Inflammatory bowel disease (IBD) comprises two chronic, tissue-destructive, clinical entities: Crohn's disease (CD) and ulcerative colitis (UC), both immunologically based. Bowel symptoms are predominant, but extra-intestinal complications may occur, including involvement of the oral cavity. Oral involvement during IBD includes several types of lesions: the most common are aphthae; uncommon lesions include, among others, pyostomatitis vegetans and granulomatous lesions of CD. Starting with a presentation of six patients with oral manifestations, which were crucial for the final diagnosis of IBD, a review on the subject is presented. Oral involvement in IBD may be previous or simultaneous to the gastrointestinal symptoms. However, in the majority of cases, bowel disease precedes the onset of oral lesions by months or years. In many patients, the intestinal symptoms may be minimal and can go undetected; thus, most authors believe that the bowel must be thoroughly examined in all patients with suspected IBD even in the absence of specific symptoms. Usually, the clinical course of oral lesions is parallel to the activity of IBD; therefore, oral manifestations are a good cutaneous marker of IBD.

Pyostomatitis vegetans (PSV) is an intraoral pustular eruption considered by most authors to represent the mucous analogous of cutaneous pyoderma gangrenosum and its vegetating presentations (pyodermatitis vegetans). A strong correlation of PSV with inflammatory bowel disease (IBD) is well documented. The histopathology of PSV lesions usually reveals acanthosis, and neutrophils and/or eosinophils infiltration with intraepithelial or subepithelial abscesses; acantholysis is present in some cases. We studied four patients with IBD that presented oral lesions suggestive of PSV. Two male and two female patients were included. The histopathology of oral lesions of two patients revealed findings typical for PSV. The other two patients showed findings typical for pemphigus vulgaris (PV), although the course of their symptoms paralleled that of the bowel disease. Our findings may suggest that pustular lesions in patients with IBD can be a presentation of both PSV and PV; adequate diagnosis is required because clinical presentation is very similar.

We report a 52-year-old woman with micronychia of the index fingers. Radiographic examination revealed a Y-shaped bifurcation of the distal phalanx of both index fingers. She was diagnosed with congenital onychodysplasia of the index fingers (COIF) or Iso-Kikuchi syndrome. COIF is a rare condition characterized by a variety of nail dysplasia of the index fingers. Five criteria characterize COIF: congenital occurrence, unilateral or bilateral index finger involvement, variability in nail appearance, hereditary involvement and frequently associated bone abnormalities. Micronychia, polyonychia, anonychia, hemionychrogryphosis and malalignment are the observed index finger defects. Most cases have been described in Japan, and to our knowledge, this is the first case of COIF reported in South America.