Definitions

What are renal calculi? What diet would be ordered for a patient with this condition? Is this similar to or different from the recommendations for end- stage renal failure?

Renal calculi are kidney stones. Kidney stones are hard deposits of minerals and acid salts that stick together in concentrated urine.

The diet recommendation depends on the kind of stone and the severity. For example, person with an oxalate or calcium stone would need to follow an oxalate free diet. This is different from the diet recommendations for end-stage renal failure. However, if the stone is severe enough that this person needs dialysis for a time, then the diet recommendations while on dialysis would be the same as someone with end-stage renal failure on dialysis. However, no matter what there is one big difference – the person with kidney stones needs to drink plenty of fluids to help the stone pass; a patient with ESRF on dialysis needs to limit their fluid intake.

What is nephrotic syndrome? What diet would be ordered for a patient with this condition? Is this similar to or different from the recommendations for end-stage renal failure?

Nephrotic syndrome is a type of kidney disorder in which your body excretes too much protein in your urine, and this is caused by damage to the clusters of small blood vessels in the kidneys that filter waste and excess water from the blood.

A patient with nephrotic syndrome would need to limit protein (0.8 g/kg) and sodium. They would also need to limit their fluid and saturated fat intake. These are the same dietary recommendations as stage 4 kidney disease, but not the same as stage 5 (which would be someone on dialysis).

How is “dry” weightof a patient on dialysis determined? What dietary factor would be impacted the most by a patient’s daily weight versus dry weight?

Liters of Actual Body Water = 142 mEq/L x Liters of Normal Total Body Water /Pre-dialysis serum sodium (mEq/L)

142 mEq/L = “normal” state of hydration

Normal Total Body Water = calculated by multiplying the patient’s pre-dialysis weight by the average percentage of body water for males (60%) and females (50%). A lower value (males – 57% and females – 47%) should be used in muscle-wasted or overweight dialysis patients

Dry Weight = Pre-dialysis weight – Liters of Actual Body Water

Fluid would have the greatest influence on a patient’s daily weight, sodium would be the second greatest influence.

Pathophysiology

Besides diabetes, what are some common causes of renal failure?

Risk factors for renal failure that can be modified include hypertension, dyslipidemia, albuminuria, cardiovascular disease, and obesity. Risk factors that cannot be modified include being over the age of 60, ethnicity, gender, and family history

Describe the clinical symptoms of a patient with chronic renal failure.

Symptoms develop over time if kidney damage progresses slowly. The signs and symptoms are nonspecific, and because the kidneys are able to adapt and compensate for loss of function, these may not appear until irreversible damage has occurred. Symptoms may include:

• Nausea
• Vomiting
• Loss of appetite
• Fatigue and weakness
• Muscle twitches and cramps
• Sleep problems
• Changes in frequency of urination (need to urinate more, especially at night)
• Trouble concentration
• Swelling of feet and ankles
• Persistent itching (dry, itchy skin)
• Puffiness around your eyes, especially in the morning
• Chest pain, if fluid builds up around the linings of the heart
• Shortness of breath, if fluid builds up in the lungs
• High blood pressure (hypertension) that’s difficult to control

Indicate normal values for healthy individuals and accepted values for dialysis patients for each of the following:

• BUN
• Creatinine
• K+
• Ca++
• Phosphorous
• Hematocrit
• Hemoglobin
• Triglycerides

	BUN	Creatinine	K+	Ca++	Phosphorous	Hematocrit	Hemoglobin	Triglycerides (dialysis: usually non-fasting)
Normal Values for healthy individuals	10-20 mg/dL	0.7-1.3 mg/dL	3.5-5.0 mEq/L	9.0-10.5 mg/dL	3.0-4.5 mg/dL	41-51 % male 36-47 % female	14-17 g/dL male 12-16 g/dL female	<250 mg/dL
Accepted Values for dialysis patients	Variable. May range between 60-80 mg/dL in patients who are anuric, well dialyzed, and eating adequate protein	2-15 mg/dL (based on muscle mass, GFR/dialysis)	WNL 3.5-6.0 mEq/L (predialysis)	WNL (Avoid sustained >10.2 mg/dL)	KDIGO recommendation: CKD Stage 3-5: WNL CKD Stage 5D: lower toward normal range	Targets based on 3x Hgb	~ 9-11 g/dL Variable based on patient needs, symptoms, risks. FDA <11 g/dL	<500 mg/dL KDOQI

Drug Therapy

Briefly discuss the use of the following drugs. Include classification, indication and contraindication for use with the renal patient, effect of the drug on nutrient absorption and utilization, effect of nutrients on drug absorption and utilization. (You may wish to put these in the form of a table or chart.)

	Prednisone	Kayexalate	Phos-Lo	Solumedrol	Erythropoietin (EPO)	Oscal
Classification	Corticosteroid	Cation-exchange resins	Phosphate binder	Steroid	Growth Factor	Calcium Supplement
Indication for use with the renal patient	Can help avoid organ rejection after a kidney transplant; it can also be used to manage other kidney disorders that can lead to nephrotic syndrome	Hyperkalemia	Used to reduce serum phosphorus in patients with end stage renal disease (ESRD)	Kidney transplant	Anemia secondary to chronic kidney disease	Osteomalacia
Contraindication for use with the renal patient	End stage renal disease	N/A	Hypercalcemia	End stage renal disease	Anemia	Hypercalcemia, kidney stones
Effect of the drug on nutrient absorption and utilization	Interfere with absorption of calcium, potassium, and vitamins C and D Interfere with excretion of sodium Increased catabolism of protein and decreased synthesis	Increased potassium excretion	Can cause increased blood calcium levels so avoid taking calcium supplements; Decreased iron absorption	Need to increase protein and calcium intake and limit caffeine and sodium	Stimulates RBC production	Iron and zinc need to be taken separately
Effect of nutrients on drug absorption and utilization	N/A	N/A	N/A	N/A	N/A	Vitamin D increases absorption; needs to be taken with meals

 

Nutritional Management

Define high biological value protein and discuss the rationale for its use with renal patients.
List 5 foods that contain high biological value protein.

A food is considered to be a high biological value proteinfood when it contains all nine essential amino acids.

If you are in the pre-dialysis stageof chronic kidney disease, then you need to restrict your protein intake, therefore it is recommended to avoid animal-based foods because they are rich in protein, and they seem to accelerate the progression of CKD more than plant proteins. Regardless, you still need all of the essential amino acids in your diet. You can achieve this by combining foods that balance each other out (meaning one food offers a certain set of amino acids, and the other food offers the rest), and this will provide you with the HBV protein you need.

Patients on dialysishave higher protein needs because protein gets lost during the dialysis process, so milk and dairy products, eggs and meats should be chosen as protein sources. If a patient on dialysis is not consuming enough HBV protein daily they are at an increased risk of developing protein-energy-malnutrition.

Five foods that contain HBV protein:

1. Lean meat
2. Poultry
3. Eggs
4. Milk and milk products
5. Fish and seafood

Describe the clinical rationale for a protein restricted diet for a patient with renal failure not on dialysis.

Excess protein damages the nephrons in the kidneys and thus accelerate the progression of CKD. In order to avoid helping accelerate this disease, dietary treatment is to decrease protein intake to help relieve the kidneys as much as possible.

Discuss vitamin/mineral supplementation appropriate for the renal patient on hemodialysis.

Vitamins always included: C, B1, B2, Niacin, B6, B12, Folic acid, B5, and Biotin

Vitamins sometimes included: E and D3

Minerals sometimes included: Selenium, iron, zinc

Dialysis patients need to get the water-soluble vitamins from a multivitamin because a lot get lost during the dialysis process, so it is important to replenish them.

Fat soluble vitamins are not removed through dialysis and may accumulate in the body and so are excluded from renal multivitamins. However, some do contain vitamin E and D. Vitamin E and selenium have antioxidant properties and aid in maintaining a healthy heart and vascular system, and vitamin D deficiency is common amongst patients with dialysis so a renal multivitamin that contains vitamin D may be recommended by the patients’ doctor based on their lab results.

Zinc has antioxidant properties and is involved in normal taste sensitivity, and it plays a role in the immune system. The typical renal diet is deficient in zinc, so some renal vitamins contain zinc.

Iron deficiency is not uncommon amongst patients on dialysis, so if iron deficiency does occur a multi vitamin with iron may be needed.