Reply to Baudet et al.

We would like to thank Baudet et al. for their interest in our case report describing ”cat scratch” lesions [1]. Red linear marks or parallel corkscrew lesions have been observed in the right side of the colon [2] [3]. These endoscopic findings are considered to be the early appearance of mucosal injury without perforation resulting from barotrauma [3]. The article by McDonnell et al. highlighted to us the importance of these endoscopic findings [4]. McDonnell et al. reported a higher proportion of collagenous colitis in patients with cat scratch colon [4]. Furthermore, in patients with collagenous colitis, mucosal tears or lacerations following endoscopic air insufflation have been considered to be mucosal injury resulting from decreased compliance of the collagen-containing mucosa [5] [6] [7]. Yarze suggested these injuries were the result of barotrauma [8]. Similar findings have also been observed in patients with diversion colitis, with or without ulcerative colitis [9] [10].

Based on the above reports, we agree that the lesions described by Baudet et al. probably are endoscopic findings of mucosal injury resulting from barotrauma due to endoscopic air insufflation. However we do not accept the lesions they have described to be the same as ”cat scratch“ lesions, as these lesions do not resemble ”scratches”.

Competing interests: None

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