Definition:—The persistent appearance in the urine of crystals of calcium oxalate in excess.
Etiology:—It is not uncommon to find oxalic acid represented by the calcium salt in the urine of patients in comparatively good health, but an excess may be due to faults of the central nervous system, or of digestion, especially where there is a tendency to achlorhydria. It occurs also in catarrhal jaundice, where there is mental depression, with neurasthenia, or gout, rheumatism, cancer or tuberculosis, and occasionally during diabetes. In the imperfect digestion of certain foods or incorrect metabolism it will appear, and as the result of the eating of certain fruits and vegetables, especially pears, apples, cabbage, rhubarb, asparagus, tomatoes, cauliflower, spinach, beets and carrots.
Symptomatology:—The patient is in a condition of ill health with lowered vitality. There is an indisposition to physical exercise, a tendency to despondency, and an inclination to view his condition with seriousness; there is nervous irritability, forgetfulness, with constant worry. Neurasthenia with all its concomitant symptoms and hypochondria are not uncommon.
The appetite fails, the strength abates, there are digestive disturbances which ultimately become chronic, and there is stubborn chronic constipation. The skin is dry, harsh, irritable or sensitive. There is muscular soreness, weight, aching and pain in the back, with frequency of urination with burning or scalding sensation and sharp shooting pains in the urethra.
Diagnosis:—This depends less upon the symptoms of disease than upon the presence of the characteristic crystals. The substance is kept in solution normally by the sodium phosphate., and in the absence of that phosphate may become precipitated when not in excess.
Prognosis:—The prognosis in all cases is favorable. The underlying conditions are usually tractable and the condition itself is amenable to treatment.
Treatment:—The stomach and digestion must have first attention, and the nervous system must be restored. The patient should be separated from all causes of irritability and worry, and should spend much time in the open air. He should avoid those substances which assist in the production of the oxalates, and should drink an abundance of water, as free elimination is important. Alcoholics and tea and coffee must be rigidly excluded.
The use of hydrastis, nux vomica and strychnin, quinin and iron will be serviceable. An artificial digestive should be selected according to the food taken, and should be taken with every meal. The use of nitric acid or nitro-hydrochloric acid in from from five to ten minim doses, taken in a glass of water half an hour before meals and at bedtime, will serve an excellent purpose in nearly all cases, in preventing the formation of the salt, as well as in promoting its removal.