Contexto O uso de marcadores fecais para a monitorização da doença de Crohn é muito importante para a avaliação da resposta ao tratamento instituído. Objetivo Avaliar a atividade inflamatória da doença de Crohn comparando os marcadores fecais (calprotectina e lactoferrina), colonoscopia com biópsias, Crohn's Disease Activity Index (CDAI) e marcadores séricos antes do uso do Infliximabe, após a fase de indução e após a fase de manutenção. Método Foram incluídos 17 pacientes com diagnóstico prévio de doença de Crohn, que faziam uso da terapia convencional, mas que necessitaram da introdução da terapia biológica: Infliximabe. Esses pacientes realizaram colonoscopias com biópsias, exames de atividade inflamatória sérica, fecal (calprotectina e lactoferrina) e análise do CDAI nas fases pré Infliximabe, pós indução (semana 8) e pós manutenção (semana 32). Resultados Houve queda significativa (P = 0,04) da calprotectina entre as fases pré Infliximabe e pós indução, o mesmo não ocorrendo após a fase de manutenção. A lactoferrina manteve-se positiva nas três fases do estudo. Na análise histológica, houve diferença significativa apenas entre as fases pré Infliximabe e pós manutenção (P = 0,036), com 60% dos pacientes apresentando melhora histológica após o período de acompanhamento. O CDAI apresentou diferença significativa entre as fases pré Infliximabe e pós indução e entre as fases pré Infliximabe e pós manutenção (P<0,01). Conclusão A calprotectina e a lactoferrina não foram capazes de monitorizar a atividade inflamatória nos pacientes com doença de Crohn em uso de terapia biológica.

Context The use of fecal markers to monitor Crohn's disease is crucial for assessing the response to treatment. Objective To assess the inflammatory activity of Crohn's disease by comparing fecal markers (calprotectin and lactoferrin), colonoscopy combined with biopsy, and the Crohn's disease activity index (CDAI), as well as serum markers, before treatment with infliximab, after the end of induction, and after the end of maintenance. Methods Seventeen patients were included who had been previously diagnosed with Crohn's disease and were using conventional treatment but required the introduction of biological therapy with infliximab. Each patient underwent a colonoscopy with biopsy, serum, and fecal (calprotectin and lactoferrin) tests to assess inflammatory activity, and CDAI assessments before treatment with infliximab, after induction (week 8), and after maintenance (week 32). Results The calprotectin levels exhibited significant reductions (P = 0.04) between the assessment before treatment with infliximab and the end of induction, which did not occur after the end of the maintenance phase. Lactoferrin remained positive throughout the three phases of the study. Regarding the histological assessment, a significant difference was found only between the assessment before treatment and after the end of maintenance (P = 0.036), and 60% of the patients exhibited histological improvements after the completion of the follow-up period. The CDAI exhibited a significant difference between the assessment before treatment with infliximab and after induction, as well as before treatment and after maintenance (P<0.01). Conclusion Calprotectin and lactoferrin are not useful for monitoring inflammatory activity in Crohn's disease patients who are subjected to biological therapy.