CLASS III – HYPERTROPHIES [Class II- Hypertrohies]
Definition. – Pin-head- to pea-sized, multiple, circumscribed, macular pigmentations, usually on the face and hands.
Symptoms. – Freckles may be round, oval or irregular. They are usually symmetrical and often limited to parts of the skin exposed to sunlight such as the face, neck, back of hands and forearms. Yellow, brown or black in color, they may be few or many. Usually they may make their first appearance suddenly or slowly in summer and disappear partially or wholly with the advent of winter. Pigmentations which are uninfluenced by the seasons and occur on the covered as well as on the uncovered parts are called “cold freckles”. Lentigo may be primary or secondary to other changes in the skin such as occur in xeroderma pigmentosum, atrophy and senile eczema.
Etiology and Pathology. – Freckles while rarely congenital, are nearly always acquired during adolescence, but occasionally they appear as early as the fifth year. Individuals of blond complexion, especially those with red hair, are most subject. The condition is caused by exposure to solar rays of heat and light or to warm moist conditions of the air. They can be produced by the arc light or the X-rays while symptomatic forms can be traced to errors in nutrition. The pathology embraces the excessive deposit of pigment in circumscribed areas of the mucous layer of the epidermis.
Diagnosis of lentigo may be determined by the appearance of the macules between the fifth and twenty-fifth years, their location, aggravation in summer and relief in winter and their occurrence in multiple circumscribed spots.
Prognosis and Treatment. – Recurrence may be expected even after freckles have been removed. If any form of relief is necessary, it must be directed toward the removal of the epidermal cells containing the pigment. The most efficient remedy is mercuric chloride 1/2 to 4 grains to the ounce of water, or alcohol and water, applied two or three times daily on absorbent cotton. The following lotion may be used: mercuric chloride 4 to 6 grains, tincture of benzoin two drams, zinc sulphate 20 to 40 grains, and equal parts of alcohol and water enough to make four ounces. Hydrogen peroxide, full strength or weaker or lactic acid well diluted, may prove satisfactory. If an ointment is preferred the following may prove effective :
Rx Acidi salicylici, gr. xxx; 2 @
Hydrarg. ammoniat., gr. xl; 2 @4
Ungt. zinci oxidi, @
Lanolin., aa 3iv; 15 @M.
Or 25 per cent. salicylic acid with 10 per cent. resorcin in plaster may be used. If freckles are persistent even in the cold months, the use of solidified carbon dioxide affords the easiest relief. To avoid freckles, protecting veils and large hats should be worn in the summer months. Internal medication is seldom indicated except for associated non-cutaneous symptoms.