Periodontal disease is associated with increased gut colonization of pathogenic Haemophilus parainfluenzae in patients with Crohn's disease.

Intestinal colonization of the oral bacterium Haemophilus parainfluenzae has been associated with Crohn's disease (CD) severity and progression. This study examines the role of periodontal disease (PD) as a modifier for colonization of H. parainfluenzae in patients with CD and explores the mechanisms behind H. parainfluenzae-mediated intestinal inflammation. Fifty subjects with and without CD were evaluated for the presence of PD, and their oral and fecal microbiomes were characterized. PD is associated with increased levels of H. parainfluenzae strains in subjects with CD. Oral inoculation of H. parainfluenzae elicits strain-dependent intestinal inflammation in murine models of inflammatory bowel disease, which is associated with increased intestinal interferon-γ (IFN-γ)+ CD4+ T cells and disruption of the host hypusination pathway. In summary, this study establishes a strain-specific pathogenic role of H. parainfluenzae in intestinal inflammation and highlights the potential effect of PD on intestinal colonization by pathogenic H. parainfluenzae strains in patients with CD.

Colonic squamous cell carcinoma in ulcerative colitis: Report of a case and review of the literature.

Squamous cell carcinoma (SCC) is a rare neoplasm in the colorectum. A case of SCC rising from an area of squamous metaplasia in the rectum is presented in a patient with long-standing ulcerative colitis and perianal warts. This is the first report in the literature describing the evolution of squamous metaplasia in the colonic mucosa into invasive carcinoma over time. Related literature on colorectal SCC and squamous metaplasia, and their relationships with inflammatory bowel disease and human papilloma virus, is reviewed.