NUTR 408 Exam 2 Study Guide

During which stage of chronic kidney disease does the National Kidney Foundation (NKF) recommend that a protein intake of 0.6 g/kg/day be initiated? a. For acute kidney injury b. When HD is started c. When the GFR falls below 25 mL/min d. Protein should never be as low as 0.6 g/kg/day.

ANS: C WHEN THE GFR FALLS BELOW 25 ML/MIN When the patient's GFR falls below 25 mL/min and she is not receiving dialysis treatment, the NKF recommends a restriction of protein of 0.9 g/kg/day. Protein intake should be increased to 1.2 g/kg/day when HD is initiated. Protein intake for AKI is variable and depends on the underlying cause.

Which of the following increases the excretion of urinary calcium and uric acid? a. Animal protein b. Carbohydrate c. Fat d. Increased water intake

Ans.: A ANIMAL PROTEIN High animal protein intake promotes the excretion of urinary calcium and uric acid, increasing the risk of development of calcium oxalate or uric acid stones. Carbohydrates contribute phytates to the diet, which have been observed to be associated with decreased kidney stone formation. Omega-3 fatty acids in fish oil supplements lower urinary calcium excretion, partly because of less arachidonic acid production, which can increase hypercalciuria. Increased fluid intake decreases the risk of stone formation.

Which of the following foods does NOT potentially increase the acidity of urine? a. Lemons b. Cranberries c. Chicken d. Spaghetti noodles

Ans.: A LEMONS Fruits and vegetables contribute alkaline "ash" to urine, increasing alkalinity. However, cranberries, plums, and prunes contain benzoic and quinic acids, which are excreted in the urine as hippuric acid, increasing urinary acidity. Animal protein foods such as meats, eggs, cheeses, and bread and grain products contribute the most acid ash.

Renal adaptions that permit "normal" function eventually fail, causing a progression toward ESRD because of: A. loss of nephrons B. Uremia C. Increases in BP D. Imbalances between glomerular and tubular functions

Ans.: A LOSS OF NEPHRONS As ESRD progresses, the GFR declines because of a continuing loss of nephrons. As nephron number decreases, there is less functional capacity within the kidney to filter blood and promote the excretion of metabolic end products. Uremia results from inability to excrete nitrogenous waste products. Blood pressure increases as both sodium and water are retained, contributing to an increased blood volume. The filtration and exchange activities that occur within the glomerulus and tubules of the nephron continue in the functioning nephrons, but as the number declines, the dependence upon fewer nephrons places increased stress and wear on those remaining, continuing to promote the decline in nephron number.

Which kidney condition is associated with hematuria? a. Nephritic syndrome b. Nephrotic syndrome c. Pyelonephritis d. Renal tubular acidosis

Ans.: A NEPHRITIC SYNDROME Nephritic syndrome is a condition of inflammation of the glomerulus, resulting in the loss of blood into the urine. Nephrotic syndrome is characterized by the loss of the glomerular barrier to protein, resulting in hypoalbuminemia. Pyelonephritis is a bacterial condition of the kidney. Renal tubular acidosis involves a defect in the ability of either the proximal or distal tubule's ability to handle bicarbonate.

The most common renal stones contain calcium precipitates of A. Oxalate B. Phosphate C. Phytate D. Struvite

Ans.: A OXALATE Oxalate stones account for 60% of recurrent stone formation. Calcium phosphate stones account for 10% of cases. Dietary phytate inhibits the crystallization of calcium oxalate and calcium phosphate. Struvite stones contain magnesium ammonium phosphate and carbonate apatite and are only formed in the presence of urease-containing bacteria. These only account for 5% to 10% of cases.

The rennin-angiotensin mechanism A. Regulates calcium and phosphorus balance B. Regulates blood pressure C. Is the first function of the kidney to deteriorate in AFI D. Is responsible for the production of EPO

Ans.: B REGULATES BLOOD PRESSURE The renin-angiotensin mechanism is a major control for blood pressure. It works in concert with vasopressin. which is secreted by the pituitary.

Which of the following guidelines should be followed by a patient who has a history of kidney stones? A. Decrease fluid intake to keep urine output to less than 1 L per day. B. Decrease intake of magnesium-containing antacids. C. Increase fluid intake to maintain urinary output at or above 2 L per day. D. Use sodium bicarbonate to alkalize urine

Ans.: C INCREASE FLUID INTAKE TO MAINTAIN URINARY OUTPUT AT OR ABOVE 2 L PER DAY Low urine volume is the most common abnormality noted with patients who develop kidney stones, and increasing fluid intake by 2 to 2.5 L per day will prevent stone formation. This helps by both increasing urine volume and decreasing renal solute load. Magnesium potassium citrate can decrease the development of renal stones. Acidity of urine contributes to stone formation.

At least how much protein should be provided by the diet of a patient who receives hemodialysis three times per week? A. 0.6 g/kg of body weight B. 1 g/kg of body weight C. 1.2 g/kg of body weight D. 1.5 g/kg of body weight

Ans.: C 1.2 G/KG OF BODY WEIGHT Dialysis processes promote protein loss, and therefore, daily protein intake needs to be increased to compensate for this. For patients on hemodialysis, the recommendation is to consume 1.2 g protein per kg of body weight. Patients using peritoneal dialysis should consume 1.2 to 1.5 g protein per kg of body weight.

Intake of which of the following nutrients is generally NOT decreased in the nutrition therapy of patients with ESRD? A. Sodium B. Phosphorous C. Calcium D. Potassium

Ans.: C CALCIUM Dietary calcium is usually not decreased to prevent the development of renal osteopenia. In ESRD, sodium, phosphorus, and potassium are all retained in the blood. Increases in blood phosphorus levels in relation to blood calcium levels can stimulate the release of parathyroid hormone. PTH promotes the resorption of calcium from bone to increase blood calcium levels in proportion to the phosphorus. The only time calcium may be restricted is in the case of a patient demonstrating hypercalcemia while taking calcium supplementation

The primary cause of anemia that presents in chronic renal failure is a. lack of heme and nonheme iron intake. b. loss of iron through the diseased kidney. c. deficiency of the hormone erythropoietin. d. loss of blood through dialysis.

Ans.: C DEFICIENCY OF THE HORMONE ERYTHROPOIETIN The kidneys produce the hormone erythropoietin, which is involved in the production of red blood cells. The anemia that results in kidney failure is because of a deficiency of EPO. Ensuring adequate dietary intake provides adequate iron for hemoglobin formation when synthetic EPO is given to patients with renal failure. The kidneys are not the primary route of iron excretion, so their failure does not promote iron loss. Dialysis involves minimal blood loss.

In children with CKD the primary goal of MNT is a. to control of hypertension. b. fluid balance. c. normal growth and development. d. adherence to protein restriction.

Ans.: C NORMAL GROWTH AND DEVELOPMENT Cyclosporine is an immunosuppressive medication that promotes hyperkalemia, hypertension, and hyperlipidemia. Because of the potential for excessive potassium levels, planning of diets should account for potassium intake. Sodium intake need not be restricted below levels recommended by the Dietary Guidelines. To obtain protein, lean sources should be used in the diet. Adequate intake of calcium by transplant patients is necessary because of the risk of osteopenia promoted by other immunosuppressive medications.

Which of the following can minimize the resorption effects of increased parathormone on bone calcium that occurs in renal disease? a. Eliminating carbonated beverages to decrease phosphates b. Using thiazide diuretics to eliminate calcium c. Supplementing calcium early in the disease d. Decreasing protein products high in phosphate

Ans.: C SUPPLEMENTATION OF CALCIUM EARLY IN THE DISEASE The supplementation of calcium early in kidney disease is provided to reduce the imbalances in serum calcium and serum phosphorus levels that occur. Parathormone secretion is stimulated by increased serum phosphorus levels. PTH promotes bone resorption to elevate serum calcium levels. Calcium supplementation can help increase serum calcium levels and prevent phosphorus absorption from the gut. This is preferred over the increase of calcium-containing foods such as dairy because these foods provide calcium but also phosphorus. Carbonated beverages increase urinary acidity and contribute to calcium excretion. Thiazide diuretics cause potassium losses

A reduction in which of the following parameters is the first alteration that leads to the development of chronic failure or end-stage renal disease? A. Blood Pressure B. Left Ventricle Ejection C. Blood Volume D. Glomerular Filtration Rate

Ans.: D GLOMERULAR FILTRATION RATE As chronic renal failure progresses, the glomerular filtration rate (GFR) decreases. The kidneys adapt to the decrease in GFR as a means of preserving function; however, in the long run, it results in an increased loss of nephrons. Blood pressure may be affected by these adaptations, but because blood pressure may be affected by heart and blood vessel function as well as water and electrolyte alterations, it is not specific to impaired kidney function. Left ventricular ejection reflects the strength and structure of the heart. Blood volume is not affected until the end stages of renal failure.

When acute kidney injury (AKI) is caused by hypertrophy of the prostate, the ARF is classified as _____ AKI. a. secondary b. prerenal c. intrinsic d. postrenal

Ans.: D POSTRENAL Benign prostatic hypertrophy is an example of postrenal acute renal failure as the cause of the AKI is obstructive in nature. Prerenal causes of AKI include dehydration and circulatory collapse that result in inadequate renal perfusion. AKI resulting from diseases within the renal parenchyma, such as glomerulonephritis, is considered to be intrinsic AKI. Most instances of AKI are secondary to some other disease or condition; however, this is not one of the classification categories.