Parry-romberg syndrome: a case of late onset with rapid progression.

Parry-Romberg syndrome (PRS) or progressive hemifacial atrophy is rare, poorly understood condition with an unclear aetiology and characterized by slow and progressive atrophy affecting one side of the face. PRS is a syndrome with diverse presentation and the most common early sign is a painless cleft, the "coup de sabre" near the midline of the face which marks the boundary between the normal and atrophic tissues. Characteristically, the atrophy starts in the first decade of life and progresses slowly for several years before it becomes quiescent. This article describes a case of PRS in a 19-year-old female patient affecting the right side of the face which is unique in the fact that it had a late onset with rapid progression.