RESUMEN
BACKGROUND: The compositional nature of the pigment of melanosis coli is essentially unknown. Previous histochemical studies suggested that this pigment has certain similarities with lipofuscin (i.e., age-dependent pigment) and ceroids (i.e., pathologically derived pigments) and that it may contain, therefore, polymerized glycolipids and glycoproteins. However, the saccharide composition of this pigment was never explored by lectin histochemical procedures, which was the main object of this study. METHODS: Colonoscopic biopsy specimens from eight patients with melanosis coli and from three normal control subjects were studied by fluorescent microscopy and by standard and lectin histochemistry. The number of apoptoses in the lining colonic epithelium was also evaluated histologically. RESULTS: Apoptotic bodies were significantly more numerous in patients with melanosis coil than in control subjects. The pigment that accumulates in macrophages of the lamina propia showed autofluorescence, sudanophilia, acid-fastness, and positiveness to PAS and Schmorl's reactions, all of which are common to lipofuscin and ceroids, plus an intense argentaffin reaction abolished by bleaching, indicative of a melanic substance. Lectin histochemistry showed, in decreasing order of frequency, the presence of alpha-D-mannose, sialic acid, beta-D-galactose (lactose), gal-beta-(1-3)acetyl-galactosamine, alpha-D-galactose, and alpha-L-fucose, but no terminal alpha-D-acetyl-galactosaminyl residues. CONCLUSIONS: The significant increase of apoptotic bodies in the lining colonic epithelium indicated that this type of cell death is not due to the natural programmed cell renewal, but to the action of laxatives. Because the autofluorescent pigment of melanosis coli contains melanin (as well as glycoconjugates) and is not dependent on age but on the use of anthranoid laxatives, it should be categorized as a "melanized ceroid." The lectin affinities of this pigment indicated that it contains a substantial number of saccharide residues almost similar to those found in the ceroid pigment of human aortic atheromas. These findings and considerations on the metabolism and pharmacokinetics of anthranoids suggested that the apoptotic epithelial cells, rather than the laxatives, may be the source of the pigment saccharides, whereas the precursors of the melanic substance may be derived from the anthranoids.
Asunto(s)
Antraquinonas/efectos adversos , Catárticos/efectos adversos , Colon/efectos de los fármacos , Enfermedades del Colon/inducido químicamente , Enfermedades del Colon/metabolismo , Melanosis/inducido químicamente , Melanosis/metabolismo , Pigmentos Biológicos/química , Adulto , Anciano , Anciano de 80 o más Años , Apoptosis , Biopsia , Estudios de Casos y Controles , Ceroide/análisis , Colon/patología , Enfermedades del Colon/patología , Femenino , Humanos , Inmunohistoquímica , Mucosa Intestinal/efectos de los fármacos , Mucosa Intestinal/patología , Lectinas , Masculino , Melaninas/análisis , Melanosis/patología , Microscopía Fluorescente , Persona de Mediana Edad , Extracto de Senna/efectos adversosRESUMEN
Presentamos un caso de melanodermitis tóxica liquemoide, dermatosis profesional poco frecuente por el uso actual de lubricantes de mejor purificación. Consideramos que debe incluirse dentro de las melanosis cérvico faciales, debido a la rareza con que este cuadro se localiza en otras zonas expuestas como dorso de manos y/o antebrazos
Asunto(s)
Humanos , Masculino , Anciano , Melanosis/etiología , Melanosis/inducido químicamente , Melanosis/patología , Enfermedades Profesionales , Hidrocarburos/efectos adversos , Antracenos/efectos adversos , Benzopirenos/efectos adversos , Trastornos por Fotosensibilidad/diagnósticoRESUMEN
Presentamos un caso de melanodermitis tóxica liquemoide, dermatosis profesional poco frecuente por el uso actual de lubricantes de mejor purificación. Consideramos que debe incluirse dentro de las melanosis cérvico faciales, debido a la rareza con que este cuadro se localiza en otras zonas expuestas como dorso de manos y/o antebrazos
Asunto(s)
Humanos , Masculino , Anciano , Melanosis/etiología , Antracenos/efectos adversos , Benzopirenos/efectos adversos , Hidrocarburos/efectos adversos , Melanosis/inducido químicamente , Melanosis/patología , Enfermedades Profesionales , Trastornos por Fotosensibilidad/diagnósticoRESUMEN
This report describes four patients with chronic psoriasiform dermatitis of the palms and soles who developed pigmented macular lesions after localized photochemotherapy (PUVA) to these areas. These lesions had varied histopathologic presentations including lentigines, atypical melanocytic proliferation and a junction nevus suggesting a wide clinico pathologic spectrum in the PUVA-induced pigmented macules.
Asunto(s)
Lentigo/inducido químicamente , Nevo Pigmentado/inducido químicamente , Terapia PUVA/efectos adversos , Neoplasias Cutáneas/inducido químicamente , Anciano , Femenino , Humanos , Masculino , Melanosis/inducido químicamente , Persona de Mediana Edad , Psoriasis/tratamiento farmacológicoRESUMEN
This report describes four patients with chronic psoriasiform dermatitis of the palms and soles who developed pigmented macular lesions after localized photochemotherapy (PUVA) to these areas. These lesions had varied histopathologic presentations including lentigines, atypical melanocytic proliferation and a junction nevus suggesting a wide clinico pathologic spectrum in the PUVA-induced pigmented macules
Asunto(s)
Humanos , Persona de Mediana Edad , Masculino , Femenino , Lentigo/inducido químicamente , Neoplasias Cutáneas/inducido químicamente , Nevo Pigmentado/inducido químicamente , Terapia PUVA/efectos adversos , Melanosis/inducido químicamente , Psoriasis/tratamiento farmacológicoRESUMEN
Se presenta una nelanodermitis tóxica liquenoide del ala nasal izquierda de la nariz a la que se le había indicado extirpación quirúrgica con márgenes, por habérsela diagnosticado como lentigo maligno de Hutchinson. Se incorpora así la melanodermitis tóxica liquenoide al grupo de simuladores de malignidades melanocíticas
Asunto(s)
Persona de Mediana Edad , Humanos , Masculino , Dermatitis Profesional/diagnóstico , Melanosis/diagnóstico , Diagnóstico Diferencial , Melanosis/inducido químicamente , Melanosis/patología , Nariz , Petróleo/efectos adversosRESUMEN
Se presenta una nelanodermitis tóxica liquenoide del ala nasal izquierda de la nariz a la que se le había indicado extirpación quirúrgica con márgenes, por habérsela diagnosticado como lentigo maligno de Hutchinson. Se incorpora así la melanodermitis tóxica liquenoide al grupo de simuladores de malignidades melanocíticas (AU)