Diet for kidney patients
Patients with chronic kidney disease, a properly balanced nutrition play a vital role in maintaining the body health and preventing further kidney degeneration. In kidney disease, the body does not get rid of the waste and unwanted nutrients like toxic fluids, extra nutrients. These further buildup in the body and affect the kidney even more. Hence a change in the diet is a solution to keep the health of the kidney.
Depending on the intensity of the kidney disease, the principal component nutrients include protein, potassium, phosphorous, sodium and fluids.
1. Protein: principal function of the protein is to build and maintain bones, muscle, skin and hair. With the kidney disease, lower protein diet, he body condition worsened. Meats, seafood, eggs, legumes are good sources of protein. Seafood like shellfish, fish, and meat like beef, lean, lamb, pork, loin pork, turkey are the essential sources of protein.
2. Potassium: functions primarily for working of muscles and nerves. Any changes in the potassium level, affect the tonicity of muscles, hence their functioning. Hence a low potassium diet has to be maintained.
Apple, apricot nectar, cherries, cranberry juice, grapes, grapefruit juice, pear, lemon, lime, pineapple, plum, cabbage, corn, cucumber, onions, spinach, carrots, asparagus, alfalfa sprouts, lettuce, peppers are the fruits and vegetables giving less than 200 mg of potassium per serving.
For limiting potassium, these foods are to be eaten in a limit or avoided: banana, dried fruits, melon, mango, avocado, potatoes, broccoli, pumpkin, dried peas and beans.
3. Phosphorous: kidneys mainly control the balance of phosphorous in the body. When phosphorus is built up in the body, it removes calcium from the bones, leading to weakening of bones which break easily and cause severe pain. And too much phosphorous in the body, in the blood causes heart disease.
For a low phosphorous diet, milk substitutes like almond milk, rice milk, other supplements like angel food or cake, animal crackers, bun, cereals, cooked cereals except for oats, cookies of apple, berry, butter, popcorn, pita pocket.
To limit the phosphorous intake, boxed foods, cocoa, salad dressings, cheese(processed), light cream, soymilk.
4. Sodium: the primary and the most vital nutrient to be taken care of. The limit for sodium should be maintained, to prevent excess fluid from building in the body. When too much fluid is retained in the body, the blood pressure shoots up, suffer from breathlessness, and damage to the kidney and heart are observed.
Low sodium containing foods are bread, buns, rolls, desserts and pastries made from starch without much-added salts, fruits, meats without added sodium, homemade soups, vegetables without added salt.
The high sodium containing foods which should be prevented are boxed foods, cheese and cheese spreads, fast food, frozen dinners, soya and other Asian sauces, canned soups and vegetables.
5. Calcium: Calcium is another mineral component, calcium can affect kidney functioning, hence is limited by eating low-phosphorous containing foods. Phosphorus binders and high calcium content foods are to be avoided, as they deposit on the nephrons.
CHRONIC RENAL FAILURE
About chronic renal failure:
Kidney disease is a silent killer with no prominent signs of warning. In this disease the nephrons are severely affected, altering the normal functioning of the kidney. It affects the kidney functions like regulating of fluid and electrolyte balance, controlling blood pressure through the renin-angiotensin system, governing blood count through erythropoietin synthesis, directing parathyroid and skeletal function through phosphate elimination and activation of vitamin D.
The primary signs of renal failure are:
- High blood pressure
- Changes in the amount of urine passed and frequency of urination
- Alteration in the urine composition
- Presence of blood and pus cells in the urine
- Swelling of ankles and legs
- Loss of appetite and insomnia
- Shortness of breath, nausea, vomiting and severe itching
- Bad breath and metallic taste in the mouth
Chronic kidney damage is When the GFR rate is less than 60ml/min/1.73ml2 for more than 3 months or any other damage evidence for more than 3 months, calls for chronic kidney damage.
Kidney damage is of following types:
- Albuminuria
- Haematuria
- Pathological abnormalities
- Structural abnormalities.
Diagnosis of chronic renal disease:
- Tests for presence of albumin and blood in urine
- To check level of glomerular filtration rate and concentration of other waste products in the urine
- Blood pressure tests, as kidney disease results in development of higher blood pressure
- Ultrasound and CT scan to check any morphological abnormalities in the kidney and urinary tract, to locate tumours or kidney stones.
Results of the above tests determine :
- Glomerular filtration rate
- Albuminuria
- Creatine
- Urea composition
- Potassium
Stages of chronic renal failure:
The rate of nephron duration differs for every individual ranging from several months to years. This progression of renal failure occurs in primarily 4 stages: diminishes renal reserve, renal insufficiency, renal failure and end-stage kidney disease.
- Stage 1: normal GRR greater than or equal to 90 ml/min/1.73mI3
- Stage 2: slightly decreased GFR 60-89 ml/min/1.73mI3
- Stage 3a: mild-moderate decrease in GFR between 45-59 ml/min/1.73mI3
- Stage 3b: moderate-severe decrease in GFR between 30-44 ml/min/1.73mI3
- Stage 4: severe decrease in GFR between 15-29 ml/min/1.73mI3
- Stage 5: kidney failure as GFR decreases to less than 15 ml/min/1.73mI3 or dialysis is started.
Patients at risk of chronic renal failure:
- High blood pressure
- Chronic Diabetes
- History of heart problems like heart attack, failure or stroke
- Genetic history of renal failure
- Obese patients (BMI>30)
- Chain smokers
- Previous episode of acute kidney injury
Treatment :
- Blockade of renin-angiotensin-aldosterone system with angiotensin-converting enzyme inhibitors or an angiotensin receptor blocker is the primary treatment to prevent progression of the disease
- Blood pressure control (<140/90), reduces the renal disease progression and cardiology morbidity and mortality
- Optimal management of comorbid diabetes and cardiovascular diseases
- Monitoring of other related complications like anaemia, electrolyte abnormalities, irregular fluid balance, mineral bone disease and malnutrition
- Dialyses like haemodialysis and periodontal dialysis or final kidney transplantation
Kidney function test
The kidney is the vital organ of our body. It helps in the filtration and clearance of all the waste from our body. It also helps in elimination of filtered residues in the body. The kidney is constantly in a phase of filtration and elimination of minerals, toxins and other process residues from the blood and in turn, create urine. Hence any kidney absorbability is tested for urine and blood. Presence of blood or pus cells in the urine is an indication that the renal tubules might be damaged. Excessive use of drugs increases the load on the kidney, thus reducing the clearance rate.
Following are some tests mentioned which help in the complete analysis of the kidney functions.
BLOOD TESTS
- Serum creatinine: Creatinine is a waste product produced from the normal functioning of the muscles. A creatinine level higher than 1.2 for women and 1.4 for men is a sign of kidney in-functionality. As the kidney is more damaged, the level rises. Patients having the meal with meats, have the higher protein content, the level may rise.
- Glomerular Filtration Rate(GFR): measures the rate at which kidneys eliminate waste from the body and excessive fluid from the blood. GFR value less than 60, is a sign of reduction in kidney functionality. If it goes below 15, the kidney is probably in the last test of disease, needs immediate treatment.
- Blood Urea Nitrogen(BUN): as nitrogen is a breakdown product from protein foods, it is essential for us to know the concentration in the blood. The normal range is n7-20. As the kidney starts failing, the BUN values increases, meaning the kidney is not able to eliminate nitrogen from the body.
IMAGING TESTS
- Ultrasound: used for checking atrophy or any size-related anomalies in the kidney. Majorly due to damage or traumatic effect.
- CT Scan: checks for any structural abnormalities, like obstructions caused or any tissue damage. This is related to the disease associated with the kidney.
KIDNEY BIOPSY
- Done for many reasons like for identification of specific disease stages and check the treatment response
- Check the anatomical damage occurred to the nephrons
- To check the kidney after transplant for any resistance developed n the recipient’s body
URINE TESTS
- Urinalysis: done by dipstick, it changes colours according to the presence of abnormalities like the excess amount of protein, pus, bacteria and sugar. The presence of pus may be due to damage to the bladder, urinary tract. Other infections like chronic kidney disease, diabetes can be detected.
- Urine protein: to check the excess amount of protein present in the urine. It is a quantitative measurement done to also check the albumin-to –creatine ratio.
- Microalbuminuria: the higher level of dipstick test, used for detecting small amounts of albumin protein in the urine. Done by patients who are at a higher risk of developing chronic diseases like diabetes or blood pressure
- Creatine clearance: measures the clearance rate of the kidney and wastes eliminated per minute.
