title: Colonic lymphoid hyperplasia in melanosis coli.
abstract: We describe the case of a patient with Rett syndrome, a syndrome characterized by progressive infant encephalopathy, developmental delay, dementia, autism, ataxia, microcephaly, spastic paraparesis, and autonomic neuropathy with constipation. At colonoscopy, multiple foci of tiny white, sessile, polypoid lesions were seen throughout the colon and rectum, mimicking the appearances of small hyperplastic or adenomatous polyps, associated with generalized melanosis coli. This is the first case to our knowledge describing melanosis coli in a patient with Rett syndrome. As melanosis pigment deposition is characteristically not seen in lymphoid tissue, the lymphoid tissue was identifiable at endoscopy as multiple white nodules mimicking generalized colonic polyposis throughout the colon. We discuss the likely mechanisms of lymphoid hyperplasia and coexistent melanosis coli in Rett syndrome.
authors.affiliation: Queen Alexandra Hospital, Portsmouth PO6 3LY, United Kingdom.
authors.forename: C B
authors.initials: CB
authors.lastname: Pearce
authors.forename: H
authors.initials: H
authors.lastname: Martin
authors.forename: H D
authors.initials: HD
authors.lastname: Duncan
authors.forename: P M
authors.initials: PM
authors.lastname: Goggin
authors.forename: D N
authors.initials: DN
authors.lastname: Poller
mesh_terms: D015746:Abdominal Pain; D000328:Adult; D003106:Colon / Q000473:pathology*; D003108:Colonic Diseases / Q000150:complications / Q000175:diagnosis* / Q000473:pathology; D003113:Colonoscopy; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D006965:Hyperplasia; D007413:Intestinal Mucosa / Q000473:pathology; D008221:Lymphoid Tissue / Q000473:pathology; D008548:Melanosis / Q000150:complications / Q000175:diagnosis* / Q000473:pathology; D015518:Rett Syndrome / Q000150:complications* / Q000473:pathology