A 58-year-old man with a history of hemorrhoidectomy and chronic constipation presented for routine surveillance colonoscopy. He took an over-the-counter herbal laxative containing senna for constipation. The rectal mucosa showed a brownish discoloration in a moire pattern, characteristic of melanosis coli. Advancing beyond the rectum, the full circumference of colonic mucosa turned jet black i...

Neurocutaneous melanosis is a rare congenital disorder which presents with congenital cutaneous nevi and involvement of the central nervous system. We herein present a rare case of a 2-year-old girl who had central nervous system melanosis and giant congenital melanocytic nevi. Magnetic resonance imaging, especially precontrast T1 images play a crucial role in making the diagnosis combined with...

Congenital diffuse Melanosis is one of the rarest clinical manifestations of hereditary universal Melanosis and only few cases have been reported all over the world. The presented case is a 54-year-old man who presented to us complaining of erythematous annular lesions on his face and neck since 8 months ago. Diffuse pigmentation of his skin took our attention. According to the patient, d...

esophageal melanocytosis is a rare and benign condition, characterized by melanocytic proliferation of the esophageal squamous epithelium with heavy melanin deposition. the etiology and pathogenesis has not been exactly known but it seems to be a chronic stimulus such as gastroesophageal reflux. this condition is very rare and about 35 cases have been reported so far, most of which have been fr...

An interesting example of extradermal deposition of melanin in vertebrates, notably in mammals, is splenic melanosis. In particular, if the phenomenon of splenic melanosis is correlated with hair or skin pigmentation, it must reflect the amount and perhaps the quality of pigment produced in hair follicle melanocytes. The present paper is our first study on splenic pigmentation in mice of phenot...

Esophageal melanosis which is characterized by melanocytic proliferation in the squamous epithelium of the esophagus and melanin accumulatin of esophageal mucosa (EM) is a rare disease of the digestive system. Although esophageal melanosis is considered to be a benign disease, its etiology is not cleared and has been reported to be the precursor lesion of esophageal primary melanomas. In this r...

Melanic pigmentation results from melanin produced by the melanocytes present in the basal layer of the oral epithelium. One of the most common causes of oral pigmentation is smoker melanosis, a condition associated with the melanocyte stimulation caused by cigarette smoke. This paper aims to illustrate the use of a carbon dioxide laser in the removal of the gingival melanic pigmentation for ae...