[Evaluation of a carbon 13 breath test for the diagnosis of Helicobacter pylori]. / Evaluación de un test del aliento con carbono 13 para el diagnóstico de Helicobacter pylori.

OBJECTIVE: To evaluate a Chinese-made carbon-13 breath test as a non-invasive diagnostic method for Hp infection in the Peruvian population through the determination of sensitivity, specificity, positive and negative predictive value, positive and negative likelihood ratio, and diagnostic utility. MATERIALS AND METHODS: A cross-sectional and descriptive study was carried out on a secondary database of the Gastroenterology Service of the Cayetano Heredia Hospital and Cayetano Heredia Clinic from November 2017 to August 2018. Patients over 18 years of age who underwent endoscopy were included upper digestive. RESULTS: A sensitivity of 90.3% (95% CI 0.81-0.96), a specificity of 82.5% (95% CI 0.67-0.93), a positive predictive value was found and negative of 90.3% and 82.5%, and positive and negative likelihood ratio of 5.16 and 0.12, respectively. The area under the ROC curve was 0.88 (95% CI: 0.80-0.96). CONCLUSIONS: The carbon 13 breath test is a non-invasive and simple test that provides results quickly. However, it is not possible to recommend the routine use of this test due to the discrepancy between the international and local results obtained. Studies with larger sample sizes, standardized protocols and different manufacturers are suggested to evaluate their performance and characteristics.

Evaluación de un test del aliento con carbono 13 para el diagnóstico de Helicobacter pylori / Evaluation of a carbon 13 breath test for the diagnosis of Helicobacter pylori

RESUMEN Objetivo: Evaluar un test del aliento con carbono 13 de fabricación China como método diagnóstico no invasivo para la infección por Hp en población peruana a través de la determinación de sensibilidad, especificidad, valor predictivo positivo y negativo, likelihood ratio positivo y negativo y utilidad diagnóstica. Materiales y métodos: Se realizó un estudio transversal y descriptivo sobre una base de datos secundaria del Servicio de Gastroenterología del Hospital Cayetano Heredia y Clínica Cayetano Heredia de noviembre de 2017 a agosto de 2018. Se incluyó a pacientes mayores de 18 años sometidos a una endoscopía digestiva alta. Resultados: Se halló una sensibilidad de 90,3% (IC 95% 0,81-0,96), especificidad de 82,5% (IC 95% 0,67-0,93), valor predictivo positivo y negativo de 90,3% y 82,5%, y likelihood ratio positivo y negativo de 5,16 y 0,12, respectivamente. El área bajo la curva ROC fue 0,88 (IC 95%: 0,80-0,96). Conclusiones: El test del aliento con carbono 13 es una prueba no invasiva y sencilla que proporciona resultados de forma rápida. Sin embargo, no es posible recomendar el uso rutinario de esta prueba debido a la discrepancia entre los resultados internacionales y locales obtenidos. Se sugiere realizar estudios con mayores tamaños muestrales, protocolos estandarizados y de diferentes fabricantes para evaluar su rendimiento y características.

ABSTRACT Objective: To evaluate a Chinese-made carbon-13 breath test as a non-invasive diagnostic method for Hp infection in the Peruvian population through the determination of sensitivity, specificity, positive and negative predictive value, positive and negative likelihood ratio, and diagnostic utility. Materials and methods: A cross-sectional and descriptive study was carried out on a secondary database of the Gastroenterology Service of the Cayetano Heredia Hospital and Cayetano Heredia Clinic from November 2017 to August 2018. Patients over 18 years of age who underwent endoscopy were included upper digestive. Results: A sensitivity of 90.3% (95% CI 0.81-0.96), a specificity of 82.5% (95% CI 0.67-0.93), a positive predictive value was found and negative of 90.3% and 82.5%, and positive and negative likelihood ratio of 5.16 and 0.12, respectively. The area under the ROC curve was 0.88 (95% CI: 0.80-0.96). Conclusions: The carbon 13 breath test is a non-invasive and simple test that provides results quickly. However, it is not possible to recommend the routine use of this test due to the discrepancy between the international and local results obtained. Studies with larger sample sizes, standardized protocols and different manufacturers are suggested to evaluate their performance and characteristics.

Characterization of HIV-Associated Neurocognitive Impairment in Middle-Aged and Older Persons With HIV in Lima, Peru.

Background: With widespread use of antiretroviral medications, people living with HIV (PWH) are living longer worldwide, increasing their risk of developing neurocognitive impairment (NCI). The proportion of Peruvians over age 60 is expected to increase to 25% of the population by 2050, including PWH. Therefore, the problem of aging and NCI, especially in the setting of HIV infection, is uniquely pressing. We sought to study the rates of and risk factors associated with NCI among middle-aged and older PWH in Lima, Peru. Materials and Methods: Sociodemographic, medical (infectious and non-infectious), and psychiatric comorbidity and laboratory data were collected. We administered a brief neuropsychological battery evaluating seven cognitive domains affected in HIV-associated NCI and a depression screening. Cognitive test raw scores were converted to T-scores that were demographically adjusted. Descriptive statistics were performed together with regression (unadjusted and adjusted) analyses to determine potential risk factors for NCI among PWH. Results: This was a cross-sectional study in which 144 PWH aged ≥40 years attending a large HIV clinic in Lima, Peru, were recruited from September 2019 to March 2020. Mean age was 51.6 ± 7.7 years, and mean years of education were 14.0 ± 3.1 with 15% females. Median [interquartile range (IQR)] current CD4 and nadir CD4 were 554 (371, 723) and 179 (83, 291), respectively, and 10% currently had AIDS. The prevalence of NCI was 28.5%, and many demonstrated difficulty with attention and working memory (70%). One-quarter of PWH had mild depression or worse on Patient Health Questionnaire 9 (PHQ-9 ≥ 5). In bivariate analyses, neither a depression history nor a higher PHQ-9 score correlated with NCI. No other non-communicable medical or psychiatric comorbidity nor HIV characteristic was predictive of NCI. Having a positive lifetime history of hepatitis B infection, pulmonary tuberculosis, or syphilis increased risk of NCI (PR 1.72; 95% CI 1.04-2.86) in unadjusted analyses, but not in adjusted analyses. Conclusions: NCI among older Peruvians with HIV was found to be highly prevalent with levels consistent with prior reports of HIV-associated NCI worldwide. Common latent HIV-associated co-infections, including latent syphilis, hepatitis B infection, or pulmonary tuberculosis, may increase the risk of NCI among middle-aged and older PWH in Peru.