(Molluscum sebaceum; Molluscum epitheliale; Epithelioma contagiosum)
Definition. – A rare contagious disease characterized by pin-head- to pea-sized or larger, smooth, semi-globular, pearl-like, white or pink elevations.
Symptoms. – The lesions, of which there are seldom more than ten or twelve, are grouped upon the face especially about or on the eyelids and also in adults upon the genitals. They first appear as small pink, yellowish or pearly papules or nodules which develop to the size of a split pea, become globular in shape, firm and elastic to the touch, and presents a small opening at the summit from which a waxy or colloidal substance may be squeezed out. This small opening may appear black from the adherence of atmospheric dust. The growths are benign, unattended by constitutional symptoms and having attained their full size, the little tumors remain stationary for some months. Usually within a year they suppurate or undergo absorption and spontaneously disappear. No scar remains unless harsh treatment or infection changes the nature of the lesion. Rarely these growths increase to the size of an orange (molluscum giganteum).
Etiology and Pathology. – The disease has been successfully inoculated and is free contagious under ordinary circumstances. It is found in both sexes and at all ages but is most common among poor children, particularly among those housed in institutions. It is assumed that a parasitic element is responsible for this disease but the exact cause is not known and the pathological process is a mystery. The process probably begins in a hair-follicle and presents an enormous increase in the cells of the rete mucosum. So-called “molluscum bodies” are made up of lobules filled with degenerated epithelial cells.
Diagnosis. – The size of the lesions, their common location, waxy appearance, and central orifice giving exit to a waxy substance, should distinguish this disease from milium and from all vesicular eruptions which may be opened to show that they contain serum.
Prognosis and Treatment. – Prompt response to treatment may be expected. Because of the contagious element these cases should not be neglected, but radical treatment is never necessary because spontaneous disappearance often occurs without scarring. Careful incision with expression of contents and cauterization with the high-frequency currents, iodin, nitrate of silver or carbolic acid is sufficient. If the growths are pedunculated they may be snipped off with scissors and any of the above caustics applied. This may be followed by a dusting powder composed of one part of boric or salicylic acid to ten parts of talc. Internal medication is seldom indicated because the condition is local and constitutional symptoms are not a part of it.