title: Minocycline-related cutaneous hyperpigmentation as demonstrated by light microscopy, electron microscopy and X-ray energy spectroscopy.
abstract: A 70-year-old patient with a chronic cutaneous ulcer treated by minocycline hydrochloride developed hyperpigmentation of the forearms. Biopsy material was studied by light microscopy, electron microscopy and X-ray energy spectroscopy. Granular gold-brown pigment was found in dermal histiocytes and eccrine myoepithelial cells, which gave positive reaction with Prussian blue and Fontana-Masson stains. Electron microscopy revealed intracytoplasmic granules of dark, homogeneous material and small fine particles. X-ray energy spectroscopy showed iron and other elements in smaller amounts. The different types of minocycline-related hyperpigmentation and the possible pathomechanism are discussed with special regard to the importance of the diagnostic methods.
mesh_terms: D000368:Aged; D003594:Cytoplasmic Granules / Q000648:ultrastructure; D004577:Electron Probe Microanalysis; D006801:Humans; D007501:Iron / Q000378:metabolism; D008297:Male; D008911:Minocycline / Q000009:adverse effects*; D010859:Pigmentation Disorders / Q000139:chemically induced* / Q000378:metabolism / Q000473:pathology; D012867:Skin / Q000378:metabolism / Q000648:ultrastructure*; D012880:Skin Pigmentation / Q000187:drug effects*; D013754:Tetracyclines / Q000009:adverse effects*
chemical_list: D013754:Tetracyclines; D007501:Iron; D008911:Minocycline