Renal concentrating ability

Kroll RB, Robinson GD, Chung JH. 1994b. Characterization of trihalomethane (THM)-induced renal dysfunction in the rat. I Effects of THM on glomerular filtration and renal concentrating ability. Arch Environ Contam Toxicol 27(1) 1-4. 

Another concern associated with the use of enflurane is its biotransformation, which leads to increased plasma fluoride. Following lengthy procedures in healthy patients, fluoride may reach levels that result in a mild reduction in renal concentrating ability. Thus, enflurane should be used cautiously in patients with clinically significant renal disease. 

Patients receiving lithium should avoid dehydration and the associated increased concentration of lithium in urine. Periodic tests of renal concentrating ability should be performed to detect changes. 

In a comparison of patients taking long-term lithium (n = 10) or short-term lithium (n = 9) and bipolar patients not taking lithium (n = 10), there was significantly lower creatinine clearance and renal concentrating ability in the long-term group (372). 

Hansen HE, Hestbech J, Olsen S, Amdisen A. Renal function and renal pathology In patients with lithium induced impairment of renal concentrating ability. Proc EDTA 1977 14 518-527. 

Assessment of Renal Concentrating Ability Urinary Osmolality... 

The urinary osmolality of normal individuals may vary widely, depending on the state of hydration. After excessive intake of fluids, for example, the osmotic concentration may fall as low as 50 mOsm/kg/H20, whereas in individuals with severely restricted fluid intake, concentrations of up to 1400mOsm/kg/H2O can be observed. In individuals on an average fluid intake, values of 300 to 900 mOsm/kg/H20 are typically seen. If a random urine specimen of a patient has an osmolality of >600 mOsm/kg/H20 (or >850mOsm/kg/ H2O after 12 hours of fluid restriction), it can generally be assumed that the renal concentrating ability is normal. 

While alcohol abuse may be associated with a variety of electrolyte and acid-base disorders, the role of the kidneys in this process has only recently been fully defined [164]. Renal functional abnormalities have now been related to chronic alcoholism in patients without liver disease and these defects have reverted to normal with abstinence from alcohol abuse. These abnor-mahties include decreases in the maximal reabsorptive abihty and threshold for glucose, a decrease in the threshold for phosphate excretion, and increases in the fractional excretion of P2-microglobulin, uric acid, calcium, magnesium, and amino acids. Defective tubular acidification and impaired renal concentrating ability... 

With the widespread use of lithium in the treatment of affective disorders, many questions have centered on its long-term effect on the kidneys. Of particular interest is the action of lithium at distal nephron sites where it inhibits water transport, hydrogen secretion, and possibly potassium secretion as well [10,11]. The most common side effect of chronic lithium therapy is an impairment of renal concentrating ability [11]. Lithium therapy is also associated with side effects re-... 

E6. Epstein, F. H., Beck, D., Carone, F. A., Levitin, H., and Manitius, A., Changes in renal concentrating ability produced by parathyroid extract. J. Clin. Invest. 38, 1214-1221 (1959). 

L2. Lambie, A. T., and Robson, J. S., Effect of parathyroid extract of renal concentrating ability. Lancet ii, 328-329 (1959). 

Approximately 8 to 26% of patients who receive an aminoglycoside for more than several days will develop mild renal impairment that is almost always reversible. The toxicity results from accumulation and retention of aminoglycoside in the proximal tubular cells. The initial manifestation of damage at this site is excretion of enzymes of the renal tubular brush border. After several days, there is a defect in renal concentrating ability, mild proteinuria, and the appearance of hyaline and granular casts. The glomerular... 

Hypernatremia (serum sodium > 145 mEq/L) may be caused by excessive sodium intake, excessive free water loss, or impaired renal concentrating ability. 

Free water clearance and renal concentrating ability... 

Measurement of the renal concentrating ability by the water deprivation test. 

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