Kidneys, renal diseases

Accessory Organs

Renal Diseases (kidney)

I Nephrotic Syndrome
A. cluster of symptoms which result in protein in the urine (albuminuria)
B. Consequences:
1. protein calorie malnutrition
2. anemia
3. infection
4. atherosclerosis: for unknown reasons blood lipid levels rise (CHO) and atherosclerosis develops as a result.
C. Medical Nutrition Therapy
1. adequate non-protein calories: leaves protein to do its own work, and not provide energy. Let carbs and fats provide energy.
a. normal protein intake (0.8 – 1.0 gm/kg)
2. low saturated fat/low CHO b/c of atherosclerosis
3. sodium restriction (~2 grams)

II Renal Failure
A. loss of the kidney’s ability to function
1. may be acute or chronic
B. Consequences
1. uremia (azotmeia): accumulation of waste products in the blood
2. electrolyte imbalance (hyperkalemia) (K+ is potassium)
3. changes in fluid balance
C. Medical Nutrition Therapy
1. Consider:
a. energy needs (non-protein kcals, don’t want to lose muscle weight)
b. protein restriction: depending on kidney function
c. electrolyte restriction: sodium, potassium, phosphorus (phosphorus should just be monitored, not restricted, b/c we have meds to lower)
d. fluid restriction: monitor intake and output
e. supplements: Ca, folate, B6, D

III Renal Calculi: kidney stones
A. calcium stones (75%)
1. causes:
a. hypercalciuria (idiopathic, unknown reasons...some people just excrete alot of Ca+ in their urine)
b. immobilization: hard/full body casts. When bones aren’t moving Ca+ leaves bones and is excreted through urine.
c. hyperoxaluria: oxalate binds to Ca+ and makes it unavailable. Diets high in oxalates bind with Ca+ and form a stone. (Ca+ is a cation and must have something to bind with, it choose oxalate)
2. medical nutrition therapy
a. Ca+ management
b. increased fluids to dilute urine
c. limit oxalate intake
B. Uric acid (10%)
1. common in gout where uric acid is distributed to distal joints
2. medical nutrition therapy
a. low purine diet: certain types of proteins break down into purines. Purines = uric acid. Rich proteins are caviar, sardines, red meat, liver, anchovies
b. increase fluids
C. Cystine (2-3%)
1. genetically linked
2. medical nutrition therapy
a. low methioninie diet (essential amino acid used to produce non-essential cystine)
b. increased fluids