Abnormal renal function

Metabolic alkalosis is maintained by abnormal renal function that prevents the kidneys from excreting excess bicarbonate. 

Following a single oral dose of 15 to 25 mg/kg, ethambutol attains a peak of 2 to 5 mcg/mL in serum 2 to 4 hours after administration. Serum levels are similar after prolonged dosing. The serum level is undetectable 24 hours after the last dose except in some patients with abnormal renal function. 

Hypersensitivity to polyoxyethylated castor oil (injection only see Warnings and Administration and Dosage), cyclosporine, or any component of the products Gengraf and Neoral in psoriasis or RA patients with abnormal renal function, uncontrolled hypertension, or malignancies Gengraf and A/eora/concomitantly with PUVA or DVB, methotrexate or other immunosuppressive agents, coal tar or radiation therapy in psoriasis patients. 

Foscarnet should not be used in combination with drugs that cause renal toxicity (e.g., acyclovir, aminoglycosides, amphotericin B, NSAIDs). Abnormal renal function has been noted when foscarnet is used with ritonavir or ritonavir and saquinavir. Pentamidine may increase the risk of nephrotoxicity, hypocalcemia, and... 

Several drugs, such as the antifolate compound methotrexate or the anaesthetic gas nitrous oxide, may interfere with methionine metabolism and lead to mild increases of Hey [2]. Abnormal renal function has been shown to lead to increased plasma Hey, for example, in end-stage renal disease patients [15]. 

Abnormal renal function, including acute renal failure, decreased serum creatinine clearance, and increased serum creatinine... 

An unusual case of rapidly fatal renal failure reported in 1993 could reflect an interaction between tamoxifen and one or more cytostatic agents, with mitomycin C a prime suspect in a series of breast cancer patients some 10% of those treated both with tamoxifen and a cytostatic agent developed abnormal renal function, progressing towards various stages of hemolytic-uremic syndrome (118). 

When to stop metformin in people with diabetes mellitus and abnormal renal function continues to be debated. It has been suggested that it should not be used in those with an eGFR (MDRD) of less than 60 ml/minute (122). However, this would exclude many people who have been taking metformin for many years without apparent ill effect. Others have recommended using the Cockcroft-Gault equation (SEDA-29, 527), which is preferable. 

The camptothecins are natural products that are derived from the Camptotheca acuminata tree, and they inhibit the activity of topoisomerase I, the key enzyme responsible for cutting and religating single DNA strands. Inhibition of the enzyme results in DNA damage. Topotecan is indicated in the treatment of patients with advanced ovarian cancer who have failed platinum-based chemotherapy and is also approved as second-line therapy of small cell lung cancer. The main route of elimination is renal excretion, and for this reason caution must be exercised in patients with abnormal renal function, with dosage reduction being required. 

The use of contrast media in patients taking metformin should be carried out cautiously. Contrast-induced nephropathy can lead to retention of metformin and lactic acidosis. However, there is no conclusive evidence that intravascular contrast agents precipitate metformin-induced lactic acidosis in patients with normal serum creatinine concentrations (under 130 pmol/1). This complication was almost always observed in non-insulin dependent diabetic patients with abnormal renal function before injection of contrast media (4,316). 

As noted above, hyperkalemia often complicates the NSAID-induced acute renal deterioration. However, the severity of hyperkalemia can be disproportionate to the degree of renal impairment. Tan et al. [56] have reported a patient who had a serum potassium level of 6.2 mEq/L in spite of only mildly abnormal renal function. In this patient, plasma renin and aldosterone levels were suppressed and failed to respond to furo-semide or postural changes. Urinary prostaglandin Ej was also suppressed. Discontinuation of indomethacin resulted in normalization of potassium, prostaglandin Ej, and a rebound of renin and aldosterone. 

Pinto-Sietsma SJ, Mulder J, Janssen WM, Hillege HL, de Zeeuw D, de Jong PE Smoking is related to albuminuria and abnormal renal function in nondiabetic persons. Ann/nfern/MecM 33 585-591,2000. 

Renal Effects. Renal function tests were performed in two individuals who had been immersed in gasoline for several hours (Hansbrough et al. 1985 Simpson and Cruse 1981). There was no evidence of abnormal renal function in either case. 

Coal Tar Products. Elevated red and white cell counts in urine were noted in 6-8% (29-34 of 452) of the employees examined in an industrial health survey in nine coal tar plants in which coal tar creosote and coal tar were the main treatments used (TOMA 1981). Some of these cell count elevations were attributed to urinary tract infections resulting from inadequate personal hygiene, and not to industrial exposure to toxic chemicals. However, some of the workers with elevated red and white cell counts in urine had cellular and granular casts and traces of protein, suggesting abnormal renal function. These individuals were referred to their physicians for diagnosis. No determination of exposure was made at the nine coal tar plants (TOMA 1981). Moreover, no clear relationship could be established because exposure routes in addition to inhalation (e.g., oral and dermal) were likely. Also, the ability to relate renal effects to coal tar creosote and coal tar exposure was further confounded by the possibility that the subjects were also exposed to other chemicals and cigarette smoke. Additional limitations of the study included seasonal and geographical variation in plant locations, past employment history, voluntary participation in the study that could have biased it in favor of healthy workers, lack of statistical analyses, lack of adequate controls, and use of only current employees. 

Mazze Rl, Sievenpiper TS, Stevenson J. Renal effects of enflurane and halothane in patients with abnormal renal function. Anesthesiology 1984 60 161-163. 

The overall picture is that no clinically important adverse interaction occurs between digoxin and ACE inhibitors in patients with normal renal function, and that serum digoxin monitoring is only needed in those who have a high risk of reversible ACE inhibitor induced renal failure (e.g. patients with congestive heart failure during chronic diuretic treatment, with bilateral renal artery stenosis or unilateral renal artery stenosis in a solitary kidney) however, note these latter two conditions are contraindications to the use of ACE inhibitors. The critical factor does not seem to be the particular ACE inhibitor used but the existence of abnormal renal function or conditions that increase the risk of renal impairment. This needs confirmation. 

Glomerular filtration rate (GFR) is the best global estimate of renal function. Insulin clearance is the gold standard for GFR measurement. Greatinine clearance may also be used, although its value exceeds the exact value for GFR because creatinine is not exclusively excreted by the tubules but also secreted by the tubules. This discrepancy increases as GFR falls. Serum creatinine measurement does not reflect abnormal renal function until after GFR has been reduced to at least 50% of the baseline value [6]. 

Abnormal renal function is commonly found in people using lithium, but may relate to other factors, e.g. vascular disease ... 

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