Helicobacter pylori transiently in the mouth may participate in the transmission of infection

Helicobacter pylori infection is associated with peptic ulcer and gastric carcinoma. The oral cavity may be a reservoir for H. pylori; however, the results of studies on this subject are controversial. We employed single-step and nested polymerase chain reactions (PCR) to detect the presence of the vacA, ureA and 16S rDNA genes of H. pylori in the stomach, saliva and dental plaque of 30 subjects. The results were confirmed by sequencing. Nested 16S rDNA and ureA amplification was achieved in 80 percent of gastric, 30 percent of saliva and 20 percent of dental plaque specimens. Sequencing of 10, seven and four 16S rDNA products from stomach, saliva and dental plaque, respectively, showed > 99 percent identity with H. pylori. Sequencing of the other four oral cavity PCR products showed similarity with Campylobacter and Wolinella species. Additionally, the vacA genotype identified in the samples of different sites was the same within a given subject.H. pylori may be found in the oral cavity of patients with gastric infection, thus it could be a source of transmission. However, results obtained with detection methods based only on PCR should be interpreted with caution because other microorganisms that are phylogenetically very close to H. pylori are also present in the mouth.

Úlcera péptica gastroduodenal e infecção pelo Helicobacter pylori na criança e adolescente / Gastroduodenal peptic ulcer and Helicobacter pylori infection in children and adolescents

OBJETIVO: Apresentar aspectos relevantes relativos à úlcera péptica gastroduodenal e à infecção pelo Helicobacter pylori na criança e adolescente. FONTES DOS DADOS : Livros técnicos e bases de dados MEDLINE e LILACS de 1966 a 2006. SíNTESE DOS DADOS : A úlcera péptica na criança e adolescente pode ser primária, associada à infecção pelo H. pylori, ou secundária, na qual os mecanismos etiopatogênicos dependem da doença de base. A infecção é adquirida predominantemente na infância, com taxas de prevalência que variam de 56,8 a 83,1 por cento nas crianças que vivem nas regiões mais pobres do Brasil e de aproximadamente 10 por cento nas crianças abaixo de 10 anos de idade nos países desenvolvidos. A infecção pode ser diagnosticada por métodos invasivos, que investigam a presença da bactéria, ou de DNA, RNA ou produtos bacterianos em fragmentos de biópsia da mucosa gástrica obtida à endoscopia; também pode ser diagnosticada através de métodos não-invasivos, que compreendem a pesquisa de anticorpos anti-H. pylori em amostras de soro, urina ou saliva, a pesquisa de antígenos da bactéria nas fezes e o teste respiratório com uréia marcada com carbono-13. O método de escolha para o diagnóstico da úlcera péptica é a endoscopia digestiva alta, com a vantagem adicional de, durante o procedimento, permitir a obtenção de fragmentos de mucosa gástrica para o diagnóstico da infecção e estudo histopatológico. CONCLUSÕES: A infecção por H. pylori é a principal causa de úlcera péptica na infância. A erradicação da bactéria com antimicrobiano é acompanhada de cura da doença, sendo, portanto, indicada em todas as crianças H. pylori-positivas com úlcera péptica em atividade, recorrente, cicatrizada ou complicada.

OBJECTIVE: To show important aspects of gastroduodenal peptic ulcer and of Helicobacter pylori infection in children and adolescents. SOURCES: Technical textbooks and MEDLINE and LILACS databases including publications between 1966 and 2006. SUMMARY OF THE FINDINGS : The etiology of peptic ulcer in children and adolescents may be primary, associated with H. pylori infection, or secondary, in which etiopathogenic mechanisms rely upon the underlying disease. The infection is acquired predominantly in childhood, with prevalence rates between 56.8 and 83.1 percent in children who live in the poorest Brazilian regions, amounting to nearly 10 percent in children aged less than 10 years in industrialized countries. The infection can be diagnosed by invasive methods, which investigate the presence of the bacterium, or of DNA, RNA or bacterial products in biopsy fragments of the gastric mucosa obtained at endoscopic examination; it can also be diagnosed through noninvasive methods, which include the detection of anti-H. pylori antibodies in serum, urine or saliva samples, detection of bacterial antigens in stool samples, and the carbon 13-labeled urea breath test. However, upper gastrointestinal endoscopy is the method of choice for the diagnosis of peptic ulcer, as it allows collecting fragments from the gastric mucosa during the procedure for the diagnosis of infection and for histopathological analysis. CONCLUSIONS: H. pylori infection is the major cause of peptic ulcer among children. Eradication of the bacterium with antimicrobial therapy results in the cure of the disease, and is therefore indicated for all children with H. pylori infection with an active, recurrent, healed, or complicated peptic ulcer.

Helicobacter pylori infection in adults from a poor urban community in northeastern Brazil: demographic, lifestyle and environmental factors

We investigated the prevalence and the risk factors for infection with Helicobacter pylori in a randomly-selected population of adults from a low-income community in Northeastern Brazil. Helicobacter pylori infection was determined by ELISA. Risk factors were assessed using a structured interview. Two hundred and four individuals were included in the study, including 49 males and 155 females, ranging from 18 to 80 years old. Overall, 165 of 204 participants (80 percent) were H. pylori positive, without significant gender differences (p= 0.49). The infection rate was of 84.7 percent in subjects 18 to 30 years of age, increasing to 92 percent in subjects 46-60 years old. Above 60 years old, the prevalence decreased slightly. As a whole, the prevalence of infection did not increase significantly (p=0.147) with age. There were no significant differences in the prevalence of H. pylori infection, when patients were classified by age, smoking habit, educational level, alcohol consumption, the number of persons per room, the number of children per household, the number of adults per household, cup-sharing, household pets, toilet location, number of persons per bed and medical history of antibiotic and raw vegetable ingestion. In conclusion, no risk factors associated with infection was found in these adults, suggesting that the infection, even in a poor population, may be acquired predominantly during childhood; the relatively high prevalence that we observed may be more due to a cohort effect than to acquisition of infection during adulthood.

Prevalence of Helicobacter pylori infection in Fortaleza, Northeastern Brazil

A prevalência da infecção pelo Helicobacter pylori foi avaliada em amostra randomizada de indivíduos de uma comunidade urbana de baixa renda em Fortaleza, Estado do Ceará. O H. pylori foi detectado em 384 (62.9 por cento) dos 610 participantes. A taxa de infecção foi de 47.5 por cento em indivíduos com seis meses a 10 anos de idade, aumentou para 73.3 por cento entre indivíduos com 11 a 20 anos, e continuou a aumentar com a idade, atingindo 87 por cento naqueles com aproximadamente 60 anos. Após essa idade, a prevalência diminuiu discretamente. A prevalência da infecção aumentou significantemente com a idade (p<0.0001).

Immunoblotting for the serodiagnosis of Helicobacter pylori áinfection in Brazilian patients with and without gastric carcinoma

We evaluated the performance of a commercial immunoblotting in the serodiagnosis of Helicobacter pylori infection in Brazilian patients. The presence of anti-H. pylori antibodies was also investigated in a group of 20 duodenal ulcer patients after successful treatment. One hundred and ninety one patients were studied. Among the 164 infected patients, 46 had gastric carcinoma. The duodenal ulcer patients were treated with antimicrobial drugs and the eradication of the microorganism was confirmed in all of them one month after the end of the treatment by the 13C-urea breath test. Sera were assayed for H. pylori antibodies using the Helicoblot 2.0 (Genelabs Diagnostics, Singapore). The sensitivity, specificity, positive, and negative predictive values of the test were 93.9 percent, 92.6 percent, 98.7 percent, and 71.4 percent, respectively. The sensitivity of the test was similar in patients with (93.5 percent) and without (95.7 percent) gastric carcinoma. Twenty-four months after the end of the treatment, the band of 116 kDa was still detected in one of the patients. In conclusion, the Helicoblot 2.0 is an accurate test to diagnose H. pylori infection and although it can not be employed to monitor the bacterium eradication, it may be useful for diagnosing past infection, especially in gastric carcinoma patients.

Chicken carcasses as a source of Campylobacter jejuni in Belo Horizonte, Brazil

C. jejuni foi pesquisado em carcaças de frango prontas para consumo e em fezes de magatrial, tendo sido isolado em 19 (38,0%) dentre 50 carcaças e em 2 (13,3%) dentre 15 amostras de fezes provenientes dos abatedouros näo industriais e em 1(2,0%) dentre 50 carcaças do abatedouro industrializado. Neste último, o microrganismo näo foi isolado de nenhuma das 40 amostras de fezes examinadas. O perfil eletroforético em gel de poliacrilamida, as características bioquímicas e o padräo de susceptibilidade aos isolados das carcaças foram muito semelhantes aos das amostras isoladas das fezes de magarefes, o que sugere que as galinhas podem ser a fonte de C. jejuni para os magarefes e que ambos podem estar envolvidos na transmissäo do microorganismo