A comparative systematic review and meta-analysis on the diagnostic accuracy of non-invasive tests for Helicobacter pylori detection in elderly patients.

Background: Helicobacter pylori (H. pylori) infection, a type I carcinogen, affects approximately 50% of the global population, correlating with various gastric pathologies. Notably, diagnostic sensitivities of non-invasive methods, such as the stool antigen test (HpSA), Serology, and Urea Breath Test (UBT), have been suggested to be less effective in older age groups. This study systematically reviews and meta-analyzes the diagnostic accuracy of these tests within the elderly population. Methods: A comprehensive literature search was performed across multiple databases, including PubMed, Medline, and Web of Science, up to July 2023. Data were pooled and analyzed using random-effects models. Sensitivity, specificity, and Diagnostic Odds Ratios (DOR) were computed for the tests. Heterogeneity and risk of bias were assessed. Results: Eight studies involving diverse geographic locations and totaling between 46 and 1,441 participants per study were included. The pooled sensitivity and specificity for HpSA were 72.5 and 94.7%, for Serology 83.7 and 73.3%, and for UBT 96.4 and 88.3%, respectively. DOR for UBT, HpSA, and Serology were 94.5, 47.9, and 14.2, respectively. High levels of heterogeneity were observed across the studies. Conclusion: UBT and HpSA proved effective for diagnosing H. pylori in those over 60, while serology showed lower specificity. Despite methodological variations in available studies, these non-invasive tests offer reliable alternatives, especially for older patients who recently undergone endoscopy or without an indication for it, warranting consideration by healthcare practitioners.

Proteomics Profiling of Stool Samples from Preterm Neonates with SWATH/DIA Mass Spectrometry for Predicting Necrotizing Enterocolitis.

Necrotizing enterocolitis (NEC) is a life-threatening condition for premature infants in neonatal intensive care units. Finding indicators that can predict NEC development before symptoms appear would provide more time to apply targeted interventions. In this study, stools from 132 very-low-birth-weight (VLBW) infants were collected daily in the context of a multi-center prospective study aimed at investigating the potential of fecal biomarkers for NEC prediction using proteomics technology. Eight of the VLBW infants received a stage-3 NEC diagnosis. Stools collected from the NEC infants up to 10 days before their diagnosis were available for seven of them. Their samples were matched with those from seven pairs of non-NEC controls. The samples were processed for liquid chromatography-tandem mass spectrometry analysis using SWATH/DIA acquisition and cross-compatible proteomic software to perform label-free quantification. ROC curve and principal component analyses were used to explore discriminating information and to evaluate candidate protein markers. A series of 36 proteins showed the most efficient capacity with a signature that predicted all seven NEC infants at least a week in advance. Overall, our study demonstrates that multiplexed proteomic signature detection constitutes a promising approach for the early detection of NEC development in premature infants.

Selective Visualization of Live Intestinal Parasites in Stool Specimens Without Purification.

PURPOSE: Microscopic observation of live parasites in the stool is an important diagnostic tool in human and veterinary medicine. Because of the presence of large amounts of contaminating organic matter, microscopic analysis must be preceded by time-consuming pre-purification steps. Transmission-through-dye (TTD) optical microscopy obviates this problem. The purpose of this study is to illustrate the use of TTD for the analysis of stool samples. METHODS: TTD imaging is based on the exclusion of a strongly absorbing dye by living cells. A food colorant Acid Blue 9 (AB9) is added to a fecal suspension, and the sample is observed under transmitted illumination through a 630 nm bandpass filter. AB9 strongly absorbs red light, and it comes out of the sample significantly attenuated. However, if a viable cell of any origin is present in the sample, it excludes the dye and reduces the depth of the light-absorbing layer. RESULTS: Live cells or eggs appear bright red on a dark background, while most of the organic contaminants remain dark. The method has been demonstrated on schistosomes, hookworms, giardia, yeast, and other organisms. CONCLUSION: TTD dramatically increases the visibility of live parasites and permits their direct observation in a fecal suspension. TTD can be enabled on any microscope by simply adding a red filter.

EuNPs-mAb fluorescent probe based immunochromatographic strip for rapid and sensitive detection of porcine epidemic diarrhea virus.

Porcine epidemic diarrhea (PED), induced by porcine epidemic diarrhea virus (PEDV) causes acute diarrhea, vomiting, dehydration and high mortality in neonatal piglets, resulting in significant economic losses in the pig industries. In this study, an immunochromatographic assay (ICA) based on a EuNPs-mAb fluorescent probe was developed and optimized for rapid detection of PEDV. The limit of detection (LOD) of the ICA was 0.218 µg/mL (2.725 × 103 TCID50/mL) and its linear detection range was 0.03125-8 µg/mL (3.91 × 102-105 TCID50/mL). The ICA was also validated for the detection of PEDV in swine stool samples. 60 swine stool samples from southern China were analyzed by the ICA and RT-PCR, and the results showed that the coincidence rate of the ICA to RT-PCR was 86.67%, which was significantly higher than that of AuNPs based ICA. The ICA is sensitive and specific and can achieve on-site rapid detection of swine stool samples. Therefore, the ICA has a great potential for PED diagnosis and prevention.

A new immunochromatographic assay for on-site detection of porcine epidemic diarrhea virus based on monoclonal antibodies prepared by using cell surface fluorescence immunosorbent assay.

BACKGROUND: Porcine epidemic diarrhea virus (PEDV) is a highly effective pathogen that can cause death of new-born piglet, resulting in big economical loss in pig farming industry. For rapid detection of PEDV, a new immunochromatographic assay (ICA) based on monoclonal antibodies (mAbs) was developed in this study. RESULTS: The mAbs were prepared by using PEDV positive hybridoma cells that were selected by using cell surface fluorescence immunosorbent assay (CSFIA). Fourteen mAbs against PEDV strain isolated from south of China were prepared. The optimal mAb 4A11 was coated on NC membrane as the capturing reagent and the mAb A11H7 was coupled to gold nanoparticles (AuNPs) as detection reagent for the new ICA. The new ICA was used to measure PEDV in phosphate buffer containing tween-20. Results indicated that the limit of detection (LOD) of the new ICA was 0.47 µg/mL (5.9 × 103 TCID50/mL) and the liner detection range of the ICA was 0.625-10 µg/mL (7.8 × 103-105 TCID50/mL). The specificity analysis results showed that this new ICA had no cross reaction in the presence of other porcine viruses. The ICA was also validated for the detection of PEDV in swine stool samples with little interference from swine stool. To compare its accuracy to other traditional detection methods, 27 swine stool samples from south of China were investigated with the new developed ICA, commercial strip and RT-PCR. Results showed that the new ICA was more comparable to RT-PCR than commercial test strip. CONCLUSIONS: A new ICA based on mAbs prepared by CSFIA was developed in this study. It was a sensitive, specific and rapid method that could be used for on-site detection of PEDV and therefore was useful for the diagnosis and prevention of PED.

German guideline for the management of adverse reactions to ingested histamine: Guideline of the German Society for Allergology and Clinical Immunology (DGAKI), the German Society for Pediatric Allergology and Environmental Medicine (GPA), the German Association of Allergologists (AeDA), and the Swiss Society for Allergology and Immunology (SGAI).

Adverse food reactions are far more often perceived than objectively verified. In our scientific knowledge on non-allergic adverse reactions including the so called histamine intolerance, there are large deficits. Due to the fact that this disorder is increasingly discussed in the media and the internet, more and more people suspect it to be the trigger of their symptoms. The scientific evidence to support the postulated link between ingestion of histamine and adverse reactions is limited, and a reliable laboratory test for objective diagnosis is lacking. This position paper by the "Food Allergy" Working Group of the German Society for Allergology and Clinical Immunology (DGAKI) in collaboration with the German Association of Allergologists (AeDA), the Society for Pediatric Allergology and Environmental Medicine (GPA), and the Swiss Society for Allergology and Immunology (SGAI) reviews the data on the clinical picture of adverse reactions to ingested histamine, summarizes important aspects and their consequences, and proposes a practical diagnostic and therapeutic approach.

Análisis de costo - oportunidad del uso de coproscópico en diarrea aguda en menores de 5 años / Cost-opportunity analysis of the use of fecal screening test in acute diarrhea in children under 5 years old / Análise custo-oportunidade do uso do teste de verificação fecal na diarreia aguda em crianças menores de 5 anos

Objetivo: Analizar el uso de coproscópico de rutina, en menores de 5 años con diarrea aguda, en un Hospital de primer nivel de Bogotá y evaluar la mejor forma de asignar los recursos usados en esta intervención a una alternativa que produzca mayor beneficio. Métodos: Revisión de la literatura en diarrea aguda y utilidad del coproscópico. Recopilación de datos de consultas por diarrea en niños de 0-5 años y coproscópicos realizados entre octubre de 2011 y febrero de 2012 en Hospital de Bogotá, con selección de aquellos sugestivos de enfermedad enteroinvasiva, cálculo del costo de su uso y estimación del costo-oportunidad en realización de programas que reduzcan la morbimortalidad en menores de 5 años. Resultados: La principal etiología de la enfermedad diarreica es viral. Más de 5 leucos/campo tiene una sensibilidad y especificidad adecuada que no supera la valoración clínica. Se solicitó coproscópico en 44.8%; el 14.6% sugerían enfermedad enteroinvasiva. El 30.2% de los pacientes no requerían coproscópico y su costo corresponde a $5.266.400. Conclusiones: La utilidad del coproscópico es baja y no mejora la probabilidad pretest de diarrea enteroinvasiva, es necesario abordar la el análisis de costo-oportunidad para la distribución correcta de los recursos en intervenciones que reduzcan la morbimortalidad.

Objective: To analyze the use of routine fecal screening test in children under 5 years old, with acute diarrheal disease in a primary care level hospital in Bogotá and evaluate how best the resources used in this intervention can be allocated to an alternative one, that produces greater benefit . Methods: Review of the literature on acute diarrhea and utility of fecal screening test. Data collection of diarrhea consultations in children under 5 years old and fecal screening test done between October 2011 and February 2012 in a Bogota´s Hospital. Selecting those one, which diagnoses enteroinvasive diarrhea and costing of routine use, and estimated opportunity-cost in programs to reduce morbi-mortality in children under 5 years old. Results: The main etiology of diarrhea is viral. More than 5 WBCs / field has adequate sensitivity and specificity, but the clinical assessment is better on detection of enteroinvasive disease. Fecal screening test was requested in 44.8 %; 14.6 % was suggested enteroinvasive disease. The resources used in 30.2 % of patients did not require the test match to US$2.633. Conclusions: The utility of Fecal screening test is low and does not imprve the pretest probability of enteroinvasive diarrhea. Is necessary to address the cost-opportunity analysis for the proper distribution of resources in intervetions that reduce the morbi-mortality.

Objetivo: Analisar o uso do teste rotineiro de triagem fecal em crianças menores de 5 anos com doença diarréica aguda em um hospital de atenção primária em Bogotá e avaliar a melhor forma de alocação dos recursos utilizados nessa intervenção para uma alternativa que produza maior benefício. Métodos: Revisão da literatura sobre diarréia aguda e utilidade do teste de triagem fecal. Coleta de dados de consultas de diarréia em crianças menores de 5 anos e teste de triagem fecal realizado entre outubro de 2011 e fevereiro de 2012 em um hospital de Bogotá. Selecionar aquelas que diagnosticam diarréia entero-invasiva e custo de uso rotineiro e custo de oportunidade estimado em programas para reduzir a morbi-mortalidade em crianças menores de 5 anos. Resultados: A principal etiologia da diarréia é viral. Mais de 5 WBCs / campo tem sensibilidade e especificidade adequadas, mas a avaliação clínica é melhor na detecção de doença enteroinvasiva. O teste de triagem fecal foi solicitado em 44,8%; 14,6% foi sugerida doença enteroinvasiva. Os recursos utilizados em 30,2% dos pacientes não necessitaram do teste correspondente a US $ 2,633. Conclusões: A utilidade do teste de triagem Fecal é baixa e não melhora a probabilidade pré-teste de diarréia enteroinvasiva. É necessário abordar a análise custo-oportunidade para a distribuição adequada de recursos em intervenções que reduzam a morbi-mortalidade.

[Diagnosis of the porphyrias : From A (as in aminolevulinic acid) to Z (as in zinc protoporphyrin)]. / Diagnostik der Porphyrien : Von A (wie Aminolävulinsäure) bis Z (wie Zink-Protoporphyrin).

The porphyrias comprise a clinically, biochemically, and genetically heterogeneous group of predominantly hereditary metabolic disorders resulting from a dysfunction along the heme biosynthetic pathway. Whereas most variants can manifest with different cutaneous symptoms, some types only reveal life-threatening acute neurovisceral attacks. Therefore, interdisciplinary care of these patients is advisable. In this article, we provide an overview of characteristic clinical and laboratory findings in the various forms of porphyria and a diagnostic algorithm.

Prevalence of cryptosporidiosis in renal transplant recipients presenting with acute diarrhea at a single center in Pakistan.

BACKGROUND: Cryptosporidium is an intracellular protozoan organism which causes diarrhea, both in immunocompetent and immunocompromised hosts. Renal transplant recipients are prone to develop a variety of infections including protozoal infections. OBJECTIVES: The aim of this study was to determine the prevalence of cryptosporidiosis in our renal transplant recipients presenting with acute diarrhea. PATIENTS AND METHODS: During six months of the study, 644 renal transplant recipients presented with acute diarrhea. Single stool sample was obtained for detailed analysis including gross and microscopic examination for red blood cells, pus cells, ova, cysts, and protozoa. The modified Ziehl-Neelsen (ZN) staining was done to identify the oocysts of cryptosporidia. RESULTS: Out of 644 renal transplant patients, oocysts of cryptosporidia were identified in 343 patients (53%). Detailed stool analysis of these patients showed the presence of numerous pus cells in 27 (7.9%) patients, co-infection with giardia intestinalis cysts in 15 (4.3%), and entamoeba histolytica cysts in 10 (2.9%). In all, out of 343 patients, 43 (12.5%) had dual infection with bacteria and protozoa in addition to cryptosporidiosis. CONCLUSIONS: Cryptosporidium is an important pathogen causing acute diarrhea in renal transplant recipients in our set up. Stool examination is usually negative for pus cells. It is recommended that in all transplant recipients presenting with acute diarrhea modified ZN staining should be done to rule out cryptosporidiosis in highly endemic areas like Pakistan.

Prevalencia de norovirus en muestras de heces procedenes del laboratotio del Hospital José Gregorio Hernández / The prebalence of the norovirus in fecal samples which originated at the laboratory of the Hospital José Gregorio Hernandez. Catia, Caracas

La gastroenteritis en Venezuela es la principal causa de muerte y morbilidad en la población infantil. La falta de adecuadas metodologías diagnósticas en el laboratorio de rutina impide identificar todos los posibles microorganismos causantes de gastroenteritis enfocando el diagnóstico al estudio de parásitos protozoarios o helmintos, bacterias aeróbicas y en menos grado virus y hongos. Basado en esto, decidimos determinar si el norovirus es el agente causal de gastroenteritis en nuestro país, determinar las condiciones ambientales y sanitarias en la comunidad en estudio y analizar los esquemas y técnicas diagnósticas actualmente utilizadas en los centros de salud. Se evaluaron 173 muestras de heces de pacientes que asistieron al laboratorio del Hospital Magallanes de Catia. Se utilizó un kit de inmunoensayo enzimático, ELISA RIDASCREEN norovirus de r-biopharm AG, alemania, el cual permite el diagnóstico in vitro e identificación cualitativa de los norovirus genogrupo I y II en muestras de heces. De las 173 muestras de heces analizadas 29 (16,76%) resultaron positivas, 144 (83,32%) fueron negativas. Cuando se evaluaron por grupo etario, el grupo de niños de 6-13 años se obtuvo el mayor número de muestras positivas (8) seguido del grupo de niños 0 - 5 años con 7 muestras positivas. Se encontró mayor frecuencia de norovirus en muestras con aspecto heterogéneo, color marrón y verde de consistencia blanda y alcalina, así mismo 19,08% de las muestras fueron positivas para algún parásito (Protozoario o Helmintos) visibles en el examen microscópico directo. Se demostró que 16,76% de las diarreas en le grupo evaluado fueron por norovirus, siendo importante su determinación para el diagnóstico de gastroenteritis.

Gastroenteritis is the main cause of death and morbidity among children in Venezuela. The lack of adequate diagnostic methodologies in the laboratory reduce the identification of all possible microorganisms that cause gastroenteritis, since they focus the diagnosis on the study of parasites, protozoa or helminthes, aerobic bacteria and, to a lesser degree, on viruses and fungi. Based on this, we decided to determine if the norovirus is the causal agent of gastroenteritis in our country; to determine the environmental and sanitary conditions in the community under study; and, to analyze the diagnostic framework and techniques currently used in healthcare centers. 173 fecal samples of patients that visited the laboratory of the Hospital Magallanes in Catia were evaluated. An enzymatic immunoassay kit, ELISA RIDASCREEN norovirus of r-biopharm AG, Germany, was used since it permits the in vitro diagnosis and the qualitative identification of the norovirus genogroups I and II in fecal samples. Of the 173 stool samples analyzed, 29 (16.76%) tested positive, 144 (83.32%) tested negative. When evaluated by age group, the group of children between 6-13 years old presented the greatest number of positive samples (8), followed by the group of children between 0-5 with 7 positive samples. The highest frequency of norovirus was found in samples of heterogeneous appearance, brown-green color, soft and alkaline consistency; also, 19.08% of the samples tested positive for some type of parasite (Protozoa or Helminthes), visible with direct microscopic examination. So, we can conclude that it was shown that 16.76% of the diarrheas in the evaluation group were due to norovirus, its determination being important for the diagnosis of gastroenteritis.

A spectrum of pathogenic and non-pathogenic intestinal parasites in pre-employment medical check-up for workers and their families.

INTRODUCTION: Stool analysis plays an important role in pre-employment tests for the screening of intestinal parasites in new workers. OBJECTIVE: to explore the spectrum of intestinal parasites in stool samples of workers and their families during the pre-employment tests over a one-year period at King Abdulaziz University Hospital (KAUH). METHODS: Subjects were selected sequentially from routine single stool analysis forms labeled for pre-employment tests. Stool specimens were examined using the formalin ether technique at the parasitology laboratory at KAUH. RESULTS: Two hundred and ninety two different stool samples of the workers and their families were studied. Their ages ranged from 3 to 72 year old (mean 32 ± 8.5 SD) and females formed 58.6% of the number. Intestinal parasites were detected in 161 workers (55%). The prevalence of intestinal parasites in Saudi workers was significantly lower than non-Saudi nationals, 15.8% versus 57.9% (p<0.001). Of all the positive cases, pathogenic intestinal parasites were found in 40 % of them and the commonest were Trichuris trichuria (39.1%), Hookworm (34.2%), Entamoeba histolytica (16.1%). Non-pathogenic parasites were found in 19.5% and the commonest were Blastocystis hominis (34.8%), Endolimax nana (29.8%), Entamoeba coli (15.5%). One type of parasite was found in 75 (46.6%) and multiple different parasites were found in 86 (53.4%). There was a high significant correlation between the detection of pathogenic and non-pathogenic parasites (p<0.001). CONCLUSION: Infestation of stools with pathogenic and non-pathogenic intestinal parasites is a common finding in more than half of the new workers and their families. The correlation between non-pathogenic and pathogenic parasites reflects mutual risk factors, and their potential hazards cannot be overlooked. Effective stool screening and eradication strategies for intestinal parasites in new workers should be rigorously enforced.