Creatinine clearance renal disease

Older adults are at increased risk for adverse reactions from the antineoplastic drugs because of the increased incidence of chronic disease, particularly renal impairment or cardiovascular disease. When renal impairment is present, a lower dosage of the antineoplastic may be indicated. Creatinine clearance isused to monitor renal function in the older adult. Blood creatinine levels are likely to be inaccurate because of a decreased muscle mass in the older adult. 

Creatinine clearance < 60 mL/min/1.73 m2 (stages III-V chronic kidney disease), diabetes mellitus (with renal insufficiency), hypertension, chronic heart failure, cirrhosis, nephrosis, age >75 yr, cholesterol emboli syndrome, multiple myeloma (questionable)... 

Probenecid is a uricosuric agent that blocks the tubular reabsorption of uric acid, increasing its excretion. Because of its mechanism of action, probenecid is contraindicated in patients with a history of uric acid stones or nephropathy. Probenecid loses its effectiveness as renal function declines and should be avoided when the creatinine clearance is 50 mL/minute or less. Its uricosuric effect is counteracted by low aspirin doses, which many patients receive for prophylaxis of coronary heart disease. 

AUC, area under the time-concentration curve ARV, antiretroviral AV, atrioventricular Cmax, maximum concentration CrCI, creatinine clearance ESRD, end-stage renal disease Cl, gastrointestinal HD, hemodialysis LFT, liver function test NRTI, nucleoside reverse transcriptase inhibitor UCT, uridine diphosphate-glucuronsyltransferase. 

Blood lead levels, urinary lead levels, serum creatinine, blood urea nitrogen (BUN), creatinine clearance (CCT), and NAG were measured in 158 male and 51 female workers in a lead battery factory or a lead smelting plant in Japan (Ong et al. 1987). Controls consisted of 30 professional and laboratory staff members with no history of renal disease or lead exposure. The length of exposure to lead averaged 10.8 8.0 years with a range of 1-36 years. Exposure levels were not available, but indicators of lead body burden in the exposed workers were PbB level = 3.0-80.0 pg/dL and urinary lead level =... 

Renal function impairment WnWe caution should be used in patients with severe renal failure, therapeutic concentrations of nalidixic acid in the urine, without increased toxicity caused by drug accumulation in the blood, have been observed in patients on full dosage with creatinine clearances (Ccr) as low as 2 to 8 mL/min. Special risk Use nalidixic acid with caution in patients with epilepsy, liver disease, or severe cerebral arteriosclerosis. 

Renal function impairment- In patients with end-stage renal disease requiring hemodialysis, dose reduction to 135 meg peginterferon alfa-2a is recommended. Closely monitor for signs and symptoms of interferon toxicity. Do not use ribavirin in patients with creatinine clearance less than 50 mL/min. 

An instructive example is the physiological variable serum creatinine. Creatinine is an endogenous metabolite formed from, and thus reflecting, muscle mass. Total body muscle mass is sufficiently constant to render measurement of serum creatinine useful for assessing actual renal function. The serum value of creatinine (R) is namely dependent on the continuous (zero-order) input of creatinine into the blood (A in) and its renal elimination rate, which is a first-order rate process (A out x ) In case of an extensive muscle breakdown, kin will temporarily increase. It may also be permanently low, for example in old age when muscle mass is reduced. Likewise, creatinine clearance may decrease for various reasons, described by a decrease in A out- An increase in creatinine clearance may occur as well, for example following recovery from renal disease. According to pharmacodynamic indirect response models. 

The good bioavailability of orally administered ciprofloxacin obviates the need for the more expensive intravenous formulation. I.v. ciprofloxacin is only given to patients who have severe sepsis or severe nausea and vomiting. Ciprofloxacin s elimination is 50% hepatic and 50% renal. Therefore, dose reduction is recommended only in case creatinine clearance drops to < 10 ml/min. Prevention of food-borne disease requires efforts at many levels. Monitoring safety of food processing, vector control, surveillance of outbreaks, education on personal hygiene and improving sanitation and access to safe water supplies are all necessary measures to reduce the incidence of GTI. 

Gouty arthritis is an inflammatory response to the deposition of monosodium urate monohydrate crystals secondary to hyperuricemia. It is called monosodium urate crystal deposition disease. Hyperuricemia is a serum urate concentration > 7 mg% in males and >6 mg% in females. Hyperuricemia results from overproduction (10-15% of individuals) or a renal excretion of urate lower than 400 mg uric acid/24 hours (85-90% of individuals). The urate under-excretors have a urate clearance of <6 ml/min or a urate to creatinine clearance ratio of <6%. The combination of a relative excess of dietary purine consumption together with urate under-excretion is often the basis for hyperuricemia. 

Dosage in renal impairment Dosage adjustment isbased on creatinine clearance. Total digitalizing dose decrease by 50% in end-stage renal disease. 

Contraindications End-stage renal disease (creatinine clearance less than 30 ml/min), severe hepatic impairment, uncontrolled angle-closure glaucoma, use within 14 days of MAOIs... 

Urine volume, creatinine clearance, BUN, electrolytes, reduction in edema, increased diuresis, decrease in body weight, reduction in blood pressure, glucose, uricacid, serum calcium (tetany), tinnitus, vertigo, hearing loss (especiallyin those at risk for ototoxicity—IV doses > 120 mg concomitant ototoxic drugs renal disease)... 

Heparin-induced thrombocytopenia and associated thromboembolic disease to prevent further thromboembolic complications IV, IV Infusion 0.2-0.4 mg/kg, IV slowly over 15-20 sec, followed by IV infusion of 0.1-0.15 mg/kg/hr for 2-10 days or longer. Dosaye in renal impairment Initial dose is decreased to 0.2 mg/kg, with infusion rate adjusted based on creatinine clearance. 

Therapeutic uses Thiazide diuretics decrease blood pressure in both the supine and standing positions postural hypotension is rarely observed, except in elderly, volume-depleted patients. These agents counteract the sodium and water retention observed with other agents used in the treatment of hypertension (for example, hydralazine). Thiazides are therefore useful in combination therapy with a variety of other antihypertensive agents including (3-blockers and ACE inhibitors. Thiazide diuretics are particularly useful in the treatment of black or elderly patients, and in those with chronic renal disease. Thiazide diuretics are not effective in patients with inadequate kidney function (creatinine clearance less than 50 mls/min). Loop diuretics may be required in these patients. 

Unfortunately, urea and creatinine will not be outside the normal range until 60% of total kidney function is lost. Hence, creatinine clearance is a more accurate measure and is used whenever renal disease is suspected or careful dosing of nephrotoxic drugs is required. 

Administering the correct dose to a patient with renal disease must therefore take into account both the extent to which the drug normally relies on renal elimination, and the degree of renal impairment the most convenient and useful guide to the latter is the creatinine clearance. These issues are now discussed. 

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