COVID-19 and the gastrointestinal tract: what do we already know? / COVID-19 e o trato gastrintestinal: o que já sabemos?

ABSTRACT The new coronavirus disease pandemic is defining 2020, with almost 17.5 million infected individuals and 700 thousand deaths up to beginning of August. It is caused by SARS-CoV-2 and the transmission is through the respiratory tract. Those infected may be asymptomatic, present typical symptoms (fever, dry cough and dyspnea), gastrointestinal symptoms (diarrhea, nausea, vomiting and abdominal pain) and viral RNA in stools. The objective of this work was to review the literature related to the prevalence of gastrointestinal symptoms, and to check the possibility of fecal-oral transmission. We searched PubMed® database on COVID-19 and gastrointestinal tract and selected articles using the PRISMA method. We eliminated articles based on titles and abstracts, small number of patients and the mechanism of infection, leaving 14 studies. Comorbidities and laboratory alterations (elevation of hepatic aminotransferases and bilirubin) were related to worsening of the disease. The prevalence of gastrointestinal symptoms ranged from 6.8% to 61.3%, including diarrhea (8.14% to 33.7%), nausea/vomiting (1.53% to 26.4%), anorexia (12.1% to 40.0%) and abdominal pain (0% to 14.5%). The presence of viral RNA in stools was rarely tested, but positive in 0% to 48.1%. The gastrointestinal tract is affected by COVID-19, causing specific symptoms, laboratory alterations and viral presence in the feces. However, the results of prevalence and possibility of fecal-oral transmission were varied, requiring further studies for more assertive conclusions. It is important that healthcare professionals draw attention to this fact, since these changes can help make diagnosis and initiate early treatment.

RESUMO Com quase 17,5 milhões de infectados e 700 mil mortos até o início de agosto no mundo, a pandemia do novo coronavírus está marcando o ano de 2020. O agente causador da doença é o vírus SARS-CoV-2, e a transmissão é por via respiratória. Os infectados podem ser assintomáticos, apresentar sintomas típicos (febre, tosse seca e dispneia), sintomas gastrintestinais (diarreia, náusea, vômito e dor abdominal) e RNA viral nas fezes. O objetivo deste trabalho foi revisar a literatura relacionada com a prevalência dos sintomas gastrintestinais, e verificar se é possível a transmissão fecal-oral da doença. Fizemos uma pesquisa na base de dados PubMed® sobre a COVID-19 e o trato gastrintestinal, selecionando artigos pelo método PRISMA. Eliminamos artigos com base em títulos e resumos, quantidade pequena de pacientes e sobre mecanismo de infecção, restando 14 estudos. Comorbidades e alterações laboratoriais (elevação de aminotransferases hepáticas e bilirrubina) foram relacionadas com piora da doença. A prevalência de sintomas gastrintestinais variou entre 6,8% e 61,3%, sendo eles diarreia (8,14% a 33,7%), náusea/vômito (1,53% a 26,4%), anorexia (12,1% a 40,0%) e dor abdominal (0% a 14,5%). A presença do RNA viral foi pouco testada, mas foi positiva entre 0% a 48,1%. O trato gastrintestinal é muito acometido pela COVID-19, provocando sintomas específicos, alterações laboratoriais e presença viral nas fezes. Contudo, os resultados de prevalência e a possibilidade de transmissão fecal-oral foram variados, necessitando de estudos maiores para conclusões mais assertivas. É importante a atenção de profissionais da saúde a isso, visto que essas alterações podem ajudar no diagnóstico e a iniciar tratamento precoce.

Efecto de la terapia con probióticos/prebióticos sobre la reconstitución del tejido linfoide asociado a la mucosa gastrointestinal durante la infección por el virus de la inmunodeficiencia humana-1 / Effects of prebiotics and probiotics on gastrointestinal tract lymphoid tissue in hiv infected patients

HIV infection induces alterations in almost all immune cell populations, mainly in CD4+ T cells, leading to the development of opportunistic infections. The gut-associated lymphoid tissue (GALT) constitutes the most important site for viral replication, because the main target cells, memory T-cells, reside in this tissue. It is currently known that alterations in GALT are critical during the course of the infection, as HIV-1 induces loss of tissue integrity and promotes translocation of microbial products from the intestinal lumen to the systemic circulation, leading to a persistent immune activation state and immune exhaustion. Although antiretroviral treatment decreases viral load and substantially improves the prognosis of the infection, the alterations in GALT remains, having a great impact on the ability to establish effective immune responses. This emphasizes the importance of developing new therapeutic alternatives that may promote structural and functional integrity of this tissue. In this regard, therapy with probiotics/prebiotics has beneficial effects in GALT, mainly in syndromes characterized by intestinal dysbiosis, including the HIV-1 infection. In these patients, the consumption of probiotics/prebiotics decreased microbial products in plasma and CD4+ T cell activation, increased CD4+ T cell frequency, in particular Th17, and improved the intestinal flora. In this review, the most important findings on the potential impact of the probiotics/prebiotics therapy are discussed.

The Gut and Lung Morphometry in Experimental and Natural Lineage 1 Variant of Peste des Petits Ruminants Virus Infection in Nigerian Goats / Morfometría Intestinal y Pulmonar en la Infección Natural y Experimental del Virus Peste des petits ruminants del linaje 1 en Cabras de Nigeria

The lung and gut morphometry in both natural and experimental Peste de petit ruminant (PPR) virus which are scanty in literature hence the need for this study. The goats that were submitted for necropsy in the Department of Veterinary Pathology University of Ibadan between 2009 and 2010 and the gross pathological diagnosis were PPR were enrolled in this study. The degree of pneumonia as a percentage of the total lung volume was estimated using standard methods. The gut morphometry of goats experimentally infected with PPR virus was also used. Student "T" test was used for the test of significance in evaluating the effect of age, sex and the lung consolidation pattern in natural PPR and analysis of the gut morphometry. Complicated PPR had significant higher pulmonary consolidation when compared with the uncomplicated PPR (p< 0.05). The pulmonary consolidation was significantly higher on the right lung with a mean percentage value of 6.54 than the left lung (p< 0.05). The caudal lobe was more consolidated than the cranial and middle lobes in natural PPR. The pulmonary consolidation was more in goats less than a year, while the buck had a significantly higher pulmonary consolidation than the does (p< 0.05). There was no significant difference in the mean length of the villi and width of the villi of PPR virus infected goats when compared to the control, however a significant difference was observed in the cryptal depth (p< 0.05). There was a significant difference in the mean villi length and cryptal depth of goats with complicated PPR (Mannheimia hemolytica) infected goats (p< 0.05) relative to the control. From this study, it showed that most natural PPR were complicated with bacteria and this complication may have contributed to the fatality associated with PPR especially those caused by lineage 1 viruses. This study also showed that secondary bacterial involvement in course of PPR affect the gut morphometry and that could account for the severity of intestinal lesion commonly observed with field PPR in Nigerian goats.

La morfometría del pulmón y el intestino en la infección del virus Peste des petits ruminants (PRR) de forma natural así como experimental es escaza en la literatura, de ahí la necesidad de este estudio. Fueron incluidas en este estudio las cabras que fueron sometidas a autopsia en el Departamento de Patología Veterinaria de la Universidad de Ibadan entre 2009 y 2010, con diagnóstico patológico macroscópico de PPR. El grado de neumonía como porcentaje del volumen pulmonar total fue estimado mediante los métodos estándar. También fue determinada la morfometría del intestino de las cabras infectadas experimentalmente con el virus PPR. Se utilizó la prueba "T" de Student para determinar la significancia en la evaluación de los efectos de edad, sexo, patrón de consolidación pulmonar en PPR natural y análisis de la morfometría intestinal. La PPR complicada tuvo una consolidación pulmonar altamente significativa en comparación con la PPR no complicada (p <0,05). La consolidación pulmonar fue significativamente mayor en el pulmón derecho, con un valor porcentaje promedio de 6,54 en comparación al pulmón izquierdo (p <0,05). El lóbulo caudal fue más consolidado que los lóbulos craneal y medio en presencia del PPR natural. La consolidación pulmonar fue más frecuente en caprinos menores de un año, mientras que los machos cabríos tuvieron una consolidación pulmonar significativamente más alta (p <0,05). No hubo diferencias significativas en la longitud y ancho promedio de las vellosidades en cabras infectadas con PPR en comparación con el control, pero se observó una diferencia significativa en la profundidad de las criptas (p <0,05). Hubo diferencia significativa en la longitud de las vellosidades y la profundidad media de las criptas en las cabras infectadas con PPR complicada (Mannheimia haemolytica) (p <0,05) en relación al control. A partir de este estudio, se demostró que las infecciones con PPR natural se complicaron con bacterias, y estas complicaciones pueden haber contribuido a la mortalidad asociada el PPR, especialmente las causadas por el virus del linaje 1. Este estudio también mostró que la participación bacteriana secundaria en el curso de la PPR afecta la morfometría intestinal y que podría dar cuenta de la gravedad de la lesión intestinal observada comúnmente en la infección de PPR en cabras de Nigeria.

BVDV induced gastro-neuropathy outbreak in a feedlot calves around Tehran [Iran]

An outbreak of a lethal disease was reported in 4-6-month-old Holstein calves in a feedlot around Tehran. The signs of central nervous system and gastrointestinal system [GI] involvement were observed in the diseased animals. Necropsy samples of GI, liver, kidney, spleen and lung from 3 died animals were prepared for histopathological examination. Blood and formalin-fixed ear notch samples of 6 calves were submitted for RT-PCR, antigen-capture ELISA [ACE] and immunohistochemistry [IHC] for the detection of BVDV. The results of ACE on buffy coats were negative but RT-PCR of all 6 cases and IHC of 4 cases were positive for BVDV infection. Based on the clinical signs and pathological findings in the GI system and brain, we strongly suggest that the BVDV may represent a gastro-neuropathogen strain. To the best of our knowledge, this is the first outbreak of gastro-neuropathogenic BVDV infection in Iran, which may be acquired postnatally