PATHOGENICITY OF Blastocystis sp. TO THE GASTROINTESTINAL TRACT OF MICE: RELATIONSHIP BETWEEN INOCULUM SIZE AND PERIOD OF INFECTION / Histopatogenicidade de Blastocystis sp. para o trato gastrointestinal de camundongos: relação com inóculo e tempo de infecção

The pathogenic potential of Blastocystis sp. in experimental models requires further investigation. In this work, the pathogenicity of this parasite in the gastrointestinal tract of male Swiss mice was evaluated according to the inoculum size and period of infection. Animals were infected intragastrically, with 100, 500, 1,000, 5,000 and 10,000 Blastocystis sp. vacuolar forms obtained from a mixture of eight human isolates cultured axenically in Jones' medium. After seven, 14, 21, 28 and 60 days of infection, the animals were sacrificed and fragments of the small intestine (duodenum), large intestine, and cecum were subjected to histopathological analysis. Blastocystis sp. triggered an inflammatory response in the different tissues analyzed, with a predominance of mononuclear cells. The parasite was found in the muscular layer of the cecum, showing its invasive character. Larger inocula triggered inflammatory processes earlier (seven days) than smaller ones (from 21 days). We conclude that, in the proposed model, the pathogenicity of Blastocystis sp. isolates that were studied is related to inoculum size and period of infection.

Pouco é sabido sobre o potencial patogênico de Blastocystis sp. em modelos experimentais. Neste trabalho a patogenicidade desse parasito para o trato gastrointestinal de camundongos Swiss machos foi avaliada de acordo com o inóculo e tempo de infecção. Os animais foram infectados, via intragástrica, com 100, 500, 1.000, 5.000 e 10.000 formas vacuolares de Blastocystis sp. obtidos a partir de uma mistura de oito isolados humanos cultivados axenicamente em meio Jones. Após 7, 14, 21, 28 e 60 dias de infecção os animais foram sacrificados e fragmentos do intestino delgado (duodeno), grosso e ceco foram retirados para análise histopatológica. Blastocystis sp. desencadeou resposta inflamatória nos diferentes tecidos analisados, com predominância de infiltrado mononuclear. No ceco o parasito foi encontrado na túnica muscular mostrando seu caráter invasivo. Inóculos maiores desencadearam processos inflamatórios mais precocemente (7 dias) e inóculos menores mais tardiamente (a partir de 21 dias). Conclui-se que no modelo proposto a patogenicidade dos isolados de Blastocystis sp. estudados tem relação com o inóculo e tempo de infecção.

Cytokine expression in the duodenal mucosa of patients with visceral leishmaniasis / Expressão de citocinas na mucosa duodenal de pacientes com leishmaniose visceral

INTRODUCTION: Visceral leishmaniasis (VL) is a neglected tropical disease with a complex immune response in different organs. This pattern of organ-specific immune response has never been evaluated in the gastrointestinal tract. The aim of this study was to determine the in situ immune response in duodenal biopsies on patients with VL. METHODS: A case-control study was conducted on 13 patients with VL in comparison with nine controls. The immune response was evaluated using immunohistochemistry, for CD4, CD8, CD68, IL-4, IFN-γ, TNF-α and IL-10. Histological findings from the villi, crypts and inflammatory process were analyzed. RESULTS: All the cases of VL presented Leishmania antigens. No antigen was detected in the control group. The villus size was greater in the VL patients (p < 0.05). CD68 (macrophages) and CD4 levels were higher in the VL patients (p < 0.05). No differences in the expression of CD8, TNF-α, IL-10 or IL-4 were demonstrated. The number of cells expressing IFN-γ was lower in the VL patients (p < 0.05). CONCLUSIONS: Low levels of cytokines were found in the gastrointestinal tract of patients with VL. This pattern was not found in other organs affected by the disease. Immunotolerance of this tissue against Leishmania could explain these findings, as occurs with intestinal bacteria.

INTRODUÇÃO: Leishmaniose visceral (LV) é uma doença tropical negligenciada com uma resposta imune complexa em diferentes órgãos. Este padrão de resposta imune órgão-específica nunca foi avaliada no trato gastrointestinal. O objetivo deste estudo foi determinar a resposta imune in situ em biópsias duodenais de pacientes com LV. MÉTODOS: Um estudo de caso controle com 13 pacientes com LV foi comparado com 9 controles. A resposta imune foi avaliada por imunohistoquímica para CD4, CD8, CD68, IL-4, IFN-γ, TNF-α e IL-10. Achados histológicos nos vilos, criptas e processo inflamatório foram analisados. RESULTADOS: Todos os casos de LV apresentaram antígenos de Leishmania. Nenhum antígeno foi encontrado no grupo controle. O tamanho do vilo foi maior em pacientes com LV (p < 0,05). CD68 (macrófagos) e CD4 estavam aumentados em pacientes com LV (p < 0,05). Nenhuma diferença foi demonstrada na expressão de CD8, TNF-α, IL-10 e IL-4. O número de células expressando IFN-γ foi mais baixo que no grupo controle (p < 0,05). CONCLUSÕES: Baixos níveis de citocinas foram encontrados no trato gastrointestinal de pacientes com LV. Este padrão não foi encontrado em outros órgãos acometidos pela doença. Uma imunotolerância do tecido contra Leishmania poderia explicar estes achados, como ocorre com as bactérias entéricas.

Efeitos da infecção crônica por Toxoplasma gondii sobre a parede intestinal de gatos domésticos / The effects of the infection caused by Toxoplasma gondii on the cat duodenal wall

O objetivo deste trabalho foi analisar os efeitos da infecção causada pelo Toxoplasma gondii sobre a parede do duodeno de gatos. Foram utilizados seis gatos (Felis catus), com cerca de três meses de vida, distribuídos aleatoriamente em Grupo controle (G1; n = 3) e Grupo infectado (G2; n = 3). Os animais do G2 receberam, por via oral, 200 cistos teciduais da cepa ME49 (tipo II) do T. gondii. Apos 40 dias, os animais foram submetidos a eutanásia, laparotomia e retirada do duodeno, que foi fixado em solução de Bouin e submetido a rotina histológica para obtenção de cortes transversais de3 μm. Os cortes foram corados com Hematoxilina-Eosina (HE), Azan, Acido Periódico de Schiff (PAS), Alcian-Blue e Tricrômio de Mallory. Realizou-se uma avaliação qualitativa da parede intestinal e medidas comparativas entre os dois grupos, com relação: à espessura da túnica mucosa, túnica muscular, parede total, altura dos vilos, profundidade das criptas e altura dos enterócitos e seus núcleos. As células caliciformes, os linfócitos intraepiteliais e as células de Paneth foram quantificados. Os resultados mostraram que a infecção levou a atrofia da túnica mucosa, túnica muscular e parede intestinal do duodeno de gatos do G2 (p < 0,05). A altura dos enterócitos apresentou um aumento significativo (p < 0,05) nos animais do G2. Na avaliação qualitativa, as fibras colágenas ocupavam visivelmente uma maior área dos estratos da parede intestinal, o que sugere que estejam aumentadas. Observou-se a redução da secreção de sulfomucinas e o aumento das células de Paneth nesses mesmos animais (p < 0,05).

This paper analyzes the effects of the infection caused by Toxoplasma gondii on the cat duodenal wall. Six cats (Felis catus) with 3-month-old were randomly divided into Control Group (G1; n = 3) and Infected Group (G2; n = 3). The animals from G2 received orarilly 200 T. gondii tissye cysts of ME49-strain (type II). After 40 days, the animals were submitted to euthanasia, laparotomy and had their duodenum removed, fixed in Bouin solution and submitted to histological routine obtaining 3 μm transverse cuts. The cuts were stained with Hematoxylin-Eosin (HE), Azan, Periodic acid – Schiff (PAS), Alcian-Blue, and Mallory trichrome. Qualitative assessment of the intestine wall as well as comparative measurements with respect to the thickness of mucosa, muscle tunic, total wall, the height of the villous, the depth of the crypts, and the height of the enterocytes and their nuclei were carried out. Calciform cells, the intraepithelial lymphocytes, and the Paneth cells were quantified. The results showed that the infection led to the atrophy of the mucosa, muscle tunic, and the intestinal wall of the duodenum of G2 cats (p < 0.05). The enterocytes height presented significant (p < 0.05) increase for G2 animals. According to the qualitative analysis, the collagen fibers were visibly taken a broader area on the intestinal wall layers, what suggests they have increased in size. Decrease in the sulphomucins secretion and the increase of Paneth cells were observed for these animals (p < 0.05).

case of gastric and duodenal strongyloidiasis

Strongyloides stercoralis is a nematode parasite which causes a protracted asymptomatic intestinal infection. It is considered a life threatening condition in immunocompromised patients when hyperinfection is associated with disseminated disease. The diagnosis by routine stool examination is very limited since the larval output in stools is very low. We present the case of a 52 year-old Omani man from Salalah, in the southern region of Oman, with a 15-year history of type 2 diabetes mellitus and recently discovered to have hairy cell leukaemia, who complained of nausea, abdominal pain, loss of appetite and loss of weight. An oesophagogastroduodoscopic biopsy was obtained and histopathologic examination revealed gastrointestinal strongyloidiasis

continuing dilemma of hyperinvasive strongyloidiasis syndrome: a case report and review of literature

A 28-year-old man from Bangladesh was admitted to Al-Jahra Hospital in Kuwait with an Addison's crisis after suddenly stopping steroids prescribed for uveitis. His hospital stay was further complicated by severe gastritis, peritonitis and meningitis. Investigations revealed Strongyloides stercoralis in the sputum, stomach aspirate and duodenal mucosa. The patient died in spite of intensive treatment. The problem of hyperinvasive strongyloidiasis syndrome is reviewed

Arthrostoma miyazakiense (Nematoda: Ancylostomatidae) infection in raccoon dogs of Korea and experimental transmission to dogs

Arthrostoma miyazakiense (Nematoda: Ancylostomatidae) is a hookworm species reported from the small intestines of raccoon dogs (Nyctereutes procyonoides) in Japan. Five Korean raccoon dogs (N. procyonoides koreensis) caught from 2002 to 2005 in Jeollanam-do (Province), a southeastern area of South Korea, contained helminth eggs belonging to 4 genera (roundworm, hookworm, whipworm, and Capillaria spp.) and cysts of Giardia sp. in their feces. Necropsy findings of 1 raccoon dog revealed a large number of adult hookworms in the duodenum. These hookworms were identified as Arthrostoma miyazakiense based on the 10 articulated plates observed in the buccal capsule and the presence of right-sided prevulval papillae. Eggs of A. miyazakiense were 60-65 x 35-40 micrometer (av. 62.5 x 35 micrometer), and were morphologically indistinguishable from those of Ancylostoma caninum. The eggs were cultured to infective 2nd stage larvae via charcoal culture, and 100 infective larvae were used to experimentally infect each of 3 mixed-bred puppies. All puppies harbored hookworm eggs in their feces on the 12th day after infection. This is the first report thus far concerning A. miyazakiense infections in raccoon dogs in Korea, and the first such report outside of Japan.

Expression of cytokines and monosaccharide transporters in the duodenal mucosa of patients with gastrointestinal symptoms in rural Thailand.

Levels of cytokines and GLUT family monosaccharide transporters in the duodenal mucosa were examined in patients from Nong Khai, Thailand, who had underwent gastroscopy because of gastrointestinal problems. Duodenal biopsy specimens were collected from a total of 33 patients (24 males and 9 females, 45.0 +/- 13.5 years old). Ten patients had present or recent intestinal helminth infections, including strongyloidiasis, taeniasis or ascariasis (group A), 7 were urease-test positive, indicating Helicobacter pylori infection (group B), and 16 had neither helminth infections nor urea-test positivity (group C). Total RNA was extracted from the biopsied specimens and a semi-quantitative RT-PCR was performed. The positivities for IL-13, IL-5 and IFN-gamma mRNA expressions in the patients were 24.2, 60.6 and 100%, respectively, with the highest IL-13 and IL-5 positivities in group A, followed by group C and B. The IL-5 positive rate was significantly higher among patients with high peripheral blood eosinophil counts (> 4%) than in patients with low peripheral blood eosinophil counts. GLUT-1 and GLUT-5 were detectable in all the patients. Although GLUT-1 expressions did not differ among groups A, B and C. GLUT-5 expressions were significantly lower in group B than in group C. These results indicate that helminth and H. pylori infections result in different immunopathological responses in the duodenal mucosa, lower expressions of type 2 cytokines and monosaccharide transporters in H. pylori infections than in helminth infections.

Avaliação das alterações imunohistológicas da mucosa do intestino delgado em pacientes portadores da leishmaniose visceral / Evaluation of the immunohistological alterations of the thin intestine mucosa in patients with visceral leishmaniasis

Introdução: A leishmaniose visceral é uma doença que acomete cerca de 500 mil pessoas por ano no mundo e se caracteriza principalmente por um quadro de febre, hepatoesplenomegalia e pancitopenia. Há uma imunossupressão específica frente a Leishmania chagasi. Classicamente esta resposta é modulada pelas células dendríticas, que são as primeiras células que entram em contato com o parasita / Introduction: Visceral leishmaniasis is a disease that strikes around 500 thousand people in the world per year and its major characteristics are fever hepatoesplenomegaly and pancytopenia. There is a specific immunussupression in face of the Leishmania chagasi. Classically this response is modulated by the dendritic cells that are the first cells to get in contact with the parasite...

A human infection of Echinostoma hortense in duodenal bulb diagnosed by endoscopy

As gastroduodenoscopy performed more frequently, case reports of human echinostomiasis are increasing in Korea. A Korean woman presented at a local clinic with complaints of abdominal pain and discomfort that had persisted for 2 weeks. Under gastroduodenoscopy, two motile flukes were found attached on the duodenal bulb, and retrieved with endoscopic forceps. She had history of eating raw frog meat. The two flukes were identified as Echinostoma hortense by egg morphology, 27 collar spines with 4 end-group spines, and surface ultrastructural characters. This report may prove frogs to be a source of human echinostome infections.

Reactive arthritis, psoriasiform lesions and protein loosing enteropathy secondary to Strongyloidiasis.

Reactive arthritis is associated with demonstrable infection at a distant site without evidence of sepsis at the affected joint(s). We present a rare case reactive arthritis where no bacterial or chlamydial infections could be established, rather larvae of Strongyloides stercoralis could be demonstrated in the stool and duodenal biopsy. Reactive arthritis, psoriasiform lesions and malabsorption with hypoproteinaemia, responded to successful treatment with antihelminthic drugs. Early recognition and adequate treatment for gastrointestinal infections and infestations before complications is important.

Manifestaciones digestivas en la fase crónica de la enfermedad de Chagas / Digestive manifestation in chronic phase of Chaga's disease

Se describen dos casos de enfermedad de Chagas en fase crónica, con mega deformaciones del tubo digestivo, ambos casos residentes del municipio de San Martín de Hidalgo, Jalisco. Con una evolución de 12 y 8 años respectivamente; el diagnóstico en ambos fue de acalasia de etiología desconocida. El primer paciente presenta megaesófago, megaduodeno y megaíleon (manifestaciones asociadas poco frecuentes). Los signos y síntomas digestivos fueron: disfagia, dolor retroesternal, regurgitación, sensación de plenitud gástrica, dolor epigástrico, vómito, sialorrea y pérdida de peso. El segundo paciente presenta disfagia, vómito regurgitación, tos de predominio nocturno, sialorrea, hipertrofia de parótidas y pérdida de peso. Los signos y síntomas comunes observadas en ambos casos son: disfagia, vómitos, regurgitación, sialorrea y pérdida de peso. Los signos y síntomas no comunes y asociados al padecimiento son: tos de predominio nocturno, hipertrofia de parótidas, dolor retroesternal, sensación de plenitud gástrica y dolor epigástrico.

Strongyloidiasis in a patient with IgA deficiency.

With rising frequency of immuno suppression particularly due to use of various immuno suppressive agents and increasing incidence of human immuno deficiency virus infection, incidence of opportunistic infection due to various parasites are also on the rise. Persistent strongyloides stercoralis infection which normally also infects healthy individuals is documented in a case of hypogammaglobulinemia reported in the present paper emphasizing it to be another potential opportunistic infection which one may encounter in near future.

Limitaçäo diagnóstica da pesquisa de trofozoítos da Giardia lamblia no aspirado duodenal / Limitations in the diagnosis of Giardia lambia utilizing duodenal secretion

O exame parasitológico de fezes à tradicionalmente considerado um teste com muitos resultados falso negativos no diagnóstico da giardíase. Por outro lasdo, atribui-se elevado poder diagnóstico à pesquisa de trofozoítos no aspirado duodenal. O objetivo desse estudo foi comparar a pesqusia de trofozoítos no líquido duodenal com a eliminaçäo de cistos nas fezes na giardíase assintomática. Foram estudadas 45 crianças com anemia ferropriva com idade entre 1 e 6 anos, 21 com e 24 sem giardíase. Os pacientes realizaram de um a cinco exames parasitológicos de fezes, empregando o métodos de enriquecimento com formol-éter e pesquisa de trofozoítos no líquido duodenal foi positivo em nove (43 por cento) pacientes. Presença de trofozoítos na secreçäo duodenal e ausência de eliminaçäo de cistos nas fezes foram observadas no único paciente que realizou apenas um exame parasitológico de fezes. As 24 crianças sem giardíase realizaram pesquisa de trofozoítos no aspirado duodenal e, pelo menos, três exames parasitológicos de fezes, todos com resultados negativos. Em conclusäo, o exame parasitológico de fezes pelo método de enriquecimento pelo formol-éter apresentou maior positividade do que a pesquisa de trofozoítos no líquido duodenal

Investigación de Giardia lamblia en jugo duodenal obtenido mediante la "cuerda encapsulada" o Enterotest / Giardia lamblia investigation in duodenal juice using the \"string capsule\" or Enterotest

Presentamos nuestra experiencia en la investigación de Giardia lamblia en jugo duodenal obtenido mediante la "cuerda encapsulada" ó Enterotest, realizada en 500 pacientes del Servicio de Gastroenterología del Hospital Nacional "E. Rebagliati M." del IPSS, entre octubre de 1981 a octubre 1984. Fueron hallados 41 pacientes parasitados con Giardia lamblia, dando una incidencia del 8,36%. Este método fué bien tolerado y demostró ser simple, rápido y de gran sensibilidad diagnóstica, permitiendo examinar simultáneamente varios pacientes a muy bajo costo

Some epidemiological studies on ancylostoma duodenal infection

The seasonal incidence of Ancylostoma duodenale infection in Kafr-blolah [Kotor Centre], Gharbia Governorate was high during summer and spring seasons [83.3% and 60% respectively]. The over all incidence of infection was 22.9%. Most of the infected individuals were discharging less than 500 egg per gram stool [10.5% males and 11.9% females] while mild infection was 4.1% males and 4.5% females and severe infection was 6.5% males and 8.1% females. Anaemia was more marked among highly infected individuals discharging more than 2000 eggs/gram stool and the hemoglobin reached 8.7 gram/100 C.C. blood while in mild and low infections, the hemoglobin reached 12.2 and 13.1 gram/100 C.C. blood

Intolerancia a la lactosa y giardiasis. / Lactose intolerance and giardiasis.

Con objeto de estudiar la probable influencia de la Giardiasis en la actividad de la lactosa intestinal, se efectuó el estudio de la curva de tolerancia a la lactosa, en 54 personas portadoras de este parásito, comparándose los métodos, con un grupo control de 28 personas, libres de parasitosis. Se demostró, en el primer grupo, es decir, el portador de giardiasis, cursaron curvas planas de lactosa en 49 casos (90.8% de 54), mientras que el grupo control, este tipo de curva se detectó en 16 personas (57.2% de 28). Estos hallazgos se pudieron correlacionar con la clínica, ya que en el grupo parasitario, solo 4 de ellos (7.5% de 54, toleraban clínicamente la leche. Se considera que la diferencia hallada entre los dos grupos puede ser significativa en la influencia que pudiera tener la guiardiasis en los cuadros de intolerancia a la leche, como una causa secundaria y/u ontogenética.