OXAVIIPIA, or TILE OXALIC Am) DrATtr'Ests, is a morbid condition of the system, in which one of the most prominent symptoms is the persistent occurrence of crystals of oxalate of lime in the urine. These crystals most commonly occur as very minute transparent octohedra, but sometimes in the form of dumb-bells; in order to detect them the urine, which usually in these cases presents a mucous cloud, should be allowed to stand for some hours in a conical glass, and after the crystals have gradually snhsided, the greater part of the fluid should be poured away, and the drops remaining at the bottom examined with a power of not less titan 200 diameters. These crystals, which are insoluble in acetic acid, may occur either in acid or in alkaline urine.
Per sons who secrete this form of urine are usually dyspeptic, hypochondriacal, and liable to attacks of boils, cutaneous ernptioas, and neuralgia. The oxalic acid in these eases is not introduced into the system with the food, but is a product of the disintegration of the tissues, and is due to the imperfect oxidation of compounds, which should normally have been converted into carbonic acid. (Anhydrous oxalic acid, C.O,, obviously requires 2 equivalents of oxygen to be converted into carbonic acid, C.O., or Hence, if these two equivalents of oxygen are wanting in the system, in consequence of imperfect oxygenation of the blood, oxalic acid, in combination with lime. appears as a
final excretion in place of carbonic acid.) The occurrence of oxalic acid as a persistent sediment in the urine is not only an indication of an existing morbid condition of the system, but may give rise to two perfectly distinct dangerous complications; (1) a con cretion of oxalate of lime (mulberry calculus) may be formed either in the kidney or the bladder; and (2) had consequences may arise from the poisonous action of the oxalic acid on the digestive organs, on the heart, and on the nervous system.
The treatment is simple. Care must be taken that the patient should avoid articles of diet containing oxalic acid (such as sorrel, rhubarb, tomatoes, etc.), or readily efIll• verted into it (such as sugar), and all drinks containing much carbonic acid; while he should take plenty of exercise in the open air without fatiguing himself; should use the shower-bath, unless lie feels chilled and depressed after its application, in which case lie should rub the body all over daily with a horse-hair glove; and should employ as a Ionic medicine either a little ruitronmmriatic acid in a bitter infusion (20 minims of the acid in an ounce and a half of infusion of chyretta), or live grains of citrate of iron and quinine three times daily. Under this treatment the oxalates usually- almost entirely disappear from the urine in two or three weeks.