Nephrolithiasis diuretics

Some drugs can cause hyperuricemia and gout, such as thiazide diuretics, niacin, pyrazinamide, cyclosporine, and occasionally, low-dose aspirin. In most cases, these drugs block uric acid secretion in the kidney. Long-term consequences of gout and hyperuricemia include joint destruction, tophi, and nephrolithiasis. 

The answer is a. (Katzung, pp 255-256.) Thiazide diuretics can be used in the treatment of nephrogenic diabetes insipidus. Its other uses include the treatment of hypertension, CHF, and nephrolithiasis due to idiopathic hypercalcuria. 

See Table 15-5. The major indications for thiazide diuretics are (1) hypertension, (2) heart failure, (3) nephrolithiasis due to idiopathic hypercalciuria, and (4) nephrogenic diabetes insipidus. Use of the thiazides in each of these conditions is described in Clinical Pharmacology of Diuretic Agents. 

In renal stone formers, in addition to general measures (low calcium diet, high fluid intake), urinary calcium may be diminished by a thiazide diuretic (with or without citrate to bind calcium) and oral phosphate (see above). See also Nephrolithiasis (p. 543). 

Diuretics have a wide range of clinical uses, including HTN, heart failure, edematous states, renal dysfunction, hypercalcemias, nephrolithiasis, glaucoma, and mountain sickness. Although they are classed as diuretics, recognize that both loops and thiazides cause significant vasodilation, an action that contributes to their clinical effectiveness, especially in HTN and heart failure. 

Answer A. The effects described are typical of thiazide diuretics, which inhibit the Na+/Cr cotransporter in the distal convoluted tubule. This action facilitates reabsorption of Ca2+, which is the basis for the use of thiazides in nephrolithiasis, and which can result in hypercalcemia. The increased load of Na+ in the collecting tubules leads to increased excretion of both K+ and H+, so hypokalemia and alkalosis may occur. 

Thiazide diuretics, which reduce urinary excretion of Ca, sometimes are employed to treat calcium nephrolithiasis and may be useful for the treatment of osteoporosis see Chapter 61). Thiazide diuretics also are a mainstay for treatment of nephrogenic diabetes insipidus, reducing urine volume by up to 50%. The mechanism of this paradoxical effect remains unknown. Since other hahdes are excreted by renal processes similar to those for Cl", thiazide diuretics may be useful for the management of Br" intoxication. 

Thiazide diuretic prototype acts in distal convoluted tubule (DCT) to block Na+/Cl transporter used in HTN, CHF, nephrolithiasis. Tox a sulfonamide increased serum lipids, uric acid, glucose K wasting. 

Traditional Medicine. Used as a diuretic and expectorant, to reduce blood cholesterol, and in treating nephrolithiasis (kidney stones), diabetes, chronic skin diseases, and liven ailments, among others. ... 

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