Cysts

Cysts are fortunately uncommon  but when they do occur may reach several centimetres in diameter . They may be unilocular or multilocular  and, when aspirated with a large-bore  needle, often  drain surprisingly little  thick, viscid,  creamy yellow material. Sometimes the cysts are widespread and affect the  face, back,  chest and neck, even  the scalp. The lesions may coalesce, producing boggy areas associated with  sinuses,  necrosis and granulomatous inflammation, the condition known as acne conglobata (see page  32).  Scarring is a fairly common sequel.