Items in AFP with MESH term: Creatinine
ABSTRACT: The Kidney Disease Outcome Quality Initiative of the National Kidney Foundation published clinical practice guidelines on chronic kidney disease in February 2002. Of the 15 guidelines, the first six are of greatest relevance to family physicians. Part II of this two-part review covers guidelines 4, 5, and 6. Glomerular filtration rate is the best overall indicator of kidney function. It is superior to the serum creatinine level, which varies with age, sex, and race and often does not reflect kidney function accurately. The glomerular filtration rate can be estimated using prediction equations that take into account the serum creatinine level and some or all of specific variables (age, sex, race, body size). In many patients, estimates of the glomerular filtration rate can replace 24-hour urine collections for creatinine clearance measurements. Urine dipsticks generally are acceptable for detecting proteinuria. To quantify proteinuria, the ratio of protein or albumin to creatinine in an untimed (spot) urine sample is an accurate alternative to measurement of protein excretion in a 24-hour urine collection. Patients with persistent proteinuria have chronic kidney disease. Other techniques for evaluating patients with chronic kidney disease include examination of urinary sediment, urine dipstick testing for red and white blood cells, and imaging studies of the kidneys (especially ultrasonography). These techniques also can help determine the underlying cause of chronic kidney disease. Family physicians should weigh the value of the National Kidney Foundation guidelines for their clinical practice based on the strength of evidence and perceived cost-effectiveness until additional evidence becomes available on the usefulness of the recommended quality indicators.
Diabetic Nephropathy: Common Questions - Article
ABSTRACT: Diabetic nephropathy, or diabetic kidney disease, affects 20 to 30 percent of patients with diabetes. It is a common cause of kidney failure. Diabetic nephropathy presents in its earliest stage with low levels of albumin (microalbuminuria) in the urine. The most practical method of screening for microalbuminuria is to assess the albumin-to-creatinine ratio with a spot urine test. Results of two of three tests for microalbuminuria should be more than 30 mg per day or 20 mcg per minute in a three- to six-month period to diagnose a patient with diabetic nephropathy. Slowing the progression of diabetic nephropathy can be achieved by optimizing blood pressure (130/80 mm Hg or less) and glycemic control, and by prescribing an angiotensin-converting enzyme inhibitor or angiotensin receptor blocker. Patients with diabetes and isolated microalbuminuria or hypertension benefit from angiotensin-converting enzyme inhibitors or angiotensin receptor blockers. In the event that these medications cannot be prescribed, a nondihydropyridine calcium channel blocker may be considered. Serum creatinine and potassium levels should be monitored carefully for patients receiving angiotensin-converting enzyme inhibitors or angiotensin receptor blockers. These medications should be stopped if hyperkalemia is pronounced.
Management of Acute Renal Failure - Article
ABSTRACT: Acute renal failure is present in 1 to 5 percent of patients at hospital admission and affects up to 20 percent of patients in intensive care units. The condition has prerenal, intrarenal, and postrenal causes, with prerenal conditions accounting for 60 to 70 percent of cases. The cause of acute renal failure usually can be identified through an appropriate history, a physical examination, and selected laboratory tests. The initial laboratory evaluation should include urinalysis, a determination of the fractional excretion of sodium, a blood urea nitrogen to creatinine ratio, and a basic metabolic panel. Management includes correction of fluid and electrolyte levels; avoidance of nephrotoxins; and kidney replacement therapy, when appropriate. Several recent studies support the use of acetylcysteine for the prevention of acute renal failure in patients undergoing various procedures. The relative risk of serum creatinine elevation was 0.11 in patients undergoing radiocontrast-media procedures (absolute risk reduction: 19 percent) and 0.33 in patients undergoing coronary angiography (absolute risk reduction: 8 percent). In patients pretreated with sodium bicarbonate before radiocontrast-media procedures, the relative risk of serum creatinine elevation was 0.13 and the absolute risk reduction was 11.9 percent. Dopamine and diuretics have been shown to be ineffective in ameliorating the course of acute renal failure.
Predicting Prognosis in Patients with End-stage Liver Disease - Point-of-Care Guides
Proteinuria in Children - Article
ABSTRACT: Proteinuria is common in children and may represent a benign condition or a serious underlying renal disease or systemic disorder. Proteinuria may occur secondary to glomerular or tubular dysfunction. Although a 24-hour urine protein excretion test is usually recommended, it may be impractical in children. A spot, first-morning urine test for protein/creatinine ratio can be useful in this situation. Proteinuria is usually benign, in the form of transient or orthostatic proteinuria. Persistent proteinuria may be associated with more serious renal diseases. Clinical features from the history, physical examination, and laboratory tests help determine the cause of proteinuria. Treatment should be directed at the underlying cause. Patients with active urinary sediments, persistent and gross hematuria, hypertension, hypocomplementemia, renal insufficiency with depressed glomerular filtration rate, or signs and symptoms suggestive of vasculitic disease may require a renal biopsy and referral to a pediatric nephrologist.
Aminoglycosides: A Practical Review - Article
ABSTRACT: Aminoglycosides are potent bactericidal antibiotics that act by creating fissures in the outer membrane of the bacterial cell. They are particularly active against aerobic, gram-negative bacteria and act synergistically against certain gram-positive organisms. Gentamicin is the most commonly used aminoglycoside, but amikacin may be particularly effective against resistant organisms. Aminoglycosides are used in the treatment of severe infections of the abdomen and urinary tract, as well as bacteremia and endocarditis. They are also used for prophylaxis, especially against endocarditis. Resistance is rare but increasing in frequency. Avoiding prolonged use, volume depletion and concomitant administration of other potentially nephrotoxic agents decreases the risk of toxicity. Single daily dosing of aminoglycosides is possible because of their rapid concentration-dependent killing and post-antibiotic effect and has the potential for decreased toxicity. Single daily dosing of aminoglycosides appears to be safe, efficacious and cost effective. In certain clinical situations, such as patients with endocarditis or pediatric patients, traditional multiple dosing is still usually recommended.
ABSTRACT: Chronic kidney disease affects an estimated 27 million adults in the United States, and is associated with significantly increased risk of cardiovascular disease and stroke. Patients should be assessed annually to determine whether they are at increased risk of developing chronic kidney disease based on clinical and sociodemographic factors. Diabetes mellitus, hypertension, and older age are the primary risk factors that warrant screening. Other risk factors include cardiovascular disease, family history of chronic kidney disease, and ethnic and racial minority status. Serum creatinine levels can be used to estimate the glomerular filtration rate, and spot urine testing can detect proteinuria. After the diagnosis of chronic kidney disease is made, staging based on estimated glomerular filtration rate determines prognosis, evaluation, and management. Further evaluation should focus on the specific type of kidney disease and on identifying complications related to the disease stage. Patients should be assessed for risk factors leading to the further loss of kidney function and cardiovascular disease. Patients with estimated glomerular filtration rates less than 30 mL per minute per 1.73 m2, significant proteinuria, or rapid loss of kidney function should be referred to a nephrologist for further evaluation and management.