Coalescent papules on the eyelid margin like a string of pearls is a classic manifestation of lipoid proteinosis (LP) also called Urbach-Wiethe disease or hyalinosis cutis et mucosae. The manifestations of this disease are caused by the deposition of an amorphous hyaline material in the mucosa, skin, and elsewhere. LP is inherited AR and most patients are of European descent, including South African descendants of German or Dutch immigrants.
Hoarseness or a weak cry in infancy may be the initial manifestation and is caused by deposition of hyaline material within the vocal cords. Hoarseness may persist throughout life. Later, in childhood, pustules, blisters, hemorrhagic crusts, or erosions of the face may develop and leave depressed scars upon healing. The classic sign is bead-like papules distributed along the eyelid margin like a string of pearls. Thickened or verrucous lesions may develop on the dorsa of the hands, knees, and elbows. Morphea-like lesions and alopecia of the scalp may develop secondary to skin infiltration. Infiltrated nodules and plaques may occur in the oral mucosa. The tongue may lose mobility secondary to enlargement from infiltration. This may interfere with gustation and speech.
Bilateral, bean-shaped calcifications in the CNS may be seen radiographically. Neurologic symptoms include psychomotor and grand mal seizures, memory loss, and rage attacks. Schizophrenia may occur. Internal organs may be infiltrated, but such changes are usually asymptomatic.
The only potential threat to life is respiratory insufficiency secondary to laryngeal infiltration during infancy. Indeed, infant mortality rates may be higher than average. Adults are also at risk for laryngeal obstruction and tracheostomy has rarely been needed. Otherwise, treatment is directed at cosmesis. Dermabrasion, chemical peels, and blepharoplasty have been tried for the facial lesions. Dimethyl sulfoxide (DMSO) caused dramatic clearing in one patient after 3 years. Surgery of the vocal cords may be needed. Neurologic consultation may be appropriate.
Indian Dermatol Online J 2014;5, Suppl S2:95-7
Dermatology Online Journal 17(11)
Depressed scars. Dermatology Online Journal 14(11)