AN HISTOLOGICAL AND ULTRASTRUCTURAL-STUDY OF THE DIRTY NECK APPEARANCE IN ATOPIC ECZEMA

The 'dirty neck' appearance is a characteristic disorder of pigmentati on, which has previously been found to affect approximately 2% of adul t atopics. This disorder results in a rippled pattern of hyperpigmenta tion similar to that seen in macular amyloidosis. Biopsy specimens fro m affected skin of three patients were examined by histological and el ectron microscopical techniques. In addition to eczematous changes, ma rked pigmentary incontinence was observed. Amyloid-like material was d etected by electron microscopy but not by light microscopy in all thre e specimens. Some deposition of amyloid occurs in this condition but t he pigmentary changes are attributable to melanin incontinence.