Melamed-Wolinska bodies

Black Thyroid:
A benign but striking dark-brown pigmentation of thyroid follicular cells occurs in patients who take antibiotics of the tetracycline group (e.g., minocycline) for long periods of time, most commonly for acne. This pigmentation is so prominent in some cases that the gland is black on gross inspection. Cytologic preparations show abundant dark brown pigment granules within the cytoplasm
of follicular cells. The pigment is a darker brown than hemosiderin. Because the pigment stains with the Fontana stain, it is thought to represent a type of melanin. Recognizing this as a benign condition may prevent unnecessary surgery in these patients.