Lichen Planus
What is lichen planus?
Lichen planus is an inflammatory disease characterized by small, flat and angular, smooth and shining, or scaly, discrete or confluent, red or violaceous-red papules, having a distinctly papular or papulo-squamous course, and attended with more or less itching.
Describe the symptoms of lichen planus.
The eruption, as a rule, begins slowly, usually showing itself upon the extremities; the forearms, wrists and legs being favorite localities. It may appear as one or more groups or in the form of short or long bands. Occasionally its evolution is rapid and a considerable part of the surface may be invaded. The lesions are pin-head to small pea-sized, irregularly grouped or so closely crowded together as to form solid patches; they are quadrangular or polygonal in shape, usually flat, with central depression or umbilication, and are reddish or violaceous in color. At first they have a glazed or shining appearance; later, becoming slightly scaly, the scaliness being more marked where solid patches have resulted. New papules may appear from time to time, the older lesions disappearing and leaving persistent reddish or brownish pigmentation. Exceptionally the eruption presents in bands or lines, like rows of beads (lichen moniliformis). Very exceptionally a vesicular or bleb tendency in some of the lesions has been noted; doubtless, in most instances at least, this has been due to the arsenic so generally administered in this disease. In rare instances lichen planus lesions are also seen on the glans penis and on the buccal mucous membrane. In some cases, especially in the region of the ankle, the papules become quite large (lichen planus hypertrophicus), and in occasional cases there is a tendency in some of the lesions or patches to clear up centrally. There is, as a rule, considerable itching. There are no constitutional symptoms.
What is the etiology of lichen planus?
In some cases the disease is distinctly neurotic in character, in others no cause can be assigned. It is more especially met with at middle age, and among the wealthier, professional, and luxurious classes.
Pathologically the first change noted in the epidermis is thought to be an acanthosis, followed by epithelial atrophy, and a hyperkeratosis, intercellular edema, and colloid degeneration of the prickle cells.
Does the disease bear any resemblance to the miliary papular syphilide, psoriasis, and papular eczema?
In some instances it does, but the irregular and angular outline, the slightly-umbilicated, flattened, smooth or scaly summits, and the dull-red or violaceous color, the history and course, of lichen planus, will serve to differentiate.
State the prognosis.
Under proper management the eruption, although often obstinate, yields to treatment.
What treatment would you prescribe in lichen planus?
A general tonic plan of medication is indicated in most cases, with such remedies as iron, quinine, nux vomica, and cod-liver oil and other nutrients. In many instances arsenic exerts a special influence, and should always be tried. Mercurials in moderate dosage have also a favorable action in most cases. Locally, antipruritic and stimulating applications, such as are used in the treatment of eczema, are to be employed, alkaline baths and tarry applications deserving special mention. Liquor carbonis detergens, applied weakened with several parts water, is a valuable application. In some cases, particularly if the disease is limited, external applications alone often suffice to bring about a cure.