Utilidad diagnóstica de los tiempos de positividad de hemocultivos para distinguir verdaderas bacteriemias de contaminantes en base a un sistema automatizado / Diagnostic performance of the time to positivity of blood cultures to distinguish true bacteremia from contaminants based on an automated system

RESUMEN Objetivo. Determinar la utilidad diagnóstica de los tiempos de positividad de hemocultivos para distinguir verdaderas bacteriemias de contaminantes en el sistema automatizado «BACT/ALERT®¼. Materiales y métodos. Se realizó un estudio transversal de tipo pruebas diagnósticas, a partir de una base de datos de muestras de hemocultivos procesadas entre enero del 2016 y agosto del 2021. Se incluyeron todas las muestras de hemocultivos de pacientes con sospecha de bacteriemia, las muestras de hemocultivos fueron ingresadas al sistema «BACT/ALERT®¼ para diferenciar verdaderas bacteriemias de contaminantes. Resultados. Se analizó un total de 33 951 frascos de hemocultivos y se obtuvieron 3875 frascos positivos. El 75,2% (n=2913) del total de hemocultivos positivos fueron verdaderas bacteriemias y 24,8% (n=962) fueron contaminantes. La mediana de tiempo de positividad en los hemocultivos con verdaderas bacteriemias fue significativamente menor (16,3 horas; RIC: 11,2 - 24,9) que la mediana de tiempo de positividad de hemocultivos con contaminantes (22,5 horas; RIC: 18,4 - 31,8; p<0,001). El tiempo de positividad demostró capacidad discriminante para diferenciar verdaderas bacteriemias de contaminantes, con un AUC-ROC de 0,73 (IC95%: 0,71 - 0,75), con 85% y 63% de sensibilidad y especificidad respectivamente para el diagnóstico de contaminantes cuando el tiempo de positividad supera las 16,5 horas. La administración de antibióticos previos a la toma retrasó el tiempo de positividad, en cambio, haber presentado fiebre antes de la toma de muestra acortó el tiempo de positividad. Conclusiones. Nuestros resultados muestran un buen desempeño de los tiempos de positividad de hemocultivos para diferenciar verdaderas bacteriemias de contaminantes utilizando el sistema «BACT/ALERT®¼ cuando el tiempo de positividad fue superior a 16,5 horas.

ABSTRACT Objective. To determine the diagnostic performance of blood culture positivity times for distinguishing true bacteremia from contaminants in the automated "BACT/ALERT®" system. Materials and methods. A cross-sectional, diagnostic test-type study was conducted from a database of blood culture samples processed between January 2016 and August 2021. All blood culture samples from patients with suspected bacteremia were included; blood culture samples were entered into the "BACT/ALERT®" system to differentiate true bacteremia from contaminants. Results. We obtained 33,951 blood cultures samples, of which 3875 were positive. Of the total number of positive blood cultures, 75.2% (n=2913) were true bacteremia and 24.8% (n=962) were contaminants. The median time to positivity in blood cultures with true bacteremia was significantly shorter (16.3 hours; IQR: 11.2 - 24.9) than the median time to positivity of blood cultures with contaminants (22.5 hours; IQR: 18.4 - 31.8; p<0.001). The positivity time showed the capacity to differentiate true bacteremia from contaminants, with an AUC-ROC of 0.73 (95%CI: 0.71 - 0.75), with 85% and 63% sensitivity and specificity respectively for the diagnosis of contaminants when the positivity time exceeds 16.5 hours. The use of antibiotics prior to sampling delayed the time to positivity, while having fever before sampling shortened the time to positivity. Conclusions. Our results show good diagnostic performance of blood culture positivity times to differentiate true bacteremia from contaminants using the "BACT/ALERT®" system when the positivity time was longer than 16.5 hours.

Diagnostic performance of the time to positivity of blood cultures to distinguish true bacteremia from contaminants based on an automated system. / Utilidad diagnóstica de los tiempos de positividad de hemocultivos para distinguir verdaderas bacteriemias de contaminantes en base a un sistema automatizado.

OBJECTIVE.: To determine the diagnostic performance of blood culture positivity times for distinguishing true bacteremia from contaminants in the automated "BACT/ALERT®" system. MATERIALS AND METHODS.: A cross-sectional, diagnostic test-type study was conducted from a database of blood culture samples processed between January 2016 and August 2021. All blood culture samples from patients with suspected bacteremia were included; blood culture samples were entered into the "BACT/ALERT®" system to differentiate true bacteremia from contaminants. RESULTS.: We obtained 33,951 blood cultures samples, of which 3875 were positive. Of the total number of positive blood cultures, 75.2% (n=2913) were true bacteremia and 24.8% (n=962) were contaminants. The median time to positivity in blood cultures with true bacteremia was significantly shorter (16.3 hours; IQR: 11.2 - 24.9) than the median time to positivity of blood cultures with contaminants (22.5 hours; IQR: 18.4 - 31.8; p<0.001). The positivity time showed the capacity to differentiate true bacteremia from contaminants, with an AUC-ROC of 0.73 (95%CI: 0.71 - 0.75), with 85% and 63% sensitivity and specificity respectively for the diagnosis of contaminants when the positivity time exceeds 16.5 hours. The use of antibiotics prior to sampling delayed the time to positivity, while having fever before sampling shortened the time to positivity. CONCLUSIONS.: Our results show good diagnostic performance of blood culture positivity times to differentiate true bacteremia from contaminants using the "BACT/ALERT®" system when the positivity time was longer than 16.5 hours.

OBJETIVO.: Determinar la utilidad diagnóstica de los tiempos de positividad de hemocultivos para distinguir verdaderas bacteriemias de contaminantes en el sistema automatizado «BACT/ALERT®¼. MATERIALES Y MÉTODOS.: Se realizó un estudio transversal de tipo pruebas diagnósticas, a partir de una base de datos de muestras de hemocultivos procesadas entre enero del 2016 y agosto del 2021. Se incluyeron todas las muestras de hemocultivos de pacientes con sospecha de bacteriemia, las muestras de hemocultivos fueron ingresadas al sistema «BACT/ALERT®¼ para diferenciar verdaderas bacteriemias de contaminantes. RESULTADOS.: Se analizó un total de 33 951 frascos de hemocultivos y se obtuvieron 3875 frascos positivos. El 75,2% (n=2913) del total de hemocultivos positivos fueron verdaderas bacteriemias y 24,8% (n=962) fueron contaminantes. La mediana de tiempo de positividad en los hemocultivos con verdaderas bacteriemias fue significativamente menor (16,3 horas; RIC: 11,2 - 24,9) que la mediana de tiempo de positividad de hemocultivos con contaminantes (22,5 horas; RIC: 18,4 - 31,8; p<0,001). El tiempo de positividad demostró capacidad discriminante para diferenciar verdaderas bacteriemias de contaminantes, con un AUC-ROC de 0,73 (IC95%: 0,71 - 0,75), con 85% y 63% de sensibilidad y especificidad respectivamente para el diagnóstico de contaminantes cuando el tiempo de positividad supera las 16,5 horas. La administración de antibióticos previos a la toma retrasó el tiempo de positividad, en cambio, haber presentado fiebre antes de la toma de muestra acortó el tiempo de positividad. CONCLUSIONES.: Nuestros resultados muestran un buen desempeño de los tiempos de positividad de hemocultivos para diferenciar verdaderas bacteriemias de contaminantes utilizando el sistema «BACT/ALERT®¼ cuando el tiempo de positividad fue superior a 16,5 horas.

Evaluation of the Humoral Immune Response of a Heterologous Vaccination between BBIBP-CorV and BNT162b2 with a Temporal Separation of 7 Months, in Peruvian Healthcare Workers with and without a History of SARS-CoV-2 Infection.

Information on the effects of a heterologous booster in adult patients first vaccinated with the BBIBP-CorV vaccine is limited. This prospective cohort study evaluated the humoral response of 152 healthcare workers (HCWs) from a private laboratory in Lima (Peru) before and after receiving the BNT162b2 vaccine, with a seven-month interval since the BBIBP-CorV doses. We employed the Elecsys® anti-SARS-CoV-2 S and the cPass™ SARS-CoV-2 Neutralization Antibody (NAbs) assays to evaluate anti-S-RBD IgG and NAbs, respectively. Of the 152 HCWs, 79 (51.98%) were previously infected (PI) with SARS-CoV-2 and 73 (48.02%) were not previously infected (NPI). The proportion of HCWs with positive NAbs, seven months after the BBIBP-CorV immunization, was 49.31% in NPI and 92.40% in PI. After the booster, this ratio increased to 100% in both groups. The anti-S-RBD IgG and NAbs in the HCWs' NPI increased by 32.7 and 3.95 times more, respectively. In HCWs' PI, this increment was 5 and 1.42 times more, respectively. There was no statistical association between the history of previous SARS-CoV-2 infection and the titer of anti-S-RBD IgG and NAbs after the booster. The humoral immunity presented a robust increase after receiving the BNT162b2 booster and was more pronounced in NPI.

Factores asociados a complicaciones crónicas de diabetes mellitus tipo 2 en pacientes de un hospital general del Seguro Social de Salud del Perú / Associated factors with chronic complications of type-2-diabetes mellitus among patients from a general hospital of the Peruvian social health insurance

RESUMEN Introducción. Las complicaciones crónicas por diabetes mellitus tipo 2 (DMT2) elevan la mortalidad y carga de enfermedad en Perú, siendo necesario evaluar su prevalencia y factores asociados. Métodos. Estudio transversal, analítico, en registros de 212 pacientes adultos con DMT2 atendidos por consulta externa en un hospital general del Seguro Social del Perú, durante el año 2017. Resultados. El 71,6% de los pacientes fueron mayores de 60 años y con un tiempo de enfermedad menor de 6 años (40,5%). El 38,7% de los pacientes tuvieron alguna complicación crónica, principalmente nefropatía (48,8%) y neuropatía (45,1%). La hipertensión arterial (52,4%) y la obesidad (43,7%) fueron las comorbilidades más frecuentes en pacientes con complicaciones crónicas. Las complicaciones por DMT2 estuvieron asociadas al número de consultas médicas y monitoreo glicémico. Conclusiones. Existen factores de riesgos asociados a las complicaciones crónicas de DMT2.

ABSTRACT Introduction. The chronic complications of type-2-diabetes mellitus (T2DM) increase mortality and burden of disease in Peru, then it is necessary to evaluate its prevalence and associated factors. Methods. Cross-sectional study in records of 212 adult outpatients with T2DM attended by a social security general hospital in Peru, during 2017. Results. 71,6% of patients were older than 60 years and with a time of illness less than 6 years (40,5%). 38,7% of the patients had any chronic complication, mainly nephropathy (48,8%) and neuropathy (45,1%). Hypertension (52,4%) and obesity (43,7%) were the most frequent comorbidities in outpatients with chronic complications. Complications from DMT2 were associated with the medical consultations and glycemic monitoring. Conclusions. There are risk factors associated to chronic complications of DMT2.

Teachers' training of schoolchildren in basic life support. / Formación de escolares en soporte vital básico por sus propios profesores.

OBJECTIVES: To assess first-year secondary-school students' knowledge and performance of basic life support (BLS) 6 months after training given by their regular teachers during school hours. MATERIAL AND METHODS: Sixty-two teachers were trained in BLS instruction. They then instructed 1043 students. The students' knowledge increased significantly from mean (SD) scores of 4.42 (1.64) to 7.28 (1.85) (P < .001) and was maintained at 6 months (mean score, 5.15 [3.16]; P <.001). Performance skills were also maintained at 6 months, although the students had greater difficulty attaining ventilation targets. RESULTS: Sixty-two teachers were trained in BLS instruction. They then instructed 1043 students. The students' knowledge increased significantly from mean (SD) scores of 4.42 (1.64) to 7.28 (1.85) (P < .001) and was maintained at 6 months (mean score, 5.15 [3.16]; P < .001). Performance skills were also maintained at 6 months, although the students had greater difficulty attaining ventilation targets. CONCLUSION: Teachers' training of their own first-year secondary students during regular school hours led to changes in the students' attitudes toward the possibility of cardiac arrest and to the learning of BLS techniques.

OBJETIVO: Evaluar la formación en soporte vital básico (SVB), en horario escolar, de alumnos de primero de la enseñanza secundaria obligatoria (ESO) por sus propios profesores y su resultado a los seis meses. METODO: Estudio observacional prospectivo, con análisis pre y postintervención a los seis meses. Se impartieron cursos de SVB según las recomendaciones del European Resuscitation Council a los profesores y estos a sus alumnos. Los exámenes teóricos y prácticos fueron realizados por los profesores. RESULTADOS: . Se formaron 62 profesores que instruyeron a 1.043 alumnos. Hubo un aumento significativo de los conocimientos teóricos [de 4,42 (DE 1,64) a 7,28 (1,85), p < 0,001] aunque descendió a los seis meses [5,15 (3,16), p < 0,001]. Las habilidades prácticas también se mantuvieron a los seis meses, aunque con mayor dificultad las relacionadas con la vía aérea. CONCLUSIONES: La formación en SVB de escolares de primero de la ESO realizada por sus propios profesores en horario modificó la actitud de los escolares ante una posible parada cardiaca y logró un aprendizaje de las técnicas que desciende a los 6 meses.

Dolor abdominal agudo debido a infarto esplénico en un paciente con enfermedad heterocigota de células falciformes expuestos a la altura / Acute abdominal pain due to splenic infarct in a patient with disease heterozygote exposed silck cells to the height

La hemoglobinopatía S, depranocitosis o enfermedad de células falciformes constituye la hemoglobinopatía más frecuente en el mundo. En su forma heterocigota (Sickle Cell Trait) afecta el 8 por ciento de la población negra de los EUA y al 25 por ciento de la población negra africana, y en menor frecuencia en la zona del mediterráneo, India, Medio Oriente y América Latina. La alteración básica es la sustitución del ácido glutámico de la posición 6 de la cadena beta de Globina por Valina, la cual polimeriza a baja tensión de oxigeno; distorsionando la estructura del hematíe, aumentando la viscosidad sanguínea, bloqueando la circulación arterial capilar de diferentes áreas del organismo produciendo así microinfartos. Aunque el Infarto esplénico es raro, es reconocido como una dramática complicación de la enfermedad heterocigota de células falciformes (Sickle Cell Trait). Presentamos el caso de un paciente varón de 21 años de edad, mestizo, que cursa con un cuadro agudo de dolor abdominal posterior al arribo a la ciudad minera de Casapalca (ubicado en la Sierra del Perú; a 4200 msnm) por causas laborales y es derivado a nuestro Hospital en Lima para estudio. Presentamos el caso por ser una inusual causa de dolor abdominal agudo y por ser esta entidad poco frecuente en nuestro medio y con escasas publicaciones al respecto.

Hemoglobinopathy S, Depranocytosis or Sickle Cell Disease is the most commonhemoglobinopathy in the world. In its heterozygous form (Sickle Cell Trait), it affects 8 per cent of the black population in the U.S. and 25 per cent of the black population in Africa, and is found less frequently in the Mediterranean area, India, Middle East and Latin America. The basic alteration is a substitution of glutamic acid by valin in the sixth position of the beta globin chain, which causes polymerization at low oxygen tension thereby distorting the structure of erythrocytes and increasing blood viscosity, which,in turn, generates obstructions of the capillary arterial blood flow to different areas of the body thus causing microinfarctions. Although Splenic Infarction is rare, it is recognized as a serious complication of Heterozygous Sickle Cell Disease (Sickle Cell Trait).We present the case of a 21 year-old mestizo male patient who came in with an acute case of abdominal pain after arriving to work in the Casapalca mining city (located in the Peruvian Andes at 4200 m.a.s.l.) and was referred to our Hospital in Lima for exams. We present the case because it is an unusual cause of acute abdominal pain, and because this condition is rare in Peru and there are few publications about it.

[Acute abdominal pain due to splenic infarction in a patient with heterozygous sickle cell disease exposed to high altitude]. / Dolor abdominal agudo debido a infarto esplénico en un paciente con enfermedad heterocigota de células falciformes expuesto a la altura.

Hemoglobinopathy S, Depranocytosis or Sickle Cell Disease is the most common hemoglobinopathy in the world. In its heterozygous form (Sickle Cell Trait), it affects 8% of the black population in the U.S. and 25% of the black population in Africa, and is found less frequently in the Mediterranean area, India, Middle East and Latin America. The basic alteration is a substitution of glutamic acid by valin in the sixth position of the beta globin chain, which causes polymerization at low oxygen tension thereby distorting the structure of erythrocytes and increasing blood viscosity, which, in turn, generates obstructions of the capillary arterial blood flow to different areas of the body thus causing microinfarctions. Although Splenic Infarction is rare, it is recognized as a serious complication of Heterozygous Sickle Cell Disease (Sickle Cell Trait). We present the case of a 21 year-old mestizo male patient who came in with an acute case of abdominal pain after arriving to work in the Casapalca mining city (located in the Peruvian Andes at 4200 m.a.s.l.) and was referred to our Hospital in Lima for exams. We present the case because it is an unusual cause of acute abdominal pain, and because this condition is rare in Peru and there are few publications about it.