Abstract Functional dyspepsia and lactose intolerance (adult-type hypolactasia, ATH) are common conditions that may coexist or even be confounded. Their clinical presentation can be similar, however, lactose intolerance does not form part of the diagnostic investigation of functional dyspepsia. Studies on the association between functional dyspepsia and ATH are scarce. This study aimed to evaluate whether ATH is associated with symptoms of functional dyspepsia. Patients fulfilling the Rome III diagnostic criteria for functional dyspepsia underwent genetic testing for ATH. Dyspeptic symptoms were evaluated and scored according to a validated questionnaire. The diagnostic criteria for ATH was a CC genotype for the -13910C/T polymorphism, located upstream of the lactase gene. The mean scores for dyspeptic symptoms were compared between patients with ATH and those with lactase persistence. A total of 197 functional dyspeptic patients were included in the study. Mean age was 47.7 years and 82.7% patients were women. Eighty-eight patients (44.7%) had a diagnosis of ATH. Abdominal bloating scores were higher in ATH patients compared to the lactase persistent patients (P=0.014). The remaining dyspeptic symptom scores were not significantly different between the two groups. The study results demonstrate an association between ATH and bloating in patients with functional dyspepsia.

RESUMO Contexto Recentemente, uma grande variedade de estudos tem investigado e até mesmo sugerido a presença de Helicobacter pylori como um importante fator no desenvolvimento de eventos restritos ou não ao trato gastrointestinal. A relação já bem estabelecida entre virulência bacteriana e risco aumentado para úlcera péptica ou adenocarcinoma gástrico não parece estar tão elucidada quando se comparam alterações de marcadores inflamatórios, como a proteína C-reativa, com a presença do patógeno. Objetivo O objetivo deste estudo foi avaliar a presença da infecção por H. pylori, a virulência bacteriana e os níveis séricos de proteína C-reativa em indivíduos diagnosticados com dispepsia funcional. Métodos Foram incluídos neste estudo, prospectivamente, 489 indivíduos dispépticos. Os pacientes deveriam preencher os critérios clínicos de Roma III para o diagnóstico de dispepsia funcional sem apresentar doença orgânica evidenciada a partir da endoscopia. A infecção bacteriana foi estabelecida por histologia e pelo teste rápido da urease. Os níveis de proteína C-reativa foram quantificados através de imunonefelometria e o status para a presença da CagA dos indivíduos infectados por H. pylorifoi determinado por ensaio imunoenzimático. Resultados A taxa de prevalência de H. pylori foi de 66.3% e o fator de virulência CagA foi detectado em aproximandamente 43% das amostras positivas. Adicionalmente, denotou-se uma associação entre o consumo deIlex paraguariensis (chimarrão) e a prevalência do patógeno. Um importante efeito da infecção bacteriana na inflamação apenas foi observado localmente, no epitélio gástrico. Conclusão Não foi evidenciada resposta sistêmica ao patógeno aferido através dos níveis de proteína C-reativa, independentemente do status para CagA. Por outro lado, o consumo de chimarrão pode ser sugerido como um fator cultural possivelmente relacionado à transmissão de H. pylori.

ABSTRACT Background Recently, a great variety of studies aimed to investigate and even suggestHelicobacter pylori as an important key factor in gastrointestinal and non-gastrointestinal events development. The well-established relationship between bacterial virulence and increased risk for peptic ulcer or gastric carcinoma is not so clear when comparing inflammation markers alterations, such C-reactive protein, with the pathogen. Objective The objective of this study was to evaluate the presence of H. pylori, bacterial virulence and C-reactive protein serum levels in individuals diagnosed with functional dyspepsia. Methods Were prospectively included in this study 489 dyspeptic individuals. They fulfill Rome III clinical criteria for the diagnosis of functional dyspepsia with no organic disease at endoscopy. The bacterial infection was established by histology and urease rapid test. The levels of serum C-reactive protein were obtained by immunonefelometry and CagA status ofH. pylori positive individuals was determined through an imunoenzimatic assay. Results Prevalence rate of H. pylori was 66.3% and virulence factor CagA was detected in nearly 43% of positive samples. In addition, it has been noticed an association between Ilex paraguariensis(yerba maté) consumption and pathogen's prevalence. An important effect of bacterial infection on inflammation was only observed in gastric epithelium. Conclusion No systemic response to the pathogen, measured through C-reactive protein levels, was observed, regardless of CagA status. Otherwise, the intake of yerba maté should be considered as a cultural factor possibly related toH. pylori's transmission.