Main menu
Common skin conditions
NEWS
Join DermNet PRO
Read more
Quick links
Lichen is a Latin word meaning ‘tree moss’, referring to the symbiosis of a fungus, usually of the class Ascomycetes, and algae, resulting in a composite organism that characteristically forms a crust-like or branching growth on rocks or tree trunks. But the term ‘lichen’ is also used for various skin diseases characterized by patchy eruptions of small, firm papules. But not all the diverse skin conditions illustrated are papular; biopsy may be required to confirm diagnosis.
For each of the twelve cases, study the image(s) and then answer the questions. You can click on the image to view a larger version if required.
Each case should take approximately 2 minutes to complete. There is a list of suggested further reading material at the end of the quiz.
Name this lichenoid skin condition.
Lichen striatus
How would you treat them?
Lichen striatus is characterised by the abrupt onset of a linear plaque or two or three parallel plaques following Blaschko lines, most often affecting one limb. It is more common in children than in adults. Topical steroids may reduce itch, if present. The eruption generally resolves after a few months but may leave hypo- or hyperpigmentation for some time afterwards.