventos severos. Se calcularon los porcentajes y las tasas por dosis aplicadas. Las tasas de eventos adversos se calcularon por 100,000 dosis aplicadas y según el porcentaje de efectos individuales entre los eventos comunicados. RESULTADOS Un total de 45,237,532 dosis de vacunas fueron administradas y se notifi caron 26 159 eventos adversos (tasa total: 57,8 por 100,000 dosis). La tasa más alta de eventos adversos asociados a la vacunación se identifi có en el grupo de 05 años (82/100,000 dosis). La vacuna DTPe (difteria, tétanos y pertusis de células enteras) mostró la tasa más alta de eventos adversos. Los eventos leves comunes fueron: fi ebre (17 538), reacciones en el sitio de inyección (4470) y efectos colaterales a nivel sistémico (2422). Los eventos raros comunicados (según defi nición de la OMS) fueron: llanto persistente (2666), episodios de hipotonía-hipo reactividad (3), encefalopatía (2) y convulsiones febriles (112). Los eventos graves incluyeron: anafi laxia (2), distrés respiratorio (1), síndrome de shock tóxico (3) y sepsis (1). Los 10 casos fallecidos y los 3 con incapacidad fueron investigados por una comisión de expertos, que concluyó que 8 de los 13 eventos severos estuvieron relacionados con la vacunación. CONCLUSIONES Las bajas tasas de eventos adversos graves asociados a la vacunación, observadas en este estudio, subrayan el bajo riesgo de la vacunación con respecto a sus benefi cios en Cuba. La toma de decisiones para mantener exitosamente el Programa Nacional de Inmunización se apoya en la información fi dedigna y en los informes estandarizados suministrados por el exhaustivo sistema de vigilancia nacional, conjuntamente con el análisis, por expertos multidisciplinarios, de los eventos adversos raros y severos y de los errores del programa. PALABRAS CLAVE Inmunización; programas de inmunización, vacunas, vacunación, sistema de vigilancia de productos, eventos adversos, control de enfermedades transmisibles, Cuba