Lichen simplex chronicus (neurodermatitis)

Published on 02/04/2015 by admin

Filed under Internal Medicine

Last modified 22/04/2025

Print this page

rate 1 star rate 2 star rate 3 star rate 4 star rate 5 star
Your rating: none, Average: 0 (0 votes)

This article have been viewed 1158 times

191 Lichen simplex chronicus (neurodermatitis)

Instruction

Look at this patient’s skin.

Salient features

History

• Itching (self-perpetuating scratch-itch cycle).

Examination

• Several scratch marks (from pruritus)

• Well-circumscribed plaque with lichenified or dry, thickened, leathery skin (Fig. 191.1)

• Look for similar plaques in common areas, including the posterior nuchal region, wrists, perineum, dorsum of the feet or ankles (Fig. 191.2).

image

Fig. 191.1 Lichen simplex chronicus.

image

Fig. 191.2 Lichen simplex chronicus.

(With permission from Habif 2009.)

Diagnosis

This patient has lichen simplex chronicus (lesion), which is caused by chronic itching and scratching (aetiology) and is cosmetically disturbing to the patient.

Advanced-level questions

How would you treat such a patient?

• Break the scratch–itch–scratch cycle by adminstering antipruritic agents

• High-potency topical steroids (under occlusion or intralesional injection)

• The area should be protected

• Patient should be made aware of when he or she is scratching.

What is the prognosis?

The disease tends to remit during treatment; however, it may recur or develop at another site.

What is the classification of itch?

Twycross (Q J Med 2003;96:7–26) classification of itch is based on peripheral and central origins of itch:

• Pruritoceptive itch is itch that originates in the skin, from inflammation, dryness or other skin damage, and is transmitted by nerve C-fibres, e.g. itch caused by reactions to insect bite, scabies, urticaria.

• Neuropathic itch is itch that arises because of disease located at any point along the afferent pathway, e.g. post-herpes zoster neuropathy, the itch occasionally associated with multiple sclerosis and brain tumours.

• Neurogenic itch is itch that originates centrally but without evidence of neural pathology, e.g. itch of cholestasis, which is the result of the action of opioid neuropeptides on opioid µ-receptors.

• Psychogenic itch, as in the delusional state of parasitophobia.

Often one type of itch can coexist with another, for example in the itch of atopic eczema, neurogenic as well as pruritoceptive itches seem to arise in the same patient.

Which spinal tracts conduct itch and pain information?

Information on itch and pain is conveyed centrally in two separate systems that both use the lateral spinothalamic tract.

Related posts:

Default ThumbnailSixth cranial nerve palsy Osteoarthrosis Cataracts Ebstein’s anomaly Paget’s disease Felty’s syndrome