Initial assessment of “Gissell's stain”: A novel histopathological method for the identification of Helicobacter pylori / Valoración inicial de la tinción de Gissell, un nuevo método histopatológico en la identificación del Helicobacter pylori

Introduction and Objectives: The histopathological identification of Helicobacter pylori using the routine method (haematoxylin–eosin) is not only very difficult but also has low sensitivity. Giemsa staining is often used in addition, but different protocols do not produce homogeneous results. Furthermore, the Gold Standard recommended by the European Helicobacter Pylori Study Group has been applied in very few studies, thus resulting in uncertain outcomes. Therefore, a new staining method is required to overcome these limitations. The aim of this study was to evaluate the diagnostic capacity and inter-observer agreement of “Gissell's stain”. Material and Methods: A cross-sectional study evaluated 99 gastric paraffin blocks from a private laboratory. Three sections were prepared from each block, and haematoxylin–eosin (HE), Giemsa and “Gissell's stain” methods were applied. The kappa statistics, sensitivity, specificity, and predictive values were calculated. Results: “Gissell's stain” obtained the highest inter-observer agreement (kappa=0.87) compared to the other two methods (HE, kappa=0.51; Giemsa, kappa=0.83). It also obtained the best sensitivity and negative predictive value (97.1% and 98.3%, respectively) compared with the other two methods (HE: 68.6% and 85.1%, respectively; Giemsa: 88.6% and 93.9%, respectively). Conclusions: Given its unique characteristics (fast, cheap, accessible, and easy to use), in addition to its statistical reliability, “Gissell's stain” has great potential for routine use in the identification of H. pylori.(AU)

Introducción y objetivos: La identificación histopatológica del Helicobacter pylori, utilizando hematoxilina-eosina (HE) como método de rutina es frecuentemente dificultosa y con una baja sensibilidad. El método de Giemsa es usado a veces de modo adicional, pero diferentes protocolos no producen resultados homogéneos. Además, el método recomendado por el grupo europeo de estudio de Helicobacter pylori ha sido empleado en pocos estudios, resultando en datos discrepantes. Por tanto, un método alternativo eficaz podría superar estas limitaciones. El presente estudio valora la agudeza diagnostica y el acuerdo interobservador en la aplicación del método de Gissell. Material y métodos: Un estudio interobservador de 99 biopsias gástricas provenientes de la practica privada. De cada caso se prepararon tres muestras teñidas correspondientemente con: HE, Giemsa y Gissell. Se procedió mediante estadística kappa a valorar la sensibilidad, especificidad y valores predictivos. Resultados: La técnica de Gissell obtuvo el mayor acuerdo interobservador con un kappa con 0,87, comparado con la HE (kappa = 0,51) y Giemsa (kappa = 0,83). Además, obtuvo la mayor sensibilidad y valor predictivo negativo comparado con los otros dos métodos. Conclusiones: Dadas sus características prácticas, tales como rapidez, economía, accesibilidad y facilidad de uso, además de su fiabilidad estadística, el método de Gissell posee un gran potencial para la identificación rutinaria del Helicobacter pylori.(AU)

Initial assessment of "Gissell's stain": A novel histopathological method for the identification of Helicobacter pylori.

INTRODUCTION AND OBJECTIVES: The histopathological identification of Helicobacter pylori using the routine method (haematoxylin-eosin) is not only very difficult but also has low sensitivity. Giemsa staining is often used in addition, but different protocols do not produce homogeneous results. Furthermore, the Gold Standard recommended by the European Helicobacter Pylori Study Group has been applied in very few studies, thus resulting in uncertain outcomes. Therefore, a new staining method is required to overcome these limitations. The aim of this study was to evaluate the diagnostic capacity and inter-observer agreement of "Gissell's stain". MATERIAL AND METHODS: A cross-sectional study evaluated 99 gastric paraffin blocks from a private laboratory. Three sections were prepared from each block, and haematoxylin-eosin (HE), Giemsa and "Gissell's stain" methods were applied. The kappa statistics, sensitivity, specificity, and predictive values were calculated. RESULTS: "Gissell's stain" obtained the highest inter-observer agreement (kappa=0.87) compared to the other two methods (HE, kappa=0.51; Giemsa, kappa=0.83). It also obtained the best sensitivity and negative predictive value (97.1% and 98.3%, respectively) compared with the other two methods (HE: 68.6% and 85.1%, respectively; Giemsa: 88.6% and 93.9%, respectively). CONCLUSIONS: Given its unique characteristics (fast, cheap, accessible, and easy to use), in addition to its statistical reliability, "Gissell's stain" has great potential for routine use in the identification of H. pylori.

Gestational complications associated with SARS-CoV-2 infection in pregnant women during 2020-2021: systematic review of longitudinal studies.

OBJECTIVES: To identify gestational complications associated with SARS-CoV-2 infection in pregnant women during 2020-2021. CONTENT: The risk of gestational complications was confirmed during SARS-CoV and MERS-CoV infection. However, this is not robust for COVID-19 because there is still no scientific evidence from longitudinal studies. A systematic review was performed using four databases, and 14 prospective or retrospective cohorts were finally included in the analysis. SUMMARY: The most frequently associated sociodemographic characteristic or comorbidity was the presence of any previous comorbidity (9 studies, 64.3%), followed by ethnicity and age (6 studies each one, 42.9%). The most frequently associated gestational complications in mothers were the admission to Intensive Care Unit (4 studies, 28.6%) and gestational age at delivery <37 weeks (3 studies, 21.4%). The most frequently associated gestational complications in newborns were preterm birth (4 studies, 28.6%) and the admission to Neonatal Intensive Care Unit (2 studies, 14.3%). OUTLOOK: Pregnant women infected with SARS-CoV-2 appear to have a higher risk of admission to Intensive Care Unit. Newborns of mothers infected with SARS-CoV-2 appear to have a higher risk of preterm birth and admission to Neonatal Intensive Care Unit.

Validation of a new method for estimating low platelet counts: G&S method / Validação de um novo método para estimação de contagens plaquetárias baixas: método G&S

ABSTRACT Introduction: Automated hematology analyzers are able to produce low platelet counts with great precision and accuracy. However, these analyzers may produce erroneous counts due to the presence of interferences. Therefore, additional methodologies are required to confirm platelet counts, such as blood smear and a direct count, using the Neubauer chamber. Objective: To validate the reliability estimate produced by the G&S method. Material and method: One hundred and fifty platelet counts were analyzed in the hematology and emergency laboratories of the Hospital Nacional Docente Madre-Niño San Bartolomé, in Lima, Peru, by four methodologies: one optical platelet count (PLTO), one indirect blood smear count (Indirect), and two direct counts (Direct and G&S). Descriptive and inferential statistics were used to compare the groups. Results: A significant difference was observed in the distribution of the four methodologies and, after applying the post-hoc analysis, a similarity between the PLTO and G&S methods was found. Also, the Direct, G&S and Indirect methods showed a positive correlation with the PLTO method. The Bland-Altman test demonstrated that the G&S method presented a high agreement with the PLTO method. Conclusion: The G&S method is inexpensive, easy to perform, and has demonstrated statistical reliability concerning the automated methodology, and is useful for confirming low platelet counts after a suspected error by the automated equipment or when this device is not available for use.

RESUMEN Introducción: Los analizadores automáticos hematológicos son capaces de realizar bajos recuentos de plaquetas con precisión y exactitud. Sin embargo, eses analizadores pueden producir recuentos erróneos debido a la presencia de interferencias. Así, métodos adicionales son necesarios para confirmar los recuentos de plaquetas, como el frotis de sangre y un recuento directo en cámara de Neubauer. Objetivo: Validar la confiabilidad de la estimación del método G&S. Material y método: Se analizaron ciento cincuenta recuentos de plaquetas en los laboratorios de hematología y emergencias del Hospital Nacional Docente Madre-Niño San Bartolomé, en Lima, Perú, por cuatro métodos: un recuento óptico de plaquetas (PLTO), un recuento indirecto por frotis de sangre (Indirecto) y dos recuentos directos (Directo y G&S). Se utilizaron estadísticas descriptivas e inferenciales para comparar los grupos. Resultados: Se observó diferencia significativa en la distribución de los cuatro métodos y, luego de la aplicación del análisis post-hoc, se encontró similitud entre los métodos PLTO y G&S. Además, los métodos Directo, G&S e Indirecto mostraron correlación positiva con el método PLTO. La prueba de Bland-Altman demostró que el método G&S presentó alta concordancia con el método PLTO. Conclusión: El método G&S es económico, fácil de llevar a cabo y demostró confiabilidad estadística en relación con el método automatizado, siendo útil para confirmar bajos recuentos de plaquetas después de una sospecha de error por el equipo automático o cuando el laboratorio no cuente con éste.

RESUMO Introdução: Os analisadores automatizados hematológicos são capazes de realizar baixas contagens de plaquetas com precisão e exatidão. No entanto, esses analisadores podem produzir contagens erradas devido à presença de interferências. Dessa forma, métodos adicionais são necessários para confirmar as contagens de plaquetas, como esfregaço de sangue e uma contagem direta, utilizando a câmara de Neubauer. Objetivo: Validar a confiabilidade gerada pela estimativa do método G&S. Material e método: Cento e cinquenta contagens de plaquetas foram analisadas nos laboratórios de hematologia e emergência do Hospital Nacional Docente Madre-Niño San Bartolomé em Lima, Peru, por quatro metodologias: uma contagem óptica de plaquetas (PLTO), uma contagem indireta por esfregaço de sangue (Indireto) e duas contagens diretas (Direto e G&S). Estatísticas descritivas e inferenciais foram utilizadas para comparar os grupos. Resultados: Observou-se diferença significativa na distribuição das quatro metodologias e, após a aplicação da análise post-hoc, obteve-se semelhança entre os métodos PLTO e G&S. Além disso, os métodos Direto, G&S e Indireto mostraram correlação positiva com o método PLTO. O teste de Bland-Altman demonstrou que o método G&S apresentou alta concordância com o método PLTO. Conclusão: O método G&S é barato, fácil de executar e demonstrou confiabilidade estatística em relação à metodologia automatizada, sendo útil para confirmar baixas contagens de plaquetas após uma suspeita de erro pelo equipamento automatizado ou quando não se tem esse aparelho disponível para uso.