Chromidrosis is a functional disorder of the sweat-glands, the secretion being variously colored and generally increased in quantity. The color may be blackish, bluish, reddish, greenish or yellowish, bluish and reddish being the most common. The affection is usually local, occurring in the form of patches, the face, neck, arms, backs of the hands and feet, chest, and abdomen being the favorite localities. The disease is rare. Ferrocyanide of iron, copper, and other substances have been detected in the secretion, to the presence of which doubtless the colors are due. It is generally observed in nervous and excitable persons, chiefly in unmarried women; but it has also been noted in strong men. It tends to recur, and may appear on different parts of the body with each manifestation. The treatment should be directed against the suspected cause, with especial reference to the nervous system.
Uridrosis.
Uridrosis, or urinous sweat, is a functional disorder of the sweat-glands, the secretion containing the elements of the urine, especially urea. This latter is occasionally detected in the sweat of persons apparently in good health. In some cases, however, it exists in such quantity as to be noticeable on the skin, appearing usually on the face and hands as a colorless or whitish saline crystalline deposit or coating. In most of the marked cases reported partial or complete suppression of the renal function has preceded or accompanied the condition.
Phosphoridrosis.
Phosphoridrosis is the rare condition in which sweat is phosphorescent. It is sometimes seen in the later stages of phthisis, also in miliaria, and occasionally in persons who have eaten of putrid fish.
Sudamen.
Sudamen (syn. miliaria crystallina) is a non-inflammatory disorder of the sweat-glands characterized by pinpoint- to pinhead-sized, isolated, superficial, translucent, whitish vesicles. The lesions make their appearance on any portion of the body, but have a predilection for certain regions of the trunk, especially where the epidermis is thin. They show themselves as numerous, closely-crowded, discrete, whitish or pearl-colored minute elevations, in appearance not unlike dew-drops. They form rapidly, remaining discrete, never becoming puriform, and evince no tendency to rupture. They are non-inflammatory, never reddish in color, and are without areolæ. The fluid disappears by absorption and the epidermal covering by subsequent desquamation. The lesions may appear in successive crops or new vesicles may show themselves irregularly from time to time. On the other hand, the first outbreak may disappear rapidly, and no further manifestation show itself. Sudamina occupying the face are usually seen in middle-aged females. The vesicles here are larger, deeper-seated, and more persistent.
Constitutional debility is a predisposing cause of the disease. Diseases accompanied with a high temperature—such, for example, as typhus and typhoid fevers, tuberculosis, and acute articular rheumatism—are frequently responsible for the eruption. The vesicles are produced by the collection of sweat in some part of the sweat-duct or epidermis, usually the latter. As ordinarily seen, the vesicles are situated between the lamellæ of the horny layer, the sweat having made its way from a rupture in an obstructed duct. In those exceptional cases of deep-seated and more persistent sudamina occurring about the face, the vesicles are situated in the corium, and are caused by a dilatation of the duct. The affection is to be distinguished from miliaria by the absence of inflammatory symptoms.
The course and duration of the disease depend upon the cause. In the treatment, removal of the etiological factor is of first importance. For external use some simple dusting-powder, such as equal parts of starch and lycopodium, or frequent bathing of the parts with an evaporating lotion, such as alcohol and water or vinegar and water, may be employed.