Major ulcerative lesion
Clinical: small to large ulcer, wide undermining, well-demarcated but initially with edematous perimeter; late healing but may disseminate widely.
Histology: AFB in necrotic base and adjacent areas with pronounced undermining, and variable mineralization and vasculitis.
In the photograph of a major ulcer on the abdomen of an Angolan patient, the border is undermined with central slough and granulation tissue (left). Photomicrograph of the same lesion shows undermining and coagulation necrosis of panniculus and fascia (middle, Movat stain). Radiograph from a 10-year-old boy demonstrates contiguous involvement of the radius, a complication of an overlying lesion. There is a lytic lesion of the radius subjacent to a BU lesion over the forearm and wrist (right). In the histologic section of a punch biopsy specimen from a Congolese patient, note the contiguous coagulation necrosis in the panniculus. M. ulcerans organisms are mostly in clusters (red) in the lower panniculus but some are in the thickened necrotic interlobular septa (digital slide, Ziehl-Neelsen stain).
|
