Giannina Izquierdo

Vancomicina es un antimicrobiano ampliamente utilizado en recién nacidos (RN) hospitalizados, existiendo distintos esquemas de dosificación que recomiendan o no el uso de dosis de carga, dependiendo de edad gestacional (EG), peso y función renal. Objetivo: Evaluar el uso de niveles plasmáticos tras dosis de carga de vancomicina y su impacto en el logro del objetivo .rea bajo la curva/concentración inhibitoria mínima (ABC/CIM) en una unidad de cuidados intensivos neonatales (UCIN). Pacientes y Método: Estudio retrospectivo, descriptivo y observacional en RN hospitalizados entre diciembre 2022 y diciembre 2023, en una UCIN de alta complejidad. Se incluyeron todos los RN con indicación de vancomicina empírico/dirigido y que recibieron dosis de carga con monitorización de concentraciones plasmáticas (Cp) basales, según protocolo local. Se registraron datos demográficos y clínicos. Se consideró falla renal al aumento de creatinina en 0,3 mg/dl en 48 horas y débito urinario ≤ 1 ml/kg/día. Se utilizó el programa PrecisePKⓇ para estimar parámetros farmacocinéticos y el área bajo la curva (ABC). Resultados: Se analizaron 52 Cp de vancomicina, de las cuales el 73,1% alcanzaron valores óptimos entre 10 – 20 mcg/ml, 19,2% Cp resultaron supraterapéuticas (> 20 mcg/ml) y 86% de los pacientes alcanzaron un ABC entre 400 – 600 mg/L. El principal factor de riesgo para Cp supraterapéuticas fue la falla renal previo al tratamiento (p = 0,001). Conclusiones: La dosis de carga de vancomicina logra ABC óptimo en un 86% de los casos. Se sugiere monitorizar la Cp basal después de la dosis de carga especialmente en aquellos pacientes con falla renal.

La infección congénita por citomegalovirus (CMV) es la infección congénita viral más frecuente. Produce importantes secuelas a largo plazo, como la sordera neurosensorial y el retraso psicomotor, con su diagnóstico oportuno y tratamiento antiviral precoz podrían ser reducidas. El desarrollo de guías nacionales o locales para el abordaje sistemático de esta patología, tanto en la mujer embarazada y el feto como en el recién nacido, resultan fundamentales para mejorar los resultados perinatales y a largo plazo, y también para que los profesionales sanitarios tomen conciencia de la importancia de esta patología. En este documento se resume su diagnóstico, seguimiento clínico y tratamiento.

Background: Infants face a high risk of morbidity and mortality from pertussis early in life, leading to the adoption of maternal vaccination. This study aimed to review the characteristics of the maternal pertussis vaccination in Latin American (LATAM) countries and evaluate their impact on pertussis absolute mortality and case fatality rate (CFR) in infants under 1 year old. Methods: LATAM countries with maternal tetanus, diphtheria and acellular pertussis (Tdap) vaccination in their National Immunization Programs were included. Data on pertussis incidence, deaths and cases in <1-year-old; characteristics of Tdap vaccination in pregnancy; and third dose of diphtheria, tetanus and pertussis and Tdap coverage rates were collected and analyzed. The impact on absolute mortality and CFR was assessed by comparing the percentage reduction between 4 years before and after (up to 2019) the Tdap introduction for each country. Results: The LATAM countries included were Argentina, Brazil, Chile, Costa Rica, Colombia, El Salvador, Mexico, Panamá, Paraguay, Peru and Uruguay. Post-Tdap introduction, pertussis incidence declined notably, especially from 2020. The beginning of the maternal Tdap strategy varied, occurring between 2012 and 2019, with a common recommendation at 20 weeks gestation. In most countries, absolute mortality and CFR decreased, though variations ranged from −9.9% to 88.9% and −60.6% to 81.2%, respectively. Tdap and third dose of diphtheria, tetanus and pertussis coverage rates declined by 2021, with rates ranging from 37% to 92% and 58% to 95%, respectively. Conclusion: The characteristics of maternal Tdap vaccination varied across LATAM countries. The vaccine implementation into the National Immunization Program has reduced pertussis cases, deaths and CFR in infants <1-year-old in most countries.

Background: Several screening strategies for identifying congenital CMV (cCMV) have been proposed; however, the optimal solution has yet to be determined. We aimed to determine the prevalence of cCMV by universal screening with saliva pool testing and to identify the clinical variables associated with a higher risk of cCMV to optimize an expanded screening strategy. Methods: We carried out a prospective universal cCMV screening (September/2022 to August/2023) of 2186 newborns, analyzing saliva samples in pools of five (Alethia-LAMP-CMV^®) and then performed confirmatory urine CMV RT-PCR. Infants with risk factors (small for gestational age, failed hearing screening, HIV-exposed, born to immunosuppressed mothers, or p = 0.04). False positives occurred in 0.09% of cases. No significant differences in maternal/neonatal characteristics were observed, except for a higher prevalence among infants born to non-Chilean mothers (p = 0.034), notably those born to Haitian mothers (1.5%, 95% CI 0.31–4.34), who had higher odds of cCMV (OR 6.82, 95% CI 1.23–37.9, p = 0.04). Incorporating maternal nationality improved predictive accuracy (AUC: 0.65 to 0.83). Conclusions: For low-prevalence diseases such as cCMV, universal screening with pool testing in saliva represents an optimal and cost-effective approach to enhance diagnosis in asymptomatic patients. An expanded screening strategy considering maternal nationality could be beneficial in resource-limited settings.

Background Chronic hepatitis-B virus (HBV) infection due to mother-to-child transmission (MTCT) during the perinatal period is an important global health concern. Chile is a low-prevalence country with an increasing migratory inflow from Latin- American countries, with intermediate to high endemic rates of HBV infection, and until 2021, there is no universal maternal screening. This study aimed to evaluate infant outcomes using a risk-based strategy of maternal screening to prevent MTCT of hepatitis B virus (HBV) in a low-prevalence country. Methods This prospective study included infants born to HBsAg-positive women detected using a local risk-based strategy. The exposed infants received immunoprophylaxis (IP) and follow-up to evaluate their clinical outcomes and immune responses through post-serological vaccine testing (PSVT) after completing the three- dose schedule of the HBV vaccine. Results A total of 99 HBsAg-positive mothers were detected. Seventy-six (82%) infants completed the follow-up and had PSVT between 9 and 12 months of age. 55.2% female, the median gestational age was 39 weeks (25–41) and the median birth weight was 3,130g (816–4,400 g). All patients received IP with recombinant HBV vaccine plus hepatitis-B virus immunoglobulin (HBIG) and three doses of the HBV vaccine. There were no cases of HBV infection, and 96% (72) responded to immunization with HBsAg antibodies (anti-HBsAg) >10 UI/ml, with a median level of 799 IU/ml. Conclusions A high-risk strategy can be implemented in countries with non-universal screening for VHB. Timely IP plus high-uptake VHB vaccination in infants born to HBsAg-positive mothers was associated with a high immunogenic response and absence of MTCT.

Universal congenital cytomegalovirus (cCMV) screening in saliva is increasingly recommended. The aim of our study was to correlate the performance of a point-of-care rapid molecular test with CMV real time PCR (CMV RT-PCR) detection, using saliva pool-testing in newborns under a universal screening strategy. Saliva swabs were prospectively collected from newborns < 21 days old and tested by Alethia-LAMP-CMV assay in pools of 5 samples. In positive pools, subjects were tested individually and by saliva and urine CMV RT-PCR. A subset of negative pools were studied with both techniques and viral loads in whole blood were determined in positive patients. From 1,642 newborns included in 328 pools, 8 were confirmed by urine CMV RT-PCR, (cCMV prevalence 0,49%). The PPA and NNA of the pooled saliva Alethia-LAMP-CMV testing were 87,5% and 99,8% with a negative and positive predictive value of 99,9% and 77,7%, respectively. Two false positives were detected (0,12%). A subset of 17 negative pools (85 samples), studied by saliva CMV RT-PCR, showed 100% concordance. Conclusion: CMV pool-testing using a rapid molecular test in saliva proved feasible when compared to PCR gold standards. This strategy could improve cost-effectiveness for cCMV universal neonatal screening, based on the low prevalence of the infection and could be a more affordable approach in less developed regions with reduced detection capacity. What is Known:• cCMV is the most frequent congenital infection and a leading nongenetic cause of sensorineural hearing loss and brain disease. • Universal screening could allow early detection of congenitally infected infants, improving clinical outcome. • Saliva PCR is the preferred and non-invasive test for newborn cCMV screening. What is New: • The feasibility of a universal cCMV screening by pool-testing in saliva using a rapid test in pools of 5 samples. • PPA and NPA were 87,5 and 99,8% compared to CMV PCR in urine. • This strategy could be relevant specially in LMIC where detection capacity is reduced and could improve cost-effectiveness. • cCMV prevalence in our center was 0,49%.

La Sociedad Chilena de Infectología, a través de su Comité de Infecciones Neonatales, en conjunto con la Sociedad Chilena de Obstetricia y Ginecología, proponen un documento de diagnóstico y manejo de la Infección por Citomegalovirus en la Mujer Embarazada y el Recién Nacido. Esta guía aborda el manejo de la infección en el binomio, su enfrentamiento diagnóstico y terapéutico, orientado al equipo de salud que atiende a mujeres embarazadas y recién nacidos con infección por citomegalovirus (CMV) en Chile. Considera la situación epidemiológica global y latinoamericana, con recomendaciones para la evaluación clínica y de laboratorio; establece criterios de diagnóstico, propone enfoques terapéuticos de acuerdo a la situación clínica, analiza las medidas de prevención y establece una propuesta nacional para el seguimiento de esta enfermedad. Se ha puesto especial énfasis en entregar, de forma práctica, y con la mayor evidencia posible, las recomendaciones para el manejo del binomio con infección por CMV.