Infectious etiology and indicators of malabsorption or intestinal injury in childhood diarrhea. / Etiología infecciosa e indicadores de malabsorción o daño intestinal en diarrea infantil

INTRODUCTION: The multifactorial etiology of gastroenteritis emphasizes the need for different laboratory methods to identify or exclude infectious agents and evaluate the severity of diarrheal disease. OBJECTIVE: To diagnose the infectious etiology in diarrheic children and to evaluate some fecal markers associated with intestinal integrity. MATERIALS AND METHODS: The study group comprised 45 children with diarrheal disease, tested for enteropathogens and malabsorption markers, and 76 children whose feces were used for fat evaluation by the traditional and acid steatocrit tests. RESULTS: We observed acute diarrhea in 80% of the children and persistent diarrhea in 20%. Of the diarrheic individuals analyzed, 40% were positive for enteropathogens, with rotavirus (13.3%) and Giardia duodenalis (11.1%) the most frequently diagnosed. Among the infected patients, occult blood was more evident in those carrying pathogenic bacteria (40%) and enteroviruses (40%), while steatorrhea was observed in infections by the protozoa G. duodenalis (35.7%). Children with diarrhea excreted significantly more lipids in feces than non-diarrheic children, as determined by the traditional (p<0.0003) and acid steatocrit (p<0.0001) methods. Moreover, the acid steatocrit method detected 16.7% more fecal fat than the traditional method. CONCLUSIONS: Childhood diarrhea can lead to increasingly severe nutrient deficiencies. Steatorrhea is the hallmark of malabsorption, and a stool test, such as the acid steatocrit, can be routinely used as a laboratory tool for the semi-quantitative evaluation of fat malabsorption in diarrheic children.

Introducción. La etiología multifactorial de la gastroenteritis enfatiza la necesidad de usar diferentes métodos de laboratorio para identificar o excluir agentes infecciosos y evaluar la gravedad de la enfermedad diarreica. Objetivo. Diagnosticar la etiología infecciosa de la diarrea en niños y evaluar algunos marcadores fecales asociados con la integridad intestinal. Materiales y métodos. Se estudiaron 45 niños con enfermedad diarreica, en los cuales se evaluaron la presencia de enteropatógenos y los marcadores de malabsorción. Se analizaron las muestras fecales de 76 niños, mediante las pruebas de esteatocrito tradicional y esteatocrito ácido, para la cuantificación de la grasa. Resultados. Se observó diarrea aguda en el 80 % de los niños y diarrea persistente en el 20 %. De los individuos con diarrea, el 40 % fue positivo para enteropatógenos; los más diagnosticados fueron rotavirus (13,3 %) y Giardia duodenalis (11,1 %). Entre los pacientes infectados, la sangre oculta fue más evidente en aquellos portadores de bacterias patógenas (40 %) o enterovirus (40%), mientras que la esteatorrea se observó en infecciones por el protozoo G. duodenalis (35,7 %). Los niños con diarrea excretaron significativamente más lípidos en las heces que aquellos sin diarrea, según lo determinado por los métodos de esteatocrito tradicional (p<0,0003) y esteatocrito ácido (p<0,0001). Conclusiones. La diarrea infantil puede provocar deficiencias graves de nutrientes. La esteatorrea es distintiva de la malabsorción intestinal y puede detectarse mediante la estimación del esteatocrito ácido. Esta prueba podría utilizarse de forma rutinaria como una herramienta de laboratorio para la evaluación semicuantitativa de la malabsorción de grasas en niños con diarrea.

Detection of IgG Anti-Giardia duodenalis Antibodies in Sera by Indirect Immunofluorescence and Western Blotting Assays.

INTRODUCTION: Serological assays are alternative laboratory tools for the diagnosis of parasitic infections. The aim of this work was to evaluate the performance of the indirect fluorescent antibody test (IFAT) and Western blotting (WB) for the detection of IgG anti-Giardia antibodies in human sera. METHODOLOGY: Sera from individuals infected with Giardia duodenalis, other parasites or non-parasitized were selected for serological assays. Ninety-seven sera were tested by IFAT at 1:20 and 1:40 dilutions and of these, 40 samples were also analyzed by WB. RESULTS: The sensitivity and specificity of the IFAT was 97% and 46.9% at 1:20 sera dilution, and 39.4% and 59.4% at 1:40 sera dilution. The low molecular weight polypeptides fractions of 25 kDa, 27-31 kDa and 45-55 kDa were the most frequently identified by the sera of individuals infected with G. duodenalis, along with low cross-reactivity, presenting an individual sensitivity of 42.8%, 50.0% and 57.1%, and specificity of 83.3%, 83.3% and 91.7%, respectively. The highest overall sensitivity of WB (85.7%) was based on the immunoreactivity of sera with at least one of those proteins. The concordance between the detection of G. duodenalis in feces by microscopy and the WB results was considered substantial (Kappa = 0.61). CONCLUSION: Constant exposure to Giardia infection throughout a lifetime can maintain high levels of specific antibodies in serum, even without active infection. Moreover, proteins found in intestinal amoebas may hinder the serological diagnosis of giardiasis in endemic areas due to cross-reactivity, which can be partially solved using Giardia low molecular weight proteins.

Anthelmintic treatment follow up in a rural community in Camamu, Bahia, Brazil.

Enteroparasites are an important public health problem and the treatment seeks to cure and reduce transmission. The aim of this study was to evaluate the therapeutic efficacy of anthelmintic treatment in individuals living in a rural community area in Camamu, Bahia, Brazil. The parasitological diagnosis was performed by spontaneous sedimentation, Baermann-Moraes and Agar Plate Culture methods. A total of 212 individuals were evaluated. The most frequent helminth was Trichuris trichiura, 24.5% (52/212), followed by Ascaris lumbricoides, 21.2% (45/212), hookworms, 16.5% (35/212), and S. stercoralis, 4.7% (10/212). In the anthelmintic treatment follow up, T. trichiura infection presented the lowest parasitological cure rate, only 60.6% (20/33). Hookworm, Ascaris lumbricoides and Strongyloides stercoralis infections demonstrated cure rates of 70.5 (12/17), 78.1 (25/32) and 100% (5/5), respectively. Individuals who remained infected underwent a new drug therapy. The second parasitological cure rate for T. trichiura was 38.5% (5/13), and 66.7% (2/3) and 75% (3/4) for hookworms and Ascaris lumbricoides, respectively. Trichuris trichiura infection presented the lowest parasitological cure rate at this second evaluation. This reinforces the need to perform a follow-up of all treated individuals. The possibility of drug resistance denotes the necessity for studies to clarify the mechanisms and to evaluate new therapeutic approaches.

Seroepidemiological Survey of Chronic Chagas Disease in a Rural Community in Southern Bahia, Brazil, Using Recombinant Chimeric Antigens.

Chagas disease (CD), caused by the parasite Trypanosoma cruzi, is a neglected tropical disease with life-threatening implications. In this study, we conducted a seroepidemiological survey to determine the prevalence and clinical profiles of CD in 217 individuals from an impoverished rural community in Southern Bahia, Brazil. The overall prevalence of CD in the studied community was 0.92%, detected through latent class analysis (LCA). Two individuals tested positive for anti-T. cruzi IgG, both being male farmers. One case was a 22-year-old man born in Camamu, with no evidence of congenital transmission, suggesting other routes of transmission such as vector-borne transmission due to migratory activities. The other case was a 69-year-old man born in São Felipe, who had lived in an adobe/brick house and had a pacemaker due to cardiac involvement caused by CD. The prevalence in this community was lower than expected, given the socioeconomic conditions and environmental factors that contribute to T. cruzi transmission. This could be attributed to the implementation of preventive measures and vector control programs by the Brazilian Government. However, continuous monitoring and surveillance are essential to sustain control efforts and detect any potential re-emergence of the disease. While the overall prevalence was low, the detection of positive cases underscores the need for continued surveillance and control measures in vulnerable populations, such as rural communities. Active surveillance, early diagnosis, and timely treatment are crucial in preventing disease progression and complications, thereby enhancing the effectiveness of screening and treatment programs.

Modulation of circulating cytokine production in alcoholic patients infected with Strongyloides stercoralis.

Strongyloidiasis control is associated with a Th2 immune response. However, alcohol ingestion plays an important role in modulating the immune system. The aim of this study is to evaluate the occurrence of Strongyloides stercoralis infection in alcoholic patients, the levels of circulating cytokines (IFN-γ, IL-2, IL-4, IL-5, IL-10, IL-15 and IL-17), and its correlation with modulation of parasitic load in alcoholic individuals infected with S. stercoralis. A total of 336 alcoholic patients, treated at the Alcoholic Care and Treatment Center were included in this study. The cytokine levels were measured by a commercial ELISA in 80 sera divided into four groups with 20 individuals each: alcoholics infected (ASs+) and not infected (ASs-) with S. stercoralis and non-alcoholics infected (NASs+) and not infected (NASs-) with the helminth. S. stercoralis frequency in alcoholic patients was 16.1% (54/336). The parasitic load varied from 1 to 546 larvae/g of faeces, median and interquartile range (IQR) of 9 and 1.0-62.5 larvae/g of faeces, while in non-alcoholic individuals the parasitic load was less than 10 larvae/g of faeces. Levels of circulating IL-4 were significantly higher in ASs+ when compared with NASs- group (p < .05). An inverse correlation between serum levels of IFN-γ and parasitic load in alcoholic patients infected with S. stercoralis was observed (r = -601; p < 0.01). These results suggest that modulation of IFN-γ production occurs in alcoholic individuals with high parasitic burden.

Cryptosporidium diagnosis in different groups of children and characterization of parasite species.

BACKGROUND: Microscopy and enzyme-linked immunosorbent assay (ELISA) are routinely used for Cryptosporidium diagnosis, without differentiating the parasite species. METHODS: Children's feces were analyzed by modified Ziehl-Neelsen (mZN) and ELISA for Cryptosporidium diagnosis and by polymerase chain reaction-restriction fragment length polymorphism for species identification. RESULTS: Cryptosporidium frequency was 2.6%. The sensitivity and specificity of ELISA were 85.7% and 99.7%, respectively, with excellent concordance with mZN (kappa=0.854). Parasite species were characterized as Cryptosporidium hominis (78.3%), Cryptosporidium felis (17.4%), and Cryptosporidium parvum (4.3%). CONCLUSIONS: Coproantigen ELISA is as efficient as mZN for Cryptosporidium diagnosis. Cryptosporidium genotyping suggests anthroponotic and zoonotic transmission to children.

Evaluation of Strongyloides stercoralis infection in patients with HTLV-1. / Evaluación de la infestación por Strongyloides stercoralis en pacientes con HTLV-1

INTRODUCTION: Individuals infected with the human T-lymphotropic virus type 1 (HTLV-1) may present severe and disseminated forms of Strongyloides stercoralis infection with low therapeutic response. OBJECTIVE: To investigate the S. stercoralis infection and the seroprevalence of IgG anti-S. stercoralis antibodies in individuals infected with HTLV-1 attending the Reference Center for HTLV-1 (CHTLV) in Salvador, Bahia, Brazil. MATERIALS AND METHODS: We conducted a cross-sectional study in 178 HTLV-1-infected individuals treated at the HTLV specialized center between January, 2014, and December, 2018. The parasitological diagnosis of S. stercoralis was performed using the Hoffman, Pons and Janer, agar plate culture, and Baermann-Morais methods. The IgG anti-S. stercoralis detection was performed using an in house enzyme-linked immunosorbent assay (ELISA). The HTLV-1 infection was diagnosed using a commercial ELISA and confirmed by Western blot. RESULTS: The frequency of S. stercoralis infection was 3.4% (6/178). Individuals infected with S. stercoralis from rural areas (50.0%; 3/6) also showed S. stercoralis hyperinfection (>3,000 larvae/gram of feces). The frequency of circulating anti-S. stercoralis IgG antibodies was 20.8% (37/178). CONCLUSIONS: HTLV-1-infected people living in precarious sanitary conditions are more prone to develop severe forms of S. stercoralis infection. Considering the high susceptibility and unfavorable outcome of the infection in these individuals, the serological diagnosis for S. stercoralis should be considered when providing treatment.

Introducción. Los individuos infectados por el virus linfotrópico T humano tipo 1 (HTLV-1) pueden presentar formas graves y diseminadas de infestación por Strongyloides stercoralis con poca mejoría terapéutica. Objetivo. Investigar la infestación por S. stercoralis y la seroprevalencia de IgG anti-S. stercoralis en individuos infectados por HTLV-1 atendidos en el Centro de Referencia para HTLV-1 (CHTLV), en Salvador, Bahía, Brasil. Materiales y métodos. Se hizo un estudio transversal con 178 individuos infectados por HTLV-1 atendidos en el centro especializado de HTLV entre enero de 2014 y diciembre de 2018. El diagnóstico parasitológico de S. stercoralis se hizo mediante los métodos de Hoffman, Pons y Janer, cultivo en placa de agar y Baermann-Morais. Para la detección de IgG anti-S. stercoralis, se utilizó una prueba casera de inmunoabsorción ligada a enzimas (ELISA). La infección por HTLV-1 se diagnosticó usando un ELISA comercial y se confirmó mediante Western blot. Resultados. La frecuencia de infestación por S. stercoralis fue del 3,4 % (6/178). Además, los individuos infestados por S. stercoralis provenientes de la zona rural (50,0 %; 3/6) también mostraron hiperinfestación por S. stercoralis (>3.000 larvas/gramo de heces). La frecuencia de anticuerpos IgG anti-S. stercoralis fue del 20,8 % (37/178). Conclusiones. Las personas infectadas por HTLV-1 que viven en condiciones sanitarias precarias son más propensas a desarrollar formas graves de infestación por S. stercoralis. Teniendo en cuenta la gran vulnerabilidad y el resultado desfavorable de la infección en estos individuos, se debe considerar el diagnóstico serológico de S. stercoralis para administrar el tratamiento.

Evaluation of Strongyloides stercoralis infection in patients with HTLV-1 / Evaluación de la infestación por Strongyloides stercoralis en pacientes con HTLV-1

Introduction: Individuals infected with the human T-lymphotropic virus type 1 (HTLV-1) may present severe and disseminated forms of Strongyloides stercoralis infection with low therapeutic response. Objective: To investigate the S. stercoralis infection and the seroprevalence of IgG anti-S. stercoralis antibodies in individuals infected with HTLV-1 attending the Reference Center for HTLV-1 (CHTLV) in Salvador, Bahia, Brazil. Materials and methods: We conducted a cross-sectional study in 178 HTLV-1-infected individuals treated at the HTLV specialized center between January, 2014, and December, 2018. The parasitological diagnosis of S. stercoralis was performed using the Hoffman, Pons and Janer, agar plate culture, and Baermann-Morais methods. The IgG anti-S. stercoralis detection was performed using an in house enzyme-linked immunosorbent assay (ELISA). The HTLV-1 infection was diagnosed using a commercial ELISA and confirmed by Western blot. Results: The frequency of S. stercoralis infection was 3.4% (6/178). Individuals infected with S . stercoralis from rural areas (50.0%; 3/6) also showed S. stercoralis hyperinfection (>3,000 larvae/gram of feces). The frequency of circulating anti-S. stercoralis IgG antibodies was 20.8% (37/178). Conclusions: HTLV-1-infected people living in precarious sanitary conditions are more prone to develop severe forms of S. stercoralis infection. Considering the high susceptibility and unfavorable outcome of the infection in these individuals, the serological diagnosis for S. stercoralis should be considered when providing treatment.

Introducción. Los individuos infectados por el virus linfotrópico T humano tipo 1 (HTLV-1) pueden presentar formas graves y diseminadas de infestación por Strongyloides stercoralis con poca mejoría terapéutica. Objetivo. Investigar la infestación por S. stercoralis y la seroprevalencia de IgG anti-S. stercoralis en individuos infectados por HTLV-1 atendidos en el Centro de Referencia para HTLV-1 (CHTLV), en Salvador, Bahía, Brasil. Materiales y métodos. Se hizo un estudio transversal con 178 individuos infectados por HTLV-1 atendidos en el centro especializado de HTLV entre enero de 2014 y diciembre de 2018. El diagnóstico parasitológico de S. stercoralis se hizo mediante los métodos de Hoffman, Pons y Janer, cultivo en placa de agar y Baermann-Morais. Para la detección de IgG anti-S. stercoralis, se utilizó una prueba casera de inmunoabsorción ligada a enzimas (ELISA). La infección por HTLV-1 se diagnosticó usando un ELISA comercial y se confirmó mediante Western blot. Resultados. La frecuencia de infestación por S. stercoralis fue del 3,4 % (6/178). Además, los individuos infestados por S. stercoralis provenientes de la zona rural (50,0 %; 3/6) también mostraron hiperinfestación por S. stercoralis (>3.000 larvas/gramo de heces). La frecuencia de anticuerpos IgG anti-S. stercoralis fue del 20,8 % (37/178). Conclusiones. Las personas infectadas por HTLV-1 que viven en condiciones sanitarias precarias son más propensas a desarrollar formas graves de infestación por S. stercoralis. Teniendo en cuenta la gran vulnerabilidad y el resultado desfavorable de la infección en estos individuos, se debe considerar el diagnóstico serológico de S. stercoralis para administrar el tratamiento

Ineffectiveness of TF-Test® and Coproplus® Methods in Strongyloides stercoralis Infection Diagnosis.

PURPOSE: S. stercoralis diagnosis is currently performed by parasitological methods, mainly by Baermann-Moraes (BM), although Agar Plate Culture (APC) presents a higher sensitivity. New techniques, such as TF-Test® and Coproplus® have been suggested as more practical alternatives. The aim of this study was to evaluate the sensitivity of TF-Test® and Coproplus®, compared with APC, BM and Spontaneous Sedimentation (SS) methods. METHODS: One-hundred and forty male alcoholic patients, who provided three stools samples collected on alternate days, were included in this study. The most frequently found parasite was S. stercoralis, 20% (28/140), and the most sensitive method was APC, 96.4% (27/28), followed by BM, 89.3% (25/28) and SS, 57.1% (16/28). TF-Test® and Coproplus® presented a sensitivity of 46.4 (13/28) and 39.3% (11/28), respectively. In samples with a parasitic load of 1-10 larvae/g of feces, which occurred in 39.3% (11/28) of the infected patients, both the TF-Test® and Coproplus® methods demonstrated sensitivities of 18.2% (2/11), while APC and BM methods reached a sensitivity of 100% (11/11) (p < 0.05). For other intestinal helminth infections, TF-Test® and Coproplus® sensitivities were 22.2 (4/18) and 11.1% (2/18), respectively, this being lower than the SS, 66.7% (12/18) (p < 0.05). On the other hand, for protozoa infection diagnosis, TF-Test® and Coproplus® presented the highest sensitivities, 62.2 (46/74) and 43.2% (32/74), respectively. CONCLUSION: TF-Test® and Coproplus® methods presented the lowest sensitivities for S. stercoralis and other helminth infection diagnosis; therefore, they can be indicated for use in parasitological diagnosis, only when associated with other more effective methods of helminth identification.

Cryptosporidium diagnosis in different groups of children and characterization of parasite species

ABSTRACT Background: Microscopy and enzyme-linked immunosorbent assay (ELISA) are routinely used for Cryptosporidium diagnosis, without differentiating the parasite species. Methods: Children's feces were analyzed by modified Ziehl-Neelsen (mZN) and ELISA for Cryptosporidium diagnosis and by polymerase chain reaction-restriction fragment length polymorphism for species identification. Results: Cryptosporidium frequency was 2.6%. The sensitivity and specificity of ELISA were 85.7% and 99.7%, respectively, with excellent concordance with mZN (kappa=0.854). Parasite species were characterized as Cryptosporidium hominis (78.3%), Cryptosporidium felis (17.4%), and Cryptosporidium parvum (4.3%). Conclusions: Coproantigen ELISA is as efficient as mZN for Cryptosporidium diagnosis. Cryptosporidium genotyping suggests anthroponotic and zoonotic transmission to children.

Perfil epidemiológico das parasitoses intestinais em moradores de uma comunidade da Ilha de Boipeba, Bahia, Brasil / Epidemiological profile of intestinal parasites in residents of a community on the island of Boipeba, Bahia, Brazil

Introdução: as parasitoses intestinais constituem-se um importante problema de saúde pública mundial. Estas infecções são mais prevalentes em regiões tropicais impactando na morbimortalidade e aumento nos custos para o sistema de saúde. Objetivo: avaliar a prevalência das enteroparasitoses e sua associação com as condições socioeconômicas, sanitárias, ambientais e hábitos de vida em uma comunidade costeira do Nordeste brasileiro. Metodologia: estudo epidemiológico, descritivo e transversal, realizado de modo não probabilístico entre março a junho de 2017, com 105 moradores da Ilha de Boipeba, localizada no Sul da Bahia. O exame parasitológico de fezes foi realizado pelos métodos de sedimentação espontânea, Baermann-Moraes e FAUST. Um questionário foi aplicado para avaliar o perfil sociodemográfico da população. Resultados: do total de indivíduos avaliados, 52,4% eram do sexo feminino e 57,1% tinham entre 15 a 59 anos. Todos os indivíduos possuíam água encanada, porém não tratada, enquanto 91,4% referiu ingerir vegetais crus e 45,7% não higienizavam as mãos antes as refeições. Sintomas gastrointestinais foram relatados em 82,8% dos indivíduos e infecções enteroparasitárias foram diagnosticadas em 69,6%. Os parasitos mais frequentemente encontrados foram Ancilostomídeo (18,1%) e Entamoeba coli (43,8%). O principal fator de risco potencial para contrair a infecção por ancilostomídeos foi a não existência de poço artesiano na residência (RP=4,35), enquanto para Trichuris trichiura foi não dispor de pia no banheiro (RP=3,82). Conclusão: a comunidade analisada apresentou elevada prevalência de enteroparasitoses. Os hábitos precários de higiene e de acesso à água tratada, associados às condições ambientais e climáticas do local, podem ter contribuído para a elevada transmissão de geohelmintos observada.

Introduction: Intestinal parasitic infections are an important public health problem worldwide. They are more prevalent in tropical regions impacting in morbidity and mortality and costs for the health system. Objective: To evaluate the prevalence of enteroparasitosis and its association with socioeconomic, sanitary and environmental conditions and lifestyle habits in a coastal community in the Northeast Brazil. Methodology: This is an epidemiological, descriptive and cross-sectional study, carried out in a non-probabilistic manner between March and June 2017, with 105 residents of Boipeba Island in the Southern Bahia. The parasitological examination of feces was carried out by the methods of spontaneous sedimentation, Baermann-Moraes and FAUST. A questionnaire was applied to assess the sociodemographic profile of the population. Results: Of the total of individuals evaluated, 52.4% were female and 57.1% were between 15 and 59 years old. All individuals had piped, but untreated water, while 91.4% reported eating raw vegetables and 45.7% did not wash their hands before meals. Gastrointestinal symptoms were observed in 82.8% individuals and 69.6% were diagnosed with enteroparasitic infections. The most frequent parasites were the hookworm (18.1%) and Entamoeba coli (43.8%). The main potential risk factor for hookworm infection was the non-existence of an artesian well in the residence (PR=4.35) and Trichuris trichiura it was not having a sink in the toilet (PR=3.82). Conclusion: The analyzed community has a high prevalence of enteroparasitosis, in addition to environmental and climatic conditions that contribute to the transmission of these infections.

The Predominance of Giardia duodenalis AII sub-assemblage in young children from Salvador, Bahia, Brazil. / Predominio del subconjunto AII de Giardia duodenalis en niños pequeños de Salvador, Bahía, Brasil

INTRODUCTION: Giardia duodenalis is an intestinal protozoan with a high prevalence in children of developing countries. Molecular studies revealed a great genetic diversity of G. duodenalis, with assemblages A and B found mainly in humans. Despite its importance, the information on the molecular epidemiology of human giardiasis is still limited in Brazil. OBJECTIVE: To characterize G. duodenalis molecular isolates in children from Salvador, Bahia, Brazil. MATERIALS AND METHODS: Giardia duodenalis positive fecal samples were obtained from 71 children from two day care centers and 39 users of a clinical analysis laboratory. Samples were analyzed by PCR-RFLP of the glutamate dehydrogenase (gdh) and beta-giardin genes and by the sequencing of beta-giardin. RESULTS: Of the 110 G. duodenalis samples, 80 (72.7%) amplified one or both target genes. Of these, 62 (77.5 %) were identified as assemblage A and 18 (22.5%) as assemblage B. The subassemblage AII was identified in 58.8% (n=47) of isolates followed by the sub-assemblage AI (18.8%, n=15), BIV (11.2%, n=9), and BIII (5.0%, n=4). The AII sub-assemblage was the most frequent in children of both day care centers whereas AI was found only in the group attended at the clinical laboratory. Sub-assemblage AII predominated in children under two years. CONCLUSIONS: The higher frequency of AII sub-assemblage suggests that anthroponotic transmission is more common in Salvador, but that zoonotic transmission pathways are also present and a change in susceptibility to different molecular patterns of Giardia may occur during child growth.

Introducción. Giardia duodenalis es un protozoo intestinal de gran prevalencia en los niños de los países en desarrollo. En estudios moleculares se ha evidenciado la gran diversidad genética de G. duodenalis y se han identificado los conjuntos A y B, principalmente en humanos. A pesar de su importancia, el conocimiento de la epidemiología molecular de la giardiasis humana aún es limitado en Brasil. Objetivo. Caracterizar los aislamientos moleculares de G. duodenalis de muestras tomadas a niños de Salvador, Bahía, Brasil. Materiales y métodos. Las muestras fecales positivas para G. duodenalis se obtuvieron de 71 niños de dos guarderías y de 39 usuarios de un laboratorio de análisis clínicos. Las muestras se analizaron mediante PCR-RFLP de los genes gdh y beta-giardin, y secuenciación de beta-giardin. Resultados. De las 110 muestras de G. duodenalis, en 80 (72,7 %) se amplificaron uno o ambos genes. De estos, 62 (77,5 %) se identificaron como pertenecientes al conjunto A y 18 (22,5 %) al B. El subconjunto AII se identificó en el 58,8 % (n=47) de los aislamientos, seguido del AI en el 18,8% (n=15), el BIV en el 11,2% (n=9) y el BIII en el 5,0% (n=4). El subconjunto AII fue el más frecuente en los niños de ambas guarderías, en tanto que el AI solo se encontró en el grupo atendido en el laboratorio clínico. El subconjunto AII predominó en los niños menores de dos años. Conclusiones. La mayor frecuencia del subconjunto AII sugiere que la transmisión antroponótica es más común en Salvador, pero también existen vías de transmisión zoonóticas, y que pueden ocurrir cambios en la sensibilidad frente a diferentes patrones moleculares de Giardia durante el crecimiento infantil.

Predominance of Giardia duodenalis AII sub-assemblage in young children from Salvador, Bahia, Brazil / Predominio del subconjunto AII de Giardia duodenalis en niños pequeños de Salvador, Bahía, Brasil

Introduction. Giardia duodenalis is an intestinal protozoan with a high prevalence in children of developing countries. Molecular studies revealed a great genetic diversity of G. duodenalis, with assemblages A and B found mainly in humans. Despite its importance, the information on the molecular epidemiology of human giardiasis is still limited in Brazil. Objective. To characterize G. duodenalis molecular isolates in children from Salvador, Bahia, Brazil. Materials and methods. Giardia duodenalis positive fecal samples were obtained from 71 children from two day care centers and 39 users of a clinical analysis laboratory. Samples were analyzed by PCR-RFLP of the glutamate dehydrogenase (gdh) and beta-giardin genes and by the sequencing of beta-giardin. Results. Of the 110 G. duodenalis samples, 80 (72.7%) amplified one or both target genes. Of these, 62 (77.5 %) were identified as assemblage A and 18 (22.5%) as assemblage B. The subassemblage AII was identified in 58.8% (n=47) of isolates followed by the sub-assemblage AI (18.8%, n=15), BIV (11.2%, n=9), and BIII (5.0%, n=4). The AII sub-assemblage was the most frequent in children of both day care centers whereas AI was found only in the group attended at the clinical laboratory. Sub-assemblage AII predominated in children under two years. Conclusions. The higher frequency of AII sub-assemblage suggests that anthroponotic transmission is more common in Salvador, but that zoonotic transmission pathways are also present and a change in susceptibility to different molecular patterns of Giardia may occur during child growth.

Introducción. Giardia duodenalis es un protozoo intestinal de gran prevalencia en los niños de los países en desarrollo. En estudios moleculares se ha evidenciado la gran diversidad genética de G. duodenalis y se han identificado los conjuntos A y B, principalmente en humanos. A pesar de su importancia, el conocimiento de la epidemiología molecular de la giardiasis humana aún es limitado en Brasil. Objetivo. Caracterizar los aislamientos moleculares de G. duodenalis de muestras tomadas a niños de Salvador, Bahía, Brasil. Materiales y métodos. Las muestras fecales positivas para G. duodenalis se obtuvieron de 71 niños de dos guarderías y de 39 usuarios de un laboratorio de análisis clínicos. Las muestras se analizaron mediante PCR-RFLP de los genes gdh y beta-giardin, y secuenciación de beta-giardin. Resultados. De las 110 muestras de G. duodenalis, en 80 (72,7 %) se amplificaron uno o ambos genes. De estos, 62 (77,5 %) se identificaron como pertenecientes al conjunto A y 18 (22,5 %) al B. El subconjunto AII se identificó en el 58,8 % (n=47) de los aislamientos, seguido del AI en el 18,8% (n=15), el BIV en el 11,2% (n=9) y el BIII en el 5,0% (n=4). El subconjunto AII fue el más frecuente en los niños de ambas guarderías, en tanto que el AI solo se encontró en el grupo atendido en el laboratorio clínico. El subconjunto AII predominó en los niños menores de dos años. Conclusiones. La mayor frecuencia del subconjunto AII sugiere que la transmisión antroponótica es más común en Salvador, pero también existen vías de transmisión zoonóticas, y que pueden ocurrir cambios en la sensibilidad frente a diferentes patrones moleculares de Giardia durante el crecimiento infantil.

Specific IgG and IgA Antibody Reactivities in Sera of Children by Enzyme-Linked Immunoassay and Comparison With Giardia duodenalis Diagnosis in Feces.

BACKGROUND: Giardia duodenalis is conventionally diagnosed in fecal samples using parasitological methods. However, sensitivity is poor when only a single sample is analyzed, due to intermittent excretion of cysts in feces. Alternatively, the serum antibodies to G. duodenalis can be used for parasite diagnosis and epidemiological studies to determine previous exposure. We compared the rate of G. duodenalis infection between serum anti-Giardia IgG and IgA antibodies and fecal examination in Brazilian children. METHODS: Fecal and serum samples were tested from 287 children at a clinical laboratory and from 187 children at daycare centers. Fecal samples were processed using conventional parasitological methods and coproantigen detection for Giardia diagnosis. Serum samples were tested using an in-house ELISA for detection of anti-Giardia IgG and IgA. RESULTS: G. duodenalis was found in 8.2% (N=39) of the 474 children analyzed. The sensitivity and specificity of ELISA were 80.0% and 90.0% for IgG and 80.0% and 83.3% for IgA, respectively. The total positivity rate of anti-Giardia IgG and IgA in the sera was 13.9% (N=66) and 23.6% (N=112). The agreement between the positivity of specific antibodies and the detection of G. duodenalis in feces was moderate for ELISA-IgG, kappa index (95% CI)=0.543 (0.422-0.664), and mild for ELISA-IgA, kappa index (95% CI)=0.283 (0.162-0.404). Among the children infected with other enteroparasites, 11.6% (N=10) and 24.4% (N=21) showed reactivity to anti-Giardia IgG and to IgA, respectively. This cross-reactivity was more frequent in samples from children infected with Endolimax nana and Entamoeba coli. CONCLUSIONS: The higher frequency of specific antibody reactivity compared with G. duodenalis diagnosis in feces could reflect continuous exposure of children to G. duodenalis infection, resulting in long-lasting immunological memory and/or cross-reactivity with other intestinal amoebas.

Alcohol consumption alters anti-Strongyloides stercoralis antibodies production.

Individuals infected with Strongyloides stercoralis have been reported to produce different immunoglobulins isotypes, yet few studies have evaluated their use in strongyloidiasis diagnosis. The aim of this work was to evaluate the immunoreactivity of different classes and subclasses of anti-S. stercoralis circulating antibodies in alcoholic patients by ELISA and to perform immunoblotting in samples with discordant results between parasitological and immunological methods. 345 male patients with a clinical diagnosis of alcoholism hospitalized at a reference center for alcoholics in Salvador, Bahia, Brazil, were included in this study. The fecal samples were examined by three different parasitological methods (spontaneous sedimentation, Baermann-Moraes and Agar Plate Culture methods). The ELISA was performed for the detection of IgG, IgG1, IgG4, IgE and IgA1 anti-S. stercoralis. Immunoblotting, for the detection of specific IgA1, was used to elucidate discordant results between parasitological and immunological methods. S. stercoralis infection frequency in alcoholic patients by parasitological methods was 21.4% (74/345). Although IgE-ELISA demonstrated a high sensitivity and specificity in non-alcoholic patients, about 30% (22/74) of alcoholics with larvae in feces were negative. IgG1-ELISA detected the lowest frequency of antibodies in alcoholic patients with larvae in feces, only 57% (42/74). IgG4-ELISA was the best assay for S. stercoralis infection immunodiagnosis. Immunoreactivity in the immunoblotting for IgA1 at 90, 75, 26 and/or 17 kDa bands was observed in 92% (33/36) of alcoholics with larvae excretion and negative ELISA for one or more antibody isotypes. In conclusion, IgG4-ELISA showed the highest sensitivity and specificity, thus demonstrating its superiority for strongyloidiasis immunodiagnosis in alcoholic and non-alcoholic individuals. Both, IgE and IgG1-ELISA presented high sensitivities and specificities for S. stercoralis infection diagnosis in non-alcoholics, however there was low reactivity in alcoholic individuals. This can be associated with an increased susceptibility to severe strongyloidiasis in these patients. IgA1-immunoblotting can be used to confirm S. stercoralis infection when there are discordant results between parasitological methods and ELISA.

Relação entre genótipo e insuficiência pancreática em crianças e adolescentes com fibrose cística de um centro de referência no Brasil / Relationship between genotype and pancreatic insufficiency in children and adolescents with cystic fibrosis in a referral center in Brazil

Introdução: fibrose cística (FC) é uma doença genética que culmina em alterações na proteína transmembrana CFTR, resultando na produção de muco mais espesso em diversos órgãos, destacando-se os tratos respiratório e digestório. A insuficiência pancreática (IP) acomete até 95% dos pacientes com FC. Objetivos: determinar a frequência de IP através da dosagem de elastase fecal-1 (EF-1) e compará-la com o genótipo de pacientes com FC assistidos em um centro de referência. Metodologia: foi realizado um estudo transversal, incluindo-se pacientes com FC de 0 a 20 anos. Após a inclusão dos sujeitos à pesquisa, foi realizada consulta ao prontuário para a obtenção de dados clinicos e demograficos e amostras de fezes foram obtidas para dosagem da (EF-1). Os pacientes foram submetidos à análise molecular das mutações por métodos convencionais, através da extração do DNA em sangue periférico. Quando duas mutações patológicas não foram identificadas, o sequenciamento de nova geração com utilização da plataforma Illumina HiSeq foi realizado em amostras da mucosa oral. Resultados: foram incluídos 31 pacientes, 17 (54,8%) do sexo feminino, mediana de idade de 10 anos, e apenas um paciente foi classificado como branco. Vinte e dois (70,9%) pacientes apresentaram dosagem de EF-1 inferior a 200 µg/g, compatível com o diagnóstico de IP. Destes, 21 (95,4%) apresentaram dosagem de EF-1 menor ou igual a 15µg/g, caracteristica de IP grave. Todos os pacientes com IP apresentavam duas mutações de classes I a III. Conclusão: a IP foi identificada em 70% dos pacientes, ocorrendo em todos os pacientes com duas mutações de classe I-III.

Introduction: cystic fibrosis (CF) is a genetic disease that culminates in alterations in the CFTR transmembrane protein, resulting in the production of thicker mucus in various organs, especially the respiratory and digestive tract. Pancreatic insufficiency (PI) affects up to 95% of CF patients. Objectives: To determine the frequency of PI by measuring fecal elastase-1 (FE-1) and comparing it with the genotype of CF patients assisted at a referral Center. Methodology: a cross-sectional study was conducted, including patients with CF from 0 to 20 years. After the inclusion of the subjects to the research, medical records were consulted to obtain clinical and demographic data and stool samples were obtained for the measurement of (FE-1). Patients were submitted to molecular analysis of mutations by conventional methods by DNA extraction in peripheral blood. When two pathological mutations were not identified, next-generation sequencing using the Illumina HiSeq platform was performed on oral mucosa samples. Results: thirty one patients were included, 17 (54.8%) female, median age 10 years, and only one patient was classified as white. Twenty-two (70.9%) patients had an FE-1 dosage of less than 200 µg / g, compatible with the diagnosis of pancreatic insufficiency (PI). Of these, 21 (95,4%) had an EF-1 dosage less than or equal to 15µg / g, characteristic of severe PI. All patients with two mutations class I to III were PI. Conclusion: PI was identified in 70% of patients, occurring in all patients with class I-III mutations.

Enteroparasitoses e aspectos socioeconômicos em pacientes alcoolistas / Intestinal parasites and socioeconomic aspects of alcoholic patients

Introdução: as enteroparasitoses constituem um problema de saúde pública que atinge as populações mais vulneráveis. O alcoolismo é um problema que afeta milhões de pessoas em todo o mundo, apresenta efeitos nocivos à saúde dos indivíduos e predispõe à infecção por S. stercoralis e às formas mais graves da estrongiloidíase. Objetivo: avaliar a prevalência da infecção das enteroparasitoses, bem como fatores socioeconômicos e sanitários de pacientes alcoolistas atendidos em um centro de tratamento especializado em Salvador, Bahia. Metodologia: trata-se de um estudo transversal, realizado com pacientes alcoolistas (n=277), do sexo masculino, atendidos em um centro de tratamento entre julho de 2014 e junho de 2017. O estudo foi realizado através da aplicação de um questionário estruturado para obtenção de dados socioeconômicos, demográficos e sanitários, sendo solicitadas, ainda, pelo menos duas amostras de fezes em dias alternados. O diagnóstico parasitológico foi realizado pelos métodos de sedimentação espontânea, Baermann-Moraes e cultura em placa de ágar. Resultados: a média de idade dos pacientes inclusos foi de 44,8 ± 9,5 anos. Verificouse que 35,7% dos pacientes estavam infectados com algum enteroparasito e, desses, 30,3% eram monoparasitados. Os parasitos mais frequentes foram S. stercoralis, Endolimax nana e ancilostomídeos, correspondendo 16,6%, 11,2% e 5,8%, respectivamente. Conclusão: dessa forma, S. stercoralis foi o parasito mais frequente, e a associação entre a infecção por esse parasito e o alcoolismo pode levar à estrongiloidíase grave. A elevada frequência de enteroparasitoses nesses pacientes, principalmente por protozoários, deve-se à ausência de higiene pessoal, pois esses indivíduos são suscetíveis à infecção oral fecal. A implementação de medidas de saneamento básico e de campanhas de conscientização para prevenção de infecções parasitárias é imprescindível para a saúde das populações mais vulneráveis.

Introduction: intestinal parasitoses are a public health issue that notably affects vulnerable populations. Alcoholism is a problem that affects millions worldwide by causing damaging effects to the health of individuals as it predisposes them to that infection through stercralisàs and more evolved forms of strongyloidiasis. Objective: evaluate the prevalence of intestinal parasite infections as well as socioeconomic and sanitation factors in a population of alcoholic patients at a specialized treatment facility in Salvador, Bahia. Methodology: this cross-sectional study was carried out with male alcoholic patients (n=277) at a treatment facility from July/2014 to June/2017. The research data were collected through a structured questionnaire aimed to obtain socioeconomic, demographic and sanitation information. Stool tests were ordered in alternate days. The parasitological diagnosis was based on methods of spontaneous sedimentation, Baermann-Moraes and Agar plate growth medium. Results: the patients' average age was 44,8 ± 9,5 years. A total of 35% of the patients was infected with a type of enteroparasite, of whom 30,3% was mono-infected. The most commonly found parasites were S. stercoralis, Endolimax nana and hookworm, corresponding to 16,6%, 11,2% e 5,8%, respectively. Conclusion: as such, S. Stercoralis was the most frequent parasite in this population and the association between the infection by this parasite and alcoholism may lead to severe strongyloidiasis. The high rates of enteroparasitism in those patients, particularly protozoa, are due to the lack of adequate personal hygiene, given those individuals are prone to acquire infections transmitted through the oral fecal route. An implementation of public health sanitation measures and the launch of public awareness campaigns in order to prevent parasite infections are vital to the health of vulnerable populations.

Case Report: Strongyloides stercoralis Hyperinfection in a Patient with HTLV-1: An Infection with Filariform and Rhabditiform Larvae, Eggs, and Free-Living Adult Females Output.

Strongyloides stercoralis is the main etiological agent of human strongyloidiasis. Severe strongyloidiasis is commonly associated to alcoholism, corticostereoid use, and human T cell lymphotropic virus type 1 (HTLV-1) coinfection. Herein, we report a case of a 13-year-old boy coinfected with S. stercoralis and HTLV-1, excreting several parasitic forms in the stool. The parasitological examination of his feces showed a large amount of filariform (about 3,000 larvae per gram of feces) and rhabditiform larvae (about 2,000 larvae per gram of feces). In addition, free-living adult females (about 50 parasites per gram of feces) and eggs (about 60 eggs per gram of feces) were detected. The main laboratory findings pointed to high immunoglobulin E (IgE) levels (228 UI/mL) and eosinophila (11.6%). The patient was treated with three courses of ivermectin (200 µg/kg twice, 2 weeks apart), achieving the parasitological cure. An increase of about 19 times in interleucin (IL)-17 level was observed following the parasitological cure, in addition to a decrease in the white blood cell, eosinophil counts, and IgE levels. This is the first case report, to our knowledge, in which an S. stercoralis adult free-living female was described in human feces and where an increase in IL-17 levels after Strongyloides treatment in a HTLV-1 coinfected individual was observed. This finding raises the need for further studies about IL-17 immunomodulation in S. stercoralis and HTLV-1 coinfected patients.

Alterations in serum paraoxonase-1 activity and lipid profile in chronic alcoholic patients infected with Strongyloides stercoralis.

The objective of this study was to investigate paraoxonase-1 (PON1) activity, cortisol levels, and the lipid profile in the sera of alcoholic and non-alcoholic Strongyloides stercoralis-infected and uninfected individuals in a sample of 276 individuals attended at the National Health System in Salvador, Bahia, Brazil. The activity of PON1 was measured by the Beltowski method, serum lipids, and cortisol levels using commercial kits. PON1 activity was low in both alcoholic and non-alcoholic individuals infected with S. stercoralis. A positive correlation was observed between PON1 activity and cortisol concentration in alcoholic individuals who were not infected with S. stercoralis; whereas a negative correlation occurred in S. stercoralis-infected nonalcoholic individuals. The levels of triglycerides, LDL-C, and VLDL-C in S. stercoralis-infected alcoholic individuals were significantly lower than in uninfected alcoholic individuals. The high level of HDL-C and the low level of LDL-C, VLDL, triglycerides and PON1 activity in alcoholic patients infected with S. stercoralis evidenced an anti-atherogenic pattern.

[Concordance between the zinc sulphate flotation and centrifugal sedimentation methods for the diagnosis of intestinal parasites].

INTRODUCTION: The diagnosis of intestinal parasitic infections depends on the parasite load, the specific gravity density of the parasite eggs, oocysts or cysts, and the density and viscosity of flotation or sedimentation medium where faeces are processed. OBJECTIVE: To evaluate the concordance between zinc sulphate flotation and centrifugal sedimentation in the recovery of parasites in faecal samples of children. MATERIALS AND METHODS: Faecal samples of 330 children from day care centers were evaluated by zinc sulphate flotation and centrifugal sedimentation techniques. The frequencies of detection of parasites by each method were determined and the agreement between the diagnostic techniques was evaluated using the kappa index, with 95% confidence intervals. RESULTS: The faecal flotation in zinc sulphate diagnosed significantly more cases of Trichuris trichiura infection when compared to centrifugal sedimentation (39/330; 11.8% vs. 13/330; 3.9%, p<0.001), with low diagnostic concordance between methods (kappa=0.264; 95% CI: 0.102-0.427). Moreover, all positive samples for Enterobius vermicularis eggs (n=5) and Strongyloides stercoralis larvae (n=3) were diagnosed only by zinc sulphate. No statistical differences were observed between methods for protozoa identification. CONCLUSIONS: The results showed that centrifugal flotation in zinc sulphate solution was significantly more likely to detect light helminths eggs such as those of T. trichiura and E. vermicularis in faeces than the centrifugal sedimentation process.