Lichen Simplex Chronicus Due to Mechanical Irritation

A 50-year-old male patient presented with hyperkeratotic nodules on both feet. He reported that the nodules had been slowly progressing for a number of years. The patient was a devout Muslim and prayed several times a day. This involved a sequence of barefoot movements comprising sitting, kneeling, and bowing, during which both feet rub across the prayer mat with the dorsa of the feet extended. This mechanical irritation can cause lichen simplex chronicus to develop. Due to their pathomechanism, these nodules are also referred to as “prayer nodules.” These can also develop on the knees or forehead and may be caused by other types of repetitive activity involving mechanical irritation, for example, as carried out by craftsmen. This is a chronic inflammatory lichenoid skin disorder that usually causes itch. Onset is often associated with atopic diathesisas, as in the case of this patient. Consistent treatment with soothing external agents containing urea, and, if necessary, short-term topical glucocorticoids in the case of eczematization as well as relief from mechanical irritation, results in complete resolution of the skin lesion.

Translated from the original German by Christine Rye.

Cite this as: Seier JA, Dissemond J: Lichen simplex chronicus due to mechanical irritation.

Figure.