Urinary excretion acids

Although the average TTA value for day 5 of the soybean period was slightly lower than that for day 2, 3 subjects experienced an increased urinary acid excretion on day 5. 

Adler, S., Lindeman, R.D., Yiengst, M.J., Beard, E., and Shock, N.W. (1968) Effect of Acute Acid Loading on Urinary Acid Excretion by the Aging Human Kidney, J. Lab. Clin. Med. 72, 278-289. 

In order to lower uric acid excretion, oral purine uptake must be reduced unless one administers allopuri-nol. In view of the known tendency of patients with gout to develop renal stones one of these two measures is indicated. For patients treated with a uricosuric drug a low purine diet is certainly advisable. In order to be effective, such a diet should be supervised by repeated 24 hour collections of urine and determination of urinary acid excretion, as explained above. 

Table 7.5 Mean urinary acid excretion of 21 normal subjects (from Witten et al, 1973).

Of the water-soluble vitamins, intakes of nicotinic acid [59-67-6] on the order of 10 to 30 times the recommended daily allowance (RE)A) have been shown to cause flushing, headache, nausea, and moderate lowering of semm cholesterol with concurrent increases in semm glucose. Toxic levels of foHc acid [59-30-3] are ca 20 mg/d in infants, and probably approach 400 mg/d in adults. The body seems able to tolerate very large intakes of ascorbic acid [50-81-7] (vitamin C) without iH effect, but levels in excess of 9 g/d have been reported to cause increases in urinary oxaHc acid excretion. Urinary and blood uric acid also rise as a result of high intakes of ascorbic acid, and these factors may increase the tendency for formation of kidney or bladder stones. AH other water-soluble vitamins possess an even wider margin of safety and present no practical problem (82). 

Lauwerys R, Buchet J-P, Roels HA, et al. 1974. Relationship between urinary delta-aminolevulinic acid excretion and the inhibition of red cell delta-aminolevulinate dehydratase by lead. Clin Toxicol 7 383-388. 

Schwartz BS, Lee BK, Stewart W, et al. 1997. Delta-aminolevulinic acid dehydratase genotype modifies four hour urinary lead excretion after oral administration of dimercaptosuccinic acid. Occup Environ Med 54(4) 241-246. 

In a study with 40 healthy men and women, average age 63.7 years, who were randomized to either an alkali diet (meat plus fruits and vegetables) or an acid diet (meat plus cereal grains) (Jajoo and others 2006), altering the renal net acid excretion over a period of 60 days affected several biochemical markers of bone turnover and calcium excretion. The acidity of the diet had a significant effect on increasing NTX, a urinary marker of bone breakdown, and increasing the amount of calcium excreted in the urine. 

Prophylactic treatment can be withheld if the first episode of acute gouty arthritis was mild and responded promptly to treatment, the patient s serum urate concentration was only minimally elevated, and the 24-hour urinary uric acid excretion was not excessive (less than 1,000 mg/24 hours on a regular diet). 

The urine frequently contains casts and amorphous debris, but rarely any considerable number of red blood corpuscles. Proteinuria and aminoaciduria are found in nearly all untreated patients from a very early age. The proteinuria is usually reported as albuminuria in the literature, but in some cases the urinary protein has been shown by electrophoresis to consist largely of a-globulin and other relatively low-molecular-weight proteins (B21). A similar urinary pattern occurs in a number of diseases of the renal tubule. The proteinuria is often only moderate in degree, e.g., < 50 to 150 mg protein per 100 ml of urine, but is easily detected by the conventional tests for protein, such as salicylsulfonic acid. Excretion of protein can rise to nearly 1 g/100 ml in some cases (H8, L7). 

Ml. Marko, A. M., Gerrard, J. W., and Buchan, D. J., Glutamic acid derivatives in adult celiac disease. II. Urinary total glutamic acid excretion. Can. Med. Assoc. J. 83, 1324-1325 (1960). 

Omnivores excrete a more acidic urine than herbivores. Investigators have demonstrated increased urinary acid and calcium by feeding acid-producing chemicals. 

Such acid and calcium excretion may be important in development of osteoporosis. To test diets of meat and vegetable protein upon urinary acid and calcium, nine human adults, aged 22 to 69 years, were fed isonitrogenous diets of chicken or soy beans in seven-day feeding periods. Diets provided daily ... 

The meat diet resulted in markedly greater titratable acid and calcium excretion compared with the soy diet (P<0.02). This occurred despite the fact that each diet contained the same amounts of protein, calcium, phosphorus, and sulfur. Increased urinary calcium excretion in subjects accompanied this increased output of TTA (P<0.02) ... 

Earlier animal work showed similar results in terms of urinary acid production from dietary precursors that could be converted into acid before excretion. However, most investigators used salts rather than foods containing the anion or its precursor. The addition of acid, in the form of hydrochloric, sulfuric, or ammonium chloride, acid phosphate salts, or ascorbate resulted in enhanced urinary acidity and concomitant calcium excretion. For example, in the detailed study of bone salt metabolism, Barzel and Jowsey (19) showed that the rat fed supplementary ammonium chloride subsequently lost more calcium, and developed markedly demineralized fat-free bone mass. 

Since this increased calcium loss, the quality of dietary protein may be important in conserving body calcium in the bone reservoir via the kidney. Human renal studies have corroborated animal data in-so-far as calcium excretion as influenced by urinary acidity is concerned. This was emphasized by Marone et al. (15) who reported increased excretion of calcium in the acidotic dog and by Zemel, et al. (27) who studied calcium filtration by the kidney. They fed subjects low or high-protein (50 or 150 g/d) diets, then compared... 

This phenomenon also had been reported in human subjects fed acid ash foods. Farquharson, et al. (33) fed a high-protein (200 g) diet to human subjects who promptly excreted more urinary acid and calcium. This occurred whether the protein level was raised to 200 g, or an equivalent amount of ammonium chloride was fed. If, on the other hand, the acid ash in the protein were neutralized with sodium bicarbonate, the hypercalciuria did not occur. 

In an industrial plant in which the airborne chromic acid concentrations measured from 0.18 to 1.4mg/m/ moderate irritation of the nasal septum and turbinates was observed after 2 weeks of exposure, ulceration of the septum was present after 4 weeks, and there was perforation of the septum after 8 weeks. A worker exposed to an unmeasured concentration of chromic acid mist for 5 years developed jaundice and was found to be excreting significant amounts of chromium liver function was mildly to moderately impaired in four other workers with high urinary chromium excretion. ... 

Urinary diterpenes excretion. Absorption and excretion of the cholesterol-raising coffee diterpenes cafestol and kahweol were observed in nine healthy patients with ileostomies. Ileostomy effluent was collected for 14 hours, and urine was collected for 24 hours. Approximately 70% of the ingested cafestol and kahweol was absorbed. Only small part of the diterpene was excreted as a conjugate of glucuronic acid or sulphate in urine, mean excretion was 1.2% of the ingested amount for cafesterol and 0.4% for kahweol . 

Mechanism of Action A uricosuric that increases urinary excretion of uric acid, thereby decreasing blood urate levels. Therapeutic Effect Promotes uric acid excretion and reduces serum uric acid levels. 

Inoue, O., Seiji, K., Kudo, S., Jin, C., Cai S.-X., Liu, S.-J., Watanabe, T., Nakatsuka, H. Ikeda, M. (1995) Urinary phenylglyoxylic acid excretion after exposure to ethylbenzene among solvent-exposed Chinese workers. Int. J. occup. environ. Health, 1, 1-8 Johnstone, R.A.W., Quan, P.M. Carmthers, W. (1962) Composition of cigarette smoke some low-boiling components. Nature, 195, 1267-1269 Jonsson, A., Persson, K.A. Grigoriadis, V (1985) Measurement of some low molecular-weight oxygenated aromatic and chlorinated hydrocarbons in ambient air and in vehicle emissions. Environ, int., 11, 383-392... 

As the urinary excretion of uric acid increases, the size of the urate pool decreases, although the plasma concentration may not be greatly reduced. In patients who respond favorably, tophaceous deposits of urate are reabsorbed, with relief of arthritis and remineralization of bone. With the ensuing increase in uric acid excretion, a predisposition to the formation of renal stones is augmented rather than decreased therefore, the urine volume should be maintained at a high level, and at least early in treatment the urine pH should be kept above 6.0 by the... 

Progesterone decreases the plasma levels of many amino acids and leads to increased urinary nitrogen excretion. It induces changes in the structure and function of smooth endoplasmic reticulum in experimental animals. 

Therapy with hydrochlorothiazide, up to 50 mg twice daily, or chlorthalidone, 50-100 mg daily, is recommended. Loop diuretics such as furosemide and ethacrynic acid should not be used because they increase urinary calcium excretion. The major toxicity of thiazide diuretics, besides hypokalemia, hypomagnesemia, and hyperglycemia, is hypercalcemia. This is seldom more than a biochemical observation unless the patient has a disease such as hyperparathyroidism in which bone turnover is accelerated. Accordingly, one should screen patients for such disorders before starting thiazide therapy and monitor serum and urine calcium when therapy has begun. 

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