1. Diet and Renal diseases
Dr. Reham Khresheh
20/09/2018

2. OBJECTIVES After studying this chapter, you should be able to:
Describe, in general terms, the work of the kidneys
Discuss common causes of renal disease
Explain why protein is restricted for renal clients
Explain why sodium and water are sometimes restricted for renal clients
Explain why potassium and phosphorus are sometimes restricted for renal clients
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3. Loss of renal function
profoundly affects metabolism, nutritional status, and nutritional requirements
Nutrients most affected are
Protein
Calcium
Phosphorus
vitamin D
fluid, sodium
potassium
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4. Uremic syndrome
a cluster of symptoms related to the retention of nitrogenous substances in the blood
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5. Uremic syndrome fatigue unpleasant nausea decreased mental acuity
muscle twitches
cramps
anorexia
unpleasant nausea
vomiting
diarrhea
itchy skin
gastritis
GI bleeding
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6. Pre-end stage renal disease
period of renal failure when renal function is impaired
dialysis or transplant is not yet required
also known as renal insufficiency
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7. End stage renal disease (ESRD)
severe stage of chronic renal failure (CRF)
requires life sustaining treatment with either dialysis or a kidney transplant
BUN may be as high as mg/dL
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8. NUTRITION THERAPY 1. Protein
Protein restriction is cornerstone of dietary treatment for pre-end stage, which helps preserve nephron function & potential to lessen renal workload and slow disease progression
Too much protein increase BUN & the symptoms of uremia
Too little protein results in body protein catabolism, which increases serum potassium & BUN level & protein malnutrition as evidenced by low albumin levels.
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9. NUTRITION THERAPY (cont’d)
Low albumin is a strong predicator of mortality in pts starting dialysis
The most severe level of protein restriction is for renal insufficiency without dialysis
Recommended daily intake of protein is g/kg
It is recommended that 60% of total protein be from high biologic sources such as eggs, milk, yogurt, cheese, meat, fish, poultry, soy (because they promote reuse of circulating nonessential amino acids for protein synthesis & by doing so minimize urea production)
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10. NUTRITION THERAPY (cont’d)
2. Calories
Adequate calories are needed to prevent weight loss & body protein catabolism. Taking in too few calories can have the same effect as eating too much protein: BUN levels rise because body proteins are broken down for energy
Daily intake is 35 cal/kg for adults who are not undergoing dialysis
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11. NUTRITION THERAPY (cont’d)
Pure sugar & pure fats are recommended for calories because they do not provide protein
Children with renal failure experience growth failure. Aggressive nutrition therapy is needed, calcium supplements, vitamin D & phosphate may be used to promote calcium uptake by the bones
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12. NUTRITION THERAPY (cont’d)
3. Sodium & fluid:
If the client does not have edema, hypertension or signs of CHF, increasing the sodium intake as tolerated may improve GFR
If blood pressure & serum sodium levels are normal & edema does not occur, fluid intake can be exceed 24-hour urine output by 500 ml(fluid deficit)
Typical fluid allowance range from 500 to 3000 ml/day
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13. NUTRITION THERAPY (cont’d)
4. Potassium
Most clients with renal insufficiency & those undergoing peritoneal dialysis do not need to restrict potassium intake
Potassium restriction of 2-3 g/day is recommended for hemodialysis clients with hyperkalemia
Clients who are taking potassium-wasting diuretics may need more potassium to avoid hypokalemia
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14. NUTRITION THERAPY (cont’d)
5. Phosphorus & Calcium:
The metabolism of calcium, phosphorus, & magnesium is altered, resulting in hyperphosphatemia, bone demineralization, bone pain, & calcification of soft tissue (eye, skin, heart, lungs, blood vessels)
Renal osteodystrophy may be prevented by the following measures:
limiting phosphorus intake
providing vitamin D supplements
providing calcium supplements
avoiding aluminum which may cause encephalopathy & osteodystrophy
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15. NUTRITION THERAPY (cont’d)
6. vitamins
Deficiency of water soluble may caused by inadequate intake related to anorexia or dietary restriction; altered metabolism related to uremia
Water soluble vitamins are recommended for both nondialyzed & dialyzed clients
Except for vitamin D, supplement of fat soluble vitamins is not necessary. Vitamin A supplement is contraindicated (toxic)
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16. NUTRITION THERAPY (cont’d)
7. Trace elements
Zinc supplements is recommended if a zinc deficiency is identified
Iron & human erythropoietin are used to treat anemia
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17. Strategies to promote dietary adherence
Encourage clients to weigh and measure foods
Emphasize what to eat rather than food restrictions
Encourage social support from family and friends
Foster client’s perception of success and confidence
Provide feedback on self-monitoring
Encourage client to try low protein breads, cereals, cookies, gelatin, and pastas
indicated whenever protein intake is restricted
ensure that the protein consumed will be used for specific protein functions, not for energy requirements
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18. Strategies to relieve thirst
Use ice or popsicles
Suck on hard candy or mints
Chew gum
Frequent mouth rinsing with refrigerated water
Control blood glucose levels, as appropriate
Try frozen grapes
Use small glasses instead of large ones
Apply petroleum jelly to the lips
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19. Impaired calcium metabolism
results with loss of renal function:
faulty vitamin D metabolism
impaired intestinal absorption
hyperphosphatemia
A high calcium intake from food is not achievable when phosphorus is restricted
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20. Dialysis dietary restrictions can be liberalized
high protein intake is recommended to compensate for protein lost through the dialysate
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21. Acute Renal Failure (ARF)
ARF represents an even greater nutritional challenge than CRF
Protein, sodium, potassium, phosphorus, and fluid are adjusted according to
lab data
use of dialysis
renal function
drug therapy
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22. Immunosuppressant therapy
Renal transplant patients alter diet to lessen side effects of immunosuppressant therapy
Steroids cause
hyperglycemia
sodium retention
weight gain
potassium depletion
loss of calcium from the bones
gastrointestinal upsets
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23. Dietary measures for treatment of clients on dialysis
35 – 50 kcal/kg/day to prevent protein catabolism
500 – ml fluid/day
2-3 mg/day potassium
100 mg folate
10 mg pyridoxine (vitamin B6)
100 mg ascorbic acid
RDA of other water soluble vitamins
15 mg iron
calcium supplement up to 1,200 mg/d
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24. UROLITHIASIS
the precipitation of insoluble crystals in the urine leads to the formation of the stones (calculi)
80% of stones contain calcium, composed of calcium oxalate
10% of stones composed of uric acid
Calculi may result from low urine volume
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25. UROLITHIASIS (cont’d)
Certain dietary factors are implicated in stone formation:
Animal protein: make the more acidic, which promote calcium excretion & inhibits calcium reabsorption. Also considered the major source of purine, the precursors of uric acid. High levels of uric acid make calcium oxalate less soluble, thereby increasing the risk of calcium stone formation
Sodium: because the body rids itself of excess sodium through the urine, the greater the sodium intake, the greater the level of urinary sodium. High urinary sodium increases urinary excretion of calcium & uric acid & increases calcium mobilization from bone
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26. UROLITHIASIS (cont’d)
Oxalates: certain foods are rich source of oxalates, including nuts, chocolates, dark green leafy vegetables, tomato sauce & jam. So restriction dietary oxalates reduce urinary oxalate levels but not prevent stone formation
Calcium: calcium intake from diary products may be associates with high urinary calcium levels & stone formation. Dietary calcium may bind with dietary oxalates in the intestines, forming an insoluble compound that the body cannot absorb.
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27. Nutrition Therapy Increase fluids intake & thereby dilute the urine
Daily fluid intake 2.5 – 3 L is recommended
Fluid intake should be increased in hot weather & exercise
Water should be consumed before bedtime because urine becomes more concentrated at night
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28. Nutrition Therapy (cont’d)
For clients with hypercalciuria:
Increase fluid intake to increase urine output to 2 L/day
Limit animal protein, & sodium to 2 g/d, & oxalate
Vitamin B6 supplements reduce oxalate formation
Avoid Vitamin C, because the body can synthesize oxalate from it
Maintain adequate calcium intake
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