Urea breath test for Helicobacter pylori infection in adult dyspeptic patients: A meta-analysis of diagnostic test accuracy.

BACKGROUND: Helicobacter pylori (H. pylori) infection has been well-established as a significant risk factor for several gastrointestinal disorders. The urea breath test (UBT) has emerged as a leading non-invasive method for detecting H. pylori. Despite numerous studies confirming its substantial accuracy, the reliability of UBT results is often compromised by inherent limitations. These findings underscore the need for a rigorous statistical synthesis to clarify and reconcile the diagnostic accuracy of the UBT for the diagnosis of H. pylori infection. AIM: To determine and compare the diagnostic accuracy of 13C-UBT and 14C-UBT for H. pylori infection in adult patients with dyspepsia. METHODS: We conducted an independent search of the PubMed/MEDLINE, EMBASE, and Cochrane Central databases until April 2022. Our search included diagnostic accuracy studies that evaluated at least one of the index tests (13C-UBT or 14C-UBT) against a reference standard. We used the QUADAS-2 tool to assess the methodological quality of the studies. We utilized the bivariate random-effects model to calculate sensitivity, specificity, positive and negative test likelihood ratios (LR+ and LR-), as well as the diagnostic odds ratio (DOR), and their 95% confidence intervals. We conducted subgroup analyses based on urea dosing, time after urea administration, and assessment technique. To investigate a possible threshold effect, we conducted Spearman correlation analysis, and we generated summary receiver operating characteristic (SROC) curves to assess heterogeneity. Finally, we visually inspected a funnel plot and used Egger's test to evaluate publication bias. RESULTS: The titles and abstracts of 4621 studies were screened; 79 articles were retrieved and selected for full-text reading. Finally, 60 studies were included in the diagnostic test accuracy meta-analysis. Our analysis demonstrates superior diagnostic accuracy of 13C-UBT over 14C-UBT, indicated by higher sensitivity (96.60% vs 96.15%), specificity (96.93% vs 89.84%), likelihood ratios (LR+ 22.00 vs 10.10; LR- 0.05 vs 0.06), and area under the curve (AUC; 0.979 vs 0.968). Notably, 13C-UBT's DOR (586.47) significantly outperforms 14C-UBT (DOR 226.50), making it the preferred diagnostic tool for dyspeptic individuals with H. pylori infection. Correlation analysis revealed no threshold effect (13C-UBT: r = 0.48; 14C-UBT: r = -0.01), and SROC curves showed consistent accuracy. Both 13C-UBT and 14C-UBT showed high AUC values (13C-UBT 0.979; 14C-UBT 0.968) near 1.00, reinforcing their excellent accuracy and endorsing both as reliable diagnostic tools in clinical practice. CONCLUSION: In summary, our study has demonstrated that 13C-UBT has been found to outperform the 14C-UBT, making it the preferred diagnostic approach. Additionally, our results emphasize the significance of carefully considering urea dosage, assessment timing, and measurement techniques for both tests to enhance diagnostic precision. Nevertheless, it is crucial for researchers and clinicians to evaluate the strengths and limitations of our findings before implementing them in practice.

Selective visuoconstructional impairment following mild COVID-19 with inflammatory and neuroimaging correlation findings.

People recovered from COVID-19 may still present complications including respiratory and neurological sequelae. In other viral infections, cognitive impairment occurs due to brain damage or dysfunction caused by vascular lesions and inflammatory processes. Persistent cognitive impairment compromises daily activities and psychosocial adaptation. Some level of neurological and psychiatric consequences were expected and described in severe cases of COVID-19. However, it is debatable whether neuropsychiatric complications are related to COVID-19 or to unfoldings from a severe infection. Nevertheless, the majority of cases recorded worldwide were mild to moderate self-limited illness in non-hospitalized people. Thus, it is important to understand what are the implications of mild COVID-19, which is the largest and understudied pool of COVID-19 cases. We aimed to investigate adults at least four months after recovering from mild COVID-19, which were assessed by neuropsychological, ocular and neurological tests, immune markers assay, and by structural MRI and 18FDG-PET neuroimaging to shed light on putative brain changes and clinical correlations. In approximately one-quarter of mild-COVID-19 individuals, we detected a specific visuoconstructive deficit, which was associated with changes in molecular and structural brain imaging, and correlated with upregulation of peripheral immune markers. Our findings provide evidence of neuroinflammatory burden causing cognitive deficit, in an already large and growing fraction of the world population. While living with a multitude of mild COVID-19 cases, action is required for a more comprehensive assessment and follow-up of the cognitive impairment, allowing to better understand symptom persistence and the necessity of rehabilitation of the affected individuals.

Increased serum gastrin in patients with different clinical forms of Chagas disease coinfected with Helicobacter pylori.

Trypanosoma cruzi and Helicobacter pylori (HP) are pathogens that cause chronic diseases and have been associated with hypergastrinemia. The aim of this study was to evaluate the fasting gastrin levels in patients with different clinical forms of Chagas disease (CD), coinfected or not by HP. The enrolled individuals were outpatients attending at the university hospital. HP infection was assessed by serology and 13 C-urea breath test. Fasting serum gastrin concentration was measured by chemiluminescence assay. Gastric endoscopic and histological features were also evaluated. Associations between CD and serum gastrin level were evaluated in a logistical model, adjusting for age, gender and HP status. A total of 113 patients were evaluated (45 with Chagas disease and 68 controls). In the multivariate analysis, increasing serum gastrin levels (OR= 1.02; 95% CI= 1.01-1.12), increasing age (OR= 1.05; 95% CI= 1.02 - 1.09) and HP-positive status (OR = 2.88; 95% CI = 1.10 - 7.51) remained independently associated with CD. The serum gastrin levels were significantly higher in the group of patients with the cardiodigestive form ( P = 0.03) as well as with digestive form ( P = <0.001) of Chagas disease than in the controls. In conclusion, patients with cardiodigestive and digestive clinical forms of CD have increased basal serum gastrin levels in comparison with controls. Moreover, we also demonstrated that H. pylori coinfection contributes to the hypergastrinemia shown in CD.

Histological and endoscopic features of the stomachs of patients with Chagas disease in the era of Helicobacter pylori

Introduction Most studies that have evaluated the stomachs of patients with Chagas disease were performed before the discovery of Helicobacter pylori and used no control groups. This study compared the gastric features of chagasic and non-chagasic patients and assessed whether gastritis could be associated with Chagas disease. Methods Gastric biopsy samples were taken from patients who underwent endoscopy for histological analysis according to the Updated Sydney System. H. pylori infection was assessed by histology, 16S ribosomal ribonucleic acid (rRNA) polymerase chain reaction (PCR), serology and the 13C-urea breath test. Patients were considered H. pylori-negative when all of these diagnostic tests were negative. Clinical and socio-demographic data were obtained by reviewing medical records and using a questionnaire. Results The prevalence of H. pylori infection (70.3% versus 71.7%) and chronic gastritis (92.2% versus 85%) was similar in the chagasic and non-chagasic groups, respectively; such as peptic ulcer, atrophy and intestinal metaplasia. Gastritis was associated with H. pylori infection independent of Chagas disease in a log-binomial regression model. However, the chagasic H. pylori-negative patients showed a significantly higher grade of mononuclear (in the corpus) and polymorphonuclear ...

Th1 immune response to H. pylori infection varies according to the age of the patients and influences the gastric inflammatory patterns.

To compare children and adults in respect to the effect of H. pylori infection on the gastric concentrations of cytokines linked to innate and Th1 immune response, as well as to investigate the changes in the gastric concentrations of the studied cytokines according to the age. We studied 245 children (142 H. pylori-negative and 103 H. pylori-positive) and 140 adults (40 H. pylori-negative and 100 H. pylori-positive). The gastric concentrations of cytokines representative of the innate and Th1 response were higher in the H. pylori-positive than in the -negative children and adults. The gastric concentrations of IL-1α and TNF-α were significantly higher, while those of IL-2, IL-12p70 and IFN-γ were lower in the infected children than in the infected adults. In the infected children, the gastric concentration of IL-1α, IL-2, IL-12p70 and IFN-γ increased, whereas in adults, the gastric concentrations of IFN-γ and IL-12p70 decreased with the aging. Increased gastric concentration of Th1 associated cytokines correlated with increased degree of gastritis that is the background lesion for the development of the H. pylori associated severe diseases. Concluding, Th1 response to H. pylori infection varies according to the age and seems to have determinant implication in the H. pylori infection outcomes.

Histological and endoscopic features of the stomachs of patients with Chagas disease in the era of Helicobacter pylori.

INTRODUCTION: Most studies that have evaluated the stomachs of patients with Chagas disease were performed before the discovery of Helicobacter pylori and used no control groups. This study compared the gastric features of chagasic and non-chagasic patients and assessed whether gastritis could be associated with Chagas disease. METHODS: Gastric biopsy samples were taken from patients who underwent endoscopy for histological analysis according to the Updated Sydney System. H. pylori infection was assessed by histology, 16S ribosomal ribonucleic acid (rRNA) polymerase chain reaction (PCR), serology and the 13C-urea breath test. Patients were considered H. pylori-negative when all of these diagnostic tests were negative. Clinical and socio-demographic data were obtained by reviewing medical records and using a questionnaire. RESULTS: The prevalence of H. pylori infection (70.3% versus 71.7%) and chronic gastritis (92.2% versus 85%) was similar in the chagasic and non-chagasic groups, respectively; such as peptic ulcer, atrophy and intestinal metaplasia. Gastritis was associated with H. pylori infection independent of Chagas disease in a log-binomial regression model. However, the chagasic H. pylori-negative patients showed a significantly higher grade of mononuclear (in the corpus) and polymorphonuclear (PMN) (in the antrum) cell infiltration. Additionally, the patients with the digestive form of Chagas disease showed a significantly lower prevalence of corpus atrophy than those with other clinical forms. CONCLUSIONS: The prevalence of H. pylori infection and of gastric histological and endoscopic features was similar among the chagasic and non-chagasic patients. Additionally, this is the first controlled study to demonstrate that H. pylori is the major cause of gastritis in patients with Chagas disease.

Seroprevalence of Helicobacter pylori infection in chagasic and nonchagasic patients from the same geographical region of Brazil.

INTRODUCTION: In this study, we evaluated the seroprevalence of Helicobacter pylori infection among chagasic and non-chagasic subjects as well as among the subgroups of chagasic patients with the indeterminate, cardiac, digestive, and cardiodigestive clinical forms. METHODS: The evaluated subjects were from the Triângulo Mineiro region, Minas Gerais, Brazil. Chagasic patients showed positive reactions to the conventional serological tests used and were classified according to the clinical form of their disease. Immunoglobulin G antibodies specific to H. pylori were measured using a commercial enzyme-linked immunosorbent assay kit. RESULTS: The overall H. pylori prevalence was 77.1% (239/310) in chagasic and 69.1% (168/243) in non-chagasic patients. This difference was statistically significant even after adjustment for age and sex (odds ratio = 1.57; 95% confidence interval, 1.02-2.42; p = 0.04) in multivariate analysis. The prevalence of infection increased with age in the non-chagasic group (p = 0.007, χ² for trend), but not in the chagasic group (p = 0.15, χ² for trend). H. pylori infection was not associated with digestive or other clinical forms of Chagas disease (p = 0.27). CONCLUSIONS: Our findings demonstrate that chagasic patients have a higher prevalence of H. pylori compared to non-chagasic subjects; a similar prevalence was found among the diverse clinical forms of the disease. The factors contributing to the frequent co-infection with H. pylori and Trypanosoma cruzi as well as its effects on the clinical outcome deserve further study.

Seroprevalence of Helicobacter pylori infection in chagasic and nonchagasic patients from the same geographical region of Brazil / Soroprevalência da infecção por Helicobacter pylori em indivíduos chagásicos e não-chagásicos da mesma região geográfica do Brasil

INTRODUCTION: In this study, we evaluated the seroprevalence of Helicobacter pylori infection among chagasic and non-chagasic subjects as well as among the subgroups of chagasic patients with the indeterminate, cardiac, digestive, and cardiodigestive clinical forms. METHODS: The evaluated subjects were from the Triângulo Mineiro region, Minas Gerais, Brazil. Chagasic patients showed positive reactions to the conventional serological tests used and were classified according to the clinical form of their disease. Immunoglobulin G antibodies specific to H. pylori were measured using a commercial enzyme-linked immunosorbent assay kit. RESULTS: The overall H. pylori prevalence was 77.1% (239/310) in chagasic and 69.1% (168/243) in non-chagasic patients. This difference was statistically significant even after adjustment for age and sex (odds ratio = 1.57; 95% confidence interval, 1.02-2.42; p = 0.04) in multivariate analysis. The prevalence of infection increased with age in the non-chagasic group (p = 0.007, χ2 for trend), but not in the chagasic group (p = 0.15, χ2 for trend). H. pylori infection was not associated with digestive or other clinical forms of Chagas disease (p = 0.27). CONCLUSIONS: Our findings demonstrate that chagasic patients have a higher prevalence of H. pylori compared to non-chagasic subjects; a similar prevalence was found among the diverse clinical forms of the disease. The factors contributing to the frequent co-infection with H. pylori and Trypanosoma cruzi as well as its effects on the clinical outcome deserve further study.

INTRODUÇÃO: No presente estudo, foi comparada a soroprevalência da infecção por Helicobacter pylori entre os indivíduos chagásicos e não-chagásicos, bem como entre subgrupos de chagásicos com as formas clínicas indeterminada, cardíaca, digestiva e cardiodigestiva. MÉTODOS: Os indivíduos avaliados eram provenientes da região do Triângulo Mineiro, Minas Gerais, Brasil. Foram realizados testes sorológicos convencionais para diagnóstico da infecção pelo T. cruzi e os chagásicos foram classificados de acordo com a forma clínica. O diagnóstico de infecção por H. pylori foi estabelecido pela detecção de anticorpos IgG específicos utilizando-se um kit comercial de ELISA. RESULTADOS: A prevalência da infecção por H. pylorifoi 77,1% (239/310) no grupo de pacientes chagásicos e 69,1% (168/243) no grupo de não-chagásicos. Esta diferença foi estatisticamente significativa mesmo após ajuste para idade e sexo (OR = 1,57; 95% CI, 1,02-2,42; p = 0,04) na análise multivariada. A prevalência da infecção aumentou de acordo com a idade no grupo não-chagásicos (p = 0,007, χ2 for trend) mas este aumento não foi observado no grupo dos chagásicos (p = 0,15, χ2 for trend). Não houve associação da infecção por H. pylori com a forma digestiva ou com qualquer outra forma clínica da doença de Chagas (p = 0,27). CONCLUSÕES: Foi demonstrado que pacientes chagásicos apresentam maior prevalência da infecção por H. pylori quando comparados com não-chagásicos, independente da forma clínica da doença. Os fatores que contribuem para a frequente co-infecção Helicobacter pylori e Trypanosoma cruzi, bem como seus efeitos na evolução clínica das doenças associadas devem ser melhor estudados.

Helicobacter pylori virulence factors as tools to study human migrations.

Helicobacter pylori is one of the most common infections worldwide. In most individuals it consists in a lifelong host-pathogen relationship without consequences, but in some subjects it is associated with peptic ulcer disease and gastric cancer. Polymorphism in genes that code bacterial virulence factors, cagA and vacA, are independently associated with the infection severe outcomes and are geographically diverse. In the last decade, accumulated knowledge allowed to characterize typical H. pylori strain patterns for all the major human populations; patterns that can be used to study the origin of specific human groups. Thus, the presence or absence of cagA, cagA EPIYA genotypes, and vacA subtypes can be used as tools to study not only the geographic origin of specific human populations, but also to identify markers of historical contact between different ethnicities. We report here a study including a set of native Amazon Amerindians that had supposedly been some, but little, contact with European Brazilian colonizer and/or African slaves. They harbor H. pylori strains in a mixed pattern with Asian and Iberian Peninsula characteristics. It is possible that this finding represents H. pylori recombination upon short contact between human groups. Alternatively, it could be due to a founder effect from a small cluster of Asian origin native Americans.

Bacterial colonization of the ileum in rats with obstructive jaundice

Qualitative and quantitative alterations in ileal flora during obstructive jaundice and the role of bile salts were evaluated in rats. Obstructive jaundice was associated with bacterial overgrowth in the ileum. This effect may be due to the reduced concentration of bile salts, since dietary supplementation reduced the small bowel aerobic bacterial flora.

As alterações qualitativas e quantitativas da flora ileal na obstrução biliar e o papel dos sais biliares foram avaliados em ratos. Em animais com obstrução biliar houve aumento da população ileal. Esse efeito é provavelmente causado pela ausência de sais biliares no lúmen ileal, uma vez que em animais cuja dieta foi suplementada com sais biliares houve redução da flora ileal.

Características da gastrite crônica associada a Helicobacter pylori: aspectos topográficos, doenças associadas e correlação com o status cagA / Helicobacter pylori associated gastritis: topographical pattern, associated diseases and correlation with cagA status

OBJETIVOS: Analisar o padrão topográfico da gastrite por H. pylori em relação ao status cagA e associação com úlcera duodenal (UD) e carcinoma gástrico precoce (CaGp). MATERIAL E MÉTODO: Estudamos prospectivamente 160 biopsias endoscópicas e 40 peças de gastrectomia por CaGp. Amostras do antro e do corpo na pequena e grande curvaturas, da incisura e do tumor, foram processadas rotineiramente para histologia com histoquímica para caracterização da metaplasia intestinal (MI). O Helicobacter pylori foi avaliado por histologia, imuno-histoquímica, cultura e reação em cadeia de polimerase (PCR) e o status cagA por PCR. A gastrite crônica (GC) foi classificada segundo o sistema Sydney. Realizou-se estudo topográfico em 130 pacientes, analisando os parâmetros de gastrite comparativamente entre as áreas e em relação ao status cagA. RESULTADOS: Cento e vinte e um pacientes apresentaram GC, 24 UD e 14 eram normais. Detectaram-se amostras cagA-positivas em 59 pacientes com GC, 17 com UD e 24 com CaGp. Todos os parâmetros de GC foram significativamente mais intensos nos pacientes infectados por amostras cagA-positivas, que se associavam ainda à presença de atrofia e MI. A MI foi significativamente mais intensa na porção média da pequena curvatura antral do que nas demais regiões. Nos pacientes com GC e CaGp, infectados por amostras cagA-positivas, inflamação e atividade acometiam igualmente o antro e corpo distal, enquanto a atrofia e a MI predominavam no antro, particularmente na pequena curvatura do antro médio. Nos pacientes cagA-negativos a GC era predominantemente antral, e na UD a GC apresentava predominância antral, independentemente do status cagA. CONCLUSÕES: Nossos dados sugerem que o padrão de gastrite por H. pylori se relaciona com fatores de virulência da bactéria. As lesões pré-neoplásicas são significativamente mais intensas na pequena curvatura do antro médio, onde surge a maioria dos carcinomas gástricos (CaG).

Associaçäo entre cagA e alelos do vacA de Helicobacter pylori e úlcera duodenal em crianças no Brasil / VacA alleles, cagA, and duodenal ulcer in children in Brazil

Helicobacter pylory é o principal agente de gastrite em seres humanos e fator de risco para úlcera péptica e câncer gástrico. A evoluçäo da infecçäo está relacionada a diversos fatores, inclusive bacterianos, como presença de cagA e genótipo s1ðm1 do vacA, associados com o desenvolvimento de úlcera e adenocarcinoma gástrico. O objetivo deste estudo foi investigar a associaçäo entre cagA e alelos do vacA em H. pylori isolado de crianças e relacionar os achados com a doença apresentada pelo paciente. Foram estudadas 65 crianças (24 com úlcera duodenal e 41 sem úlcera gástrica ou duodenal). A pesquisa de cagA e de alelos do vacA foi feita por PCR em amostras da bactéria isoladas do estômago dos pacientes. Infecçäo mista foi identificada em dez (15,4 por cento) crianças. Entre os pacientes com monoinfecçäo, o alelo s1 foi detectado em amostras isoladas de 40 (72,7 por cento), e o m1 em 34 (61,8 por cento). CagA foi identificado em H. pylori isolado de 38 (69,1 por cento) pacientes. Foi observada associaçäo entre presença de cagA de genótipo s1ðm1 (p = 10ð7) e entre cagA e padräo s1ðm1 com úlcera duodenal (p = 0,073 e p = 0,037, respectivamente). Em conclusäo, infecçäo mista por H. pylori é comum em crianças brasileiras, e amostras da bactéria apresentando o alelo s1 e cagA säo as mais prevalentes no nosso meio. A concomitância do alelo s1 do vacA e de cagA foi freqüentemente observada, e a associaçäo de amostras positivas de s1 e de cagA com úlcera duodenal foi confirmada neste trabalho

Prevalence of Helicobacter pylori infection in a rural area of the State of Mato Grosso, Brazil

The prevalence of Helicobacter pylori infection was evaluated by ELISA in 40 children and teenagers and in 164 adults from a rural area of the State of Mato Grosso, Brazil. Antibodies to H. pylori were detected in the serum of 31 (77.5 per cent) children and teenagers and in 139 (84.7 per cent) adults. The prevalence of infection increased with age (x² for trend, p<0.01) even though no variation occurred in the region in the present century in terms of living conditions or sanitation, economical development and migratory influx supporting the hypothesis that the infection is also acquired during later life in developing countries. An inverse correlation was observed between the prevalence of infection and annual family income (x² for trend, p<0.013). There was no correlation between type of system for sewage disposal and prevalence of infection (p=0.08). In conclusion, the prevalence of H. pylori infection in Nossa Senhora do Livramento, a rural area from Brazil, is very high and similar to that observed in other developing countries. Furthermore, the increase in the prevalence of infection with age observed in this population seems to be due to both, cohort effect and acquisition of the infection during later life.

Furazolidona x cimetidine em pacientes portadores de úlcera duodenal ativa e Helicobacter pylori no antro gástrico / Furazolidone and cimetidine in patients with active duodenal ulcer and Helicobacter pylori in the gastric antrum

Para se avaliar o efeito da furazolidona na doença ulcerosa e na erradicaçäo do Helicobacter pylori (Hp) foi realizado um ensaio terapêutico comparando-a com a cimetidina. O delinemento do estudo foi prospectivo, duplo-cego, duplo-placebo e randomizado, envolvendo 31 pacientes com úlcera duodenal ativa de Hp no antro gástrico. Avaliaçöes clínica, endoscópica, bacteriológica e histológica foram feitas antes e após 4 semanas de tratamento. Naqueles pacientes que näo cicatrizaram suas úlceras nas primeiras 4 semanas, o tratamento foi continuado por mais 4 semanas, quando novo exame endoscópico com biopsia era realizado. Foi observado que a furazolidona, quando comparada à cimetidina, mostrou-se mais eficaz na erradicaçäo do Hp, tnato logo após o tratamento (27% x 0%), quanto após 6 meses (18% x 0%), cicatriza a úlcera péptica duodenal (91% x 87%), e reduz significativamente (p < 0,025) a recidiva da úlcera (30% x 92%), 6 meses após tratamento

Estudo bacteriológico semi-quantitativo de pontas e catéteres endovenosos

Setenta e seis catéteres endovenosos retirados de setenta e seis pacientes internados no Hospital das Clínicas/UFMG foram cultivados, empregando-se técnicas semi-quantitativas. Vinte e seis deles exibiram um crescimento igual ou superior a 15 colônias por placa (34,21%). Neste grupo, Klebsiella pneumoniae foi o microrganismo mais freqüentemente isolado (23,33%). No grupo de catéteres com crescimento entre 1 e 14 colônias por placa predominou o Staphylococcus epidermidis (50,00%). Seis pacientes com cultura de catéter positiva apresentaram também hemoculturas positivas, tendo sido isolados nestes casos, os mesmos microrganismos do sangue e do catéter. Nenhum catéter com crescimento de 1 a 14 colônias por placa associou-se à bacteremia (P < 0,001). Foram ainda executados testes de suscetibilidade a antimicrobianos das amostras isoladas

Participaçäo de rotavírus e adenovírus na diarréia aguda da infância, em Belo Horizonte / Participation of rotavirus and adenovirus in acute diarrhoea of childhood, in Belo Horizonte

Rotavírus e adenovírus foram pesquisados nas fezes de 152 crianças com diarréia aguda, de até 5 anos de idade, em Belo Horizonte, no período de 1981 a 1985. Os espécimes foram diluídos em soluçäo tamponada e centrifugados. Os sobrenadantes foram usados para a detecçäo do vírus, empregando-se o método imunoenzimático (EIARA). A pesquisa do Rotavírus foi positiva em 32 crianças (21,05%) e de Adenovírus em 7 (4,60%) tendo sido identificados 2 vírus, simultaneamente, em 3 pacientes. Através de eletroforese em gel de poliacrilamida identifiocou-se, nas fezes de um paciente com 3 meses de idade, uma amostra de Rotavírus com perfil do grupo C

Valor do exame de esfregaço de fezes corado pelo método de Gram modificado no diagnóstico da enterite causada pelo Campylobacter jejuni / The value of a modified Gram staining of feces smears for diagnosis of Campylobacter jejuni enteritis

Foram estudadas 128 crianças (98 com diarréia aguda e 30 sem diarréia), de até dois anos de idade, que näo se encontravam em uso de drogas antimicrobianas, no período de agosto/82 a janeiro/84, em Belo Horizonte, MG, com o objetivo de se pesquisar o valor do exame do esfregaço de fezes, corado pelo método de Gram Modificado como proposto por Sazie & Titus, no diagnóstico da enterite causada pelo Campylobacter jejuni. Foram pesquisados microrganismos corados em vermelho pela carbolfucsina, curvos, em forma de "S" ou espiralados e os resultados obtidos foram comparados com os da cultura das fezes em meio de Butzler modificado. Foram visualizados microorganismos com morfologia sugestiva de Campylobacter jejuni em 14 pacientes com diarréia aguda (14,3%). Neste grupo, esta bactéria foi isolada em 10 pacientes. Apenas um paciente apresentou cultura negativa e exame direto positivo. Näo foram visualizados microrganismoss com morfologia sugestiva de Campylobacter jejuni nas amostras de fezes de crianças sem diarréia. A especificidade, sensibilidade e valor preditivo do Gram modificado foi de 95,4%, 90,9% e 71,4% respectivamente. Portanto, este método parece ser de grande valor no diagnóstico da diarréia aguda causada pelo Campylobacter jejuni, especialmente no nosso meio onde grande parte dos laboratórios de bacteriologia säo dotados de poucos recursos, pois trata-se de um método diagnóstico rápido, de fácil execuçäo e de baixo custo, devendo ser particularmente recomendado em pacientes com doença severa, nos quais o tratamento específico com antibacterianos pode ser necessário

Intoxicaçäo alimentar pelo Clostridium perpringens / Clostridium perfringens food poisoning

A intoxicaçäo alimentar causada pelo Clostridium perfringens resulta da ingestäo de alimento contaminado com aproximadamente 10**6 a 10**7 formas vegetativas do microrganismo=g, subseqüente multiplicaçäo e esporulaçäo das formas vegetativas no lúmen do intestino delgado e produçäo e liberaçäo de enterotoxina que induz a passagem de líquido dos capilares sanguíneos para dentro da luz intestinal causando diarréia

Colite pseudomembranosa pelo Clostridium difficile / Pseudomembranous colitis by Clostridium difficile

O Clostridium difficile é atualmente responsabilizado pela maioria dos casos de colite pseudomembranosa relacionada com terapia antimicrobiana. Os sinais apresentados pelos pacientes variam desde um quadro de diarréia moderada a uma colite fulminante. Em pacientes adultos com suspeita clínica de colite pseudomembranosa, a demonstraçäo da citotoxina do microrganismo das fezes, associada à boa resposta terapêutica com o uso de vancomicina é diagnóstico. A abordagem terapêutica inclui a remoçäo da droga antibacteriana, reposiçäo hidroeletrolitica, bem como a administraçäo da vancomicina, quando um tratamento específico é necessário

Diagnóstico presuntivo de Escherichia coli enterotoxigênica através de provas de hemoaglutinaçäo / Presumptive diagnosis of enterotoxigenic Escherichia coli by hemagglutination tests

Foram realizadas provas de hemoaglutinaçäo empregando-se hemácias bovinas e humanas, com o objetivo de se comparar os padröes de hemoaglutinaçäo apresentados por amostras de Escherichia coli enterotoxigênicas e enteropatogênicas clássicas e näo enteropatogênicas e averiguar se este procedimento poderia ser empregado para uma demonstraçäo presuntiva de amostras enterotoxigênicas. A análise estatística, através do teste do X2 (p <0,01), evidenciou diferenças significativas entre os padröes de hemoaglutinaçäo exibidos pelas amostras enterotoxigênicas e amostras näo produtoras de enterotoxinas. Este resultado, acrescido do fato de que o método é simples, rápido e barato recomenda o seu emprego no diagnóstico presuntivo de Escherichia coli enterotoxigênica, pois, a pesquisa de enterotoxinas é um procedimento praticamente impossível de ser realizado, rotineiramente, por laboratórios de diagnóstico