ABSTRACT
Na síndrome de Waardenburg, genodermatose autossômica dominante, distúrbios da pigmentação (hipo ou acromia de pele e cabelos, heterocromia da íris) podem se associar a surdez, distopia do canto interno do olho e, eventualmente, outras malformações de intestino e ósseas. Os autores relatam um caso clínico da síndrome de Waardenburg tipo 2B, apresentam a classificação da doença com os critérios diagnósticos e discutem o diagnóstico diferencial, que deve ser feito com vitiligo, piebaldismo e diferentes formas de albinismo.
Waardenburg syndrome is a dominant autosomal condition in which alterations of pigmentation (hypochromia or achromia of the skin and hair, heterochromia of the iris) can be associated with deafness, lateral displacement of the inner canthi of the eyes and occasionally bowel or skeletal malformations. We report a case of Waardenburg syndrome type 2B, present the classification of the disease with diagnostic criteria and discuss differential diagnosis, which should include vitiligo, piebaldism and different forms of albinism.
ABSTRACT
The myenteric plexus undergoes adaptive changes under several conditions. Mucosal and muscular alterations of the colon have been described after fecal stream diversion but studies concerning the myenteric plexus after this procedure are scarce. Therefore, 28 Wistar rats were submitted to fecal diversion and followed for different periods (30, 60, 120 and 180 days), in order to study the myenteric plexus of the excluded segments. Seven non-operated rats were employed as control. The myenteric plexus was subsequently evaluated with the NADH and NADPH histochemical techniques. The colonic area of excluded segments is significantly decreased. The density of NADH-stained neurons continuously increases during the entire postoperative period but does not match the extent of surface reduction. Neuronal area measurements suggest hypertrophy of the remaining neurons in the late postoperative period. Morphological alterations of myenteric ganglia and neurons were also evident. An important surface area reduction combined with slight density increase points toward significant neuronal loss after fecal diversion. While studies correlating neuronal loss and functional changes are still lacking, surgeons should bear in mind the modifications of the myenteric plexus when performing fecal stream diversion surgeries.
