What is nephrotic syndrome?
A condition marked by (1) the deficiency of albumin in the blood and (2) protein excretion in the urine due to altered permeability of the basement membranes
When protein is lost in the urine, what does this lead to?
-Puffiness or swelling (edema), often of the eyelids, feet and ankles and eventually the abdomen
If left untreated, what can nephrotic syndrome lead to?
Problems with breathing, eating and infections
Criteria for nephrotic syndrome?
- Urinary protein levels >3.5 grams per day
- Average loss of 6-8 g/dat
Causes of nephrotic syndrome?
- Usually unknown
- May be diabetes
- It is a primary glomerular disease
Symptoms and complication of nephrotic syndrome?
- Proteinuria
- Hypoalbuminemia
- Edema,weight gain
- Hyperlipidemia
- Sodium retention
- Hypocalcemia
- Low iron
- Loss of appetite
What may be elevated in nephrotic syndrome due to decreased clearance?
Pre-albumin
Recall that pre-albumin is high in CKD
What can impair renal function?
Elevated lipid levels, where there is elevated T-Chol, TG and LDL-C in nephrotic syndrome
Is HDL affected in nephrotic syndrome?
Reduced or unaffected
Why is there hyperlipidemia in nephrotic syndrome?
Due to increased lipid synthesis and decreased catabolism
What does the level of hyperlipidemia correlate with?
The extent of proteinuria
Complications with nephrotic syndrome?
- High total cholesterol and TG
- Malnutrition
- High BP
- AkI
- CKD
- Infections
What are the key nutritional goals in nephrotic syndrome?
1) Reduce proteinuria
2) Prevent negative N balance
3) Control hyperlipidemia
4) Minimize edema
5) Delay further progression of renal disease and atherosclerosis
Energy?
35 kcal/kg/day
Protein?
0.8-1.0 g/kg/day
Sodium?
1-2g/kg/day
Calcium?
1-1.5 g/kg
Fluid?
1-1.5L/day
What is nephrolithiasis?
Kidney stones or renal lithiasis
When does nephrolithiasis occur?
When calcium, oxalate, struvite, cystine, hydroxyapatite or uric acid in the urine are higher than normal amounts
Risk factors for nephrolithiasis?
- family hx
- Previous stone formation
- **Hypercalciuria (most frequent)
- Hyperoxaluria
- Low urine volume
Other causes of kidney stones?
-Gout, excessive intake of vitamin D, UIT, urinary tract blockages and low urine output
What is the normal 24 hr urinary calcium excretion in men?
> 300 mg/24 hr
What is the normal 24 hr urinary calcium excretion in women?
> 250 mg/24 hr
Pathophysiology of kidney stones?
Imbalance between solubility and precipitation of mineral salts within the urine
What are the factors that contribute to stone development?
- Abnormal urine flow, urine composition, and presence of renal calculi that cause retention of urine
- Hydration status, as it is linked to the volume of urine produces
- Urine pH
How can kidney stones be based?
- Most can pass with lots of fluids and pain meds
- Some may require a medical procedure
Medical procedure for kidney stones?
Extracorporeal Shock Wave lithotripsy is most common
What should we focus on in our nutritional assessment?
The factors which are related to the stone development
What is our nutritional diagnosis likely to be?
-Excessive mineral intake, inadequate fluid intake, or food and nutrition related knowledge deficit
Nutritional therapy for kidney stones?
- Increase fluid intake by 3L/day, divided into doses
- No need to avoid dairy (calcium)
- Avoid >200 mg/day of vitamin C
- Use of probiotics
Why should vitamin C be limited?
When we eliminate vitamin C through the urine, the vitamin C will become oxalate, which will compound this issue with crystal formation
Why should we use probiotics?
They will facilitate the breakdown of oxalate
Why is limiting calcium not recommended?
As it can be many minerals which will create the stones - we can evaluate where the crystals came from after the stone was passed - in the case that it was calcium and then the patient had another kidney stone, then maybe we would limit calcium
Which diets correlate with more acidic urine and increase risk of stone formation?
Diets higher in intake of animal proteins and low intakes of fruits and vegetables
->DASH diet has been shown to reduce kidney stones
Low urine output (<2L/day) MNT nutrition goal?
Promote ample and dilute urine output to prevent urine supersaturation
MNT strategies for Low urine volume?
-Increase fluid intake (>3L/day) and distribute throughout the day
Hypercalciuria (>250 mg/day) MNT nutrition goal?
- Promote renal calcium absorption
- Normalize bone retention if sub-optimal
- Normalize GI absorption if excessive
MNT strategies for Hypercalciuria and promoting renal calcium absorption?
- Reduce potential renal acid load
- Reduce NaCl and sodium
- Reduce refined CHOS
MNT strategies for normalizing bone retention and normalizing GI absorption?
Increase dietary fiber
Hyperoxaluria (>45 mg/day) MNT nutrition goal?
- Enhance GI binding potential for oxalate
- Reduce oxalate biosynthesis
- Normalize (reduce) oxalate absorption
- Enhance bacterial degradation potential
How can we enhance GI binding potential for oxalate?
- Increase calcium and magnesium intake with meals
- Reduce intake of high oxalate foods if dietary intake is high
How can we reduce oxalate biosynthesis?
- Try pyridoxine if enzyme dysregulation is suspected
- D/c ascorbic acid supplements if >200 mg/day
How can we reduce oxalate absorption?
Address fat malabsorption if it is a contributing factor
How can we enhance bacterial degradation potential?
- Initiate probiotic therapy
- Increase dietary prebiotics
Hyperuricosuria (>700 mg/day) MNT nutrition goals?
- Reduce uric acid biosynthesis
- Reduce uric acid precipitation load
How can we reduce uric acid biosynthesis?
-Decrease meat high in purines
Hypernatriuria (>200 mmol/day) MNT nutrition golas?
- Minimize calciuric effect of extra-cellular volume expansion
- Minimize efficacy of diuretic therapy
How can we treat hypernatriuria?
-Decrease NaCl and sodium intake to lowest levels possible
Low urine pH (<5.6) MNT nutrition goal?
Reduce crystallization potential for uric acid and cystein calciul
Strategies to combat low urine pH?
- Reduce potential acid renal load
- Address bicarb wasting
- Address obesity, diabetes
Examples of high oxalate foods?
- Beets
- Spinach
- Rhubarb
- Nuts
- Chocolate
- Dried beans
To reduce oxalate absorption, increase ____ and limit ___
- Calcium
- Vitamin C
The use of probiotics is to increase the _____ of oxalate in the GI tract
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