Chronic Kidney Disease Heidi Anderson Erica Bailey Anai Villalobos Katie Pearce
Anatomy of the Kidney 2 major parts: Cortex Medulla Functional Unit Nephrons Renal Pyramid Renal Pelvis Ureter
Nephrons
1.) Glomerular Filtration Fluids and solutes in the blood plasma of the glomerulus pass into the glomerular capsule (glomerular filtrate) Mechanisms to cause this fluid to be filtered is High hydrostatic pressure of the blood in the glomerulus Large number of pores Substances present in the glomerular filtrate: water, electrolytes, glucose, AA, urea, hormones, and vitamins. -exclude large molecules that are in the blood.
GFR The best way to measure levels of kidney function. GFR= urine volume x inulin conc. In urine inulin conc. In plasma (mg/ml) Best estimates of GFR: Inulin clearance Creatine clearance Plasma creatinine concentration Blood urea nitrogen (BUN)
2.) Tubular Reabsorption Trans-epithelial transport Most solutes reabsorped completely Urine volume is regulated by the needs of the body Active vs. Diffusion Tm
3.) Tubular Secretion Movement from the peritubular capillaries into the lumen of the tubule. Main Substances secreted H+ K+ Some organic anions
http://ccn.aacnjournals.org/cgi/content/full/26/4/17/f1
Functions of the Kidney Elimination of wastes, excess water and solutes, and conserves nutrients Acid-base balance Renin-angiotensin system Erythropoietin release Activation of Vitamin D
Elimination of Waste Kidney receives 20% of cardiac output, which allows the filtering of approximately 1600 L/day of blood. This is translated into 1.5 L of urine a day to be excreted, on average The fluid filtered from the blood plasma is modified and reabsorbed as it travels along the tubules. The remainder finds its way into the ureter, which carries the urine to the bladder from each kidney.
Acid-Base Balance Kidney is responsible for 2 major activities: Reabsorption of filtered bicarbonate Excretion of the fixed acids (acid anion and associated H+) Both of these processes involve secretion of H+ into the lumen by the renal tubule cells Only the 2 nd one leads to excretion of H+ from the body. Acidosis vs. Alkalosis
Renin- Angiotensin System Regulation Of Blood Pressure
Erythropoietin Release EPO is a hormone primarily produced by the kidney Occurs when a drop in blood oxygen level is perceived. Used to treat anemia. Glycosylated erythropoietin comes in 3 forms: alpha (the most commonly used type in veterinary medicine), beta (of similar clinical efficacy to alpha) Darbepoetin (which is particularly heavily glycosylated and lasts the longest).
Vitamin D Activation Parathyroid hormone is able to drive stored calcium and phosphorus from the bones as is vitamin D so these hormones are able to work in concert here but in the kidney they have different functions. In the kidney, while vitamin D saves both calcium and phosphate, parathyroid hormone causes only calcium to be saved and phophate to be dumped. There is a third hormone called calcitonin that keeps the blood calcium level from indefinitely rising. When blood calcium starts to get too high, calcitonin is released to begin storing calcium and phosphate back in the bones until it is needed again.
At Risk Populations Racial Groups: African Americans Native Americans Hispanics Pacific Islanders Risk Factors: Diabetes Hypertension Family history of kidney failure
Looking at Geographics
Hypertension
CKD
Genetics The angiotensinogen promotor G(-6) allele lowers transcription and is inversely associated with hypertension. the A1166C 3'-UTR variant of angiotensin II type 1 receptor (AT1R) has been associated with CKD. The AT1R C1166 allele may increase susceptibility but only in the presence of hypertension.
What is CKD? CKD is the gradual loss of the kidney s ability to filter waste and fluid from the bloodstream. Nephrons filter waste out of the blood. Nephrons become damaged and lose their filtering ability overtime. As more nephrons are damaged, the healthy ones work harder. Kidneys become scarred or may shrink in size.
Etiology Diabetes is the number one cause of kidney disease, responsible for about 40% of all kidney failure. High blood pressure is the second cause, responsible for about 25%. About 12.2% of Native Americans over the age of 19 have type 2 diabetes. Diabetes and high blood pressure are the leading causes of CKD.
Etiology-cont. Other causes include: - Glomerulonephritis (kidney inflammation) - Genetic diseases (i.e. polycystic kidney disease) - Autoimmune diseases (i.e. lupus) - Birth defects - Obstructions caused by problems like kidney stones or tumors
Pathophysiology As the renal tissue loses function, the remaining tissue increases its performance renal function interferes with the ability to maintain fluid and electrolyte homeostasis. ability to concentrate urine ability to excrete phosphate, acid and K creatinine and urea and GFR Heart failure can result from Na and water overload
Pathophysiology-cont. production of calcitriol leads to hypocalcemia osteopenia or osteomalacia. excretion of phosphate leads to hyperphosphatemia Secondary hyperparathyrodism is common renal osteodystrophy. Normochromic-normocytic anemia (Hct of 20-30%) caused by erythropoietin production due to functional renal mass.
Phosphorus Pathophysiology Decreased renal function Cacliphylaxis Decreased active vitamin D Increased blood phosphorus Increase blood calcium levels Increased blood PTH Decreased bone mass
Cacliphylaxis Deposition of calcium phosphate in soft tissues This occurs when the phosphorus-calcium product is too high (greater than 4.5 (mmol/l) 2 Cacliphylaxis is associated with CVD Calcium phosphate is deposited on heart valves and blood vessels
Diagnosis Based on laboratory testing of renal function: - Creatinine - GFR - BUN Urinalysis (check for protein, blood and WBC in urinewhich should not be there). Sometimes renal biopsy. MRI or ultrasound to check the size.
LABS Glomerular filtration rate (GFR) is the best measure of kidney function. A doctor will order a blood test to measure the serum creatinine level. As kidney function, blood levels of creatinine.
Creatinine It is a waste product that is passed through the kidneys. A by-product formed by muscle contractions. It also comes from protein foods we eat. creatinine may signal that the kidneys aren t eliminating this waste, leaving it in the body. Normal range: 0.8-1.4mg/dL
Glomerular Filtration Rate (GFR) Measures the kidney function and the stage of CKD. As the kidneys become more damaged, the GFR will decrease. Normal range: >90, with little or no protein or albumin in the urine.
Blood Urea Nitrogen (BUN) The BUN test measures the amount of urea in your bloodstream. Urea is a waste product left over from the protein we eat, which is normally eliminated through the kidneys. urea mean the kidneys are not getting rid of waste and it remains in the body. Normal range: 7-20 mg/dl
S/S CKD is a silent, but devastating disease. Azotemia Uremia urination (nocturia) Fatigue/weakness Nausea and vomiting Bruising/bleeding Uremic frost (crystals in and on skin)
S/S cont. Loss of appetite Edema in feet, ankles, hands, or face Back pain Itching Shortness of breath (fluid can build up I lungs) Ammonia breath or taste in the mouth
5 Stages of CKD Help doctors give the best treatment to patients Each stage requires different tests and treatments
Stage GFR Level Description Stage 1 90 ml/min or more Healthy kidneys or kidney damage with normal or high GFR Stage 2 60 to 89 ml/min Kidney damage and mild decrease in GFR Stage 3 30 to 59 ml/min Moderate decrease in GFR Stage 4 15 to 29 ml/min Severe decrease in GFR Stage 5 Less than 15 ml/min or on dialysis Kidney failure
Stage 1 GFR > 90 ml/min Kidney damage Normal or increased function No symptoms of damaged kidney People aren t usually diagnosed unless they are being tested for something else
Stage 2 GFR 60-89 ml/min Mild decrease in kidney function This GFR is normal for some people People with GFR >60 are still considered to have Chronic Kidney Disease if they have some kind of damage to their kidney
Stage 3 GFR 30-59 ml/min Moderate decrease in kidney function Uremia Symptoms may start to develop
Stage 4 GFR 15-29 ml/min Severe decrease in kidney function Patients will start thinking about dialysis or transplant Think about getting a fistula so it has time to mature
Stage 5 Less than 15 ml/min Kidney failure with treatment End stage renal disease Kidneys are unable to remove waste and fluid from the body
Complications of CKD Cardiovascular disease Anemia High blood pressure Bone disease
Can CKD be Halted or Reversed? Cannot be reversed No known cure (other than kidney transplant) Can be halted! Use preventative techniques to halt the progression.
Prevention Prevent and control high blood pressure Prevent and control diabetes Early diagnosis Routine physical examinations Stop smoking Decrease alcohol consumption
Hypertension Prevention/Control Most important thing to prevent of CKD Maintain Healthy weight Exercise to raise your heart rate Reduce Sodium in diet Take Medication Can slow rate of kidney damage by 50%!
Diabetes prevention Eat a healthy Diet Fiber, whole grains Fruits and vegetables Maintain normal blood glucose levels Exercise Obtain and maintain healthy weight
Prevention Programs National Kidney Foundation s KEEP Free screening Educational materials Designed to raise awareness Need a better global effort Require a lot of man power and funds
Diabetes and Birth Can lead to complications for the fetus as soon as the first 6-8 weeks of life CNS deformities Musculoskeletal deformities Congenital heart disease Spontaneous abortion Large birth weights Shoulder dystocia
Diabetes and Birth Large birth weight If diabetes is not controlled Baby gets high blood sugar Baby makes more insulin Stores the extra calories as fat overfed
Compliance with Diabetes treatments and development of CKD Study done showing that intensely treated diabetics were 21% less likely to have nephropathy. Patients who more tightly control their blood sugar are less likely to have renal complications The longer a patient is noncompliant with diabetes treatments, the greater risk he/she has of developing CKD.
Quality of Life Physical Function Social Activity Energy Cognition Emotion (anxiety, fear, denial, anger, depression, etc) Sleep patterns-sleep apnea Health Perception General Life Satisfaction
Life Expectancy Mortality increases as kidney function decreases. Leads to increased risk of CVD Life expectancy of a 40- to 44-year-old white male in the general population in the US is more than 35 years. Long Term Dialysis can add about 8 more years
Organizations/Support Groups Organizations National Kidney Foundation American Kidney Fund Support Groups Renal Support Network American Association of Kidney Patients
Medical Treatment There is no cure to CKD, but there are ways to slow the progression of the disease: Control blood glucose Insulin therapy Metformin Other diabetes medications
Medical Treatment cont. Control blood pressure ACE inhibitors ARBs Diuretics MNT Decrease protein intake Decrease phosphorus intake Phosphorus binders Decrease sodium intake
Effect of diet on progression For diabetic patients, management of their diabetes can prevent or decrease the progression of CKD. Managing blood pressure can also help to control the progression of CKD. Cochrane Database study found that lower protein diets reduced renal death by 32% in non diabetic adults
MNT Energy Protein Fluid Sodium Potassium Phosphorus 30-35 kcal/kg IBW 0.6-1.0 g/kg IBW Ad libitum Variable, 2-3 g/day Variable, usually ad libitum or increased to cover losses with diuretics 0.8-1.2 g/day or 8-12 mg/kg IBW
MNT--Protein Urine Output Percent HBV Protein Recommendations > 55 ml/min 60% 0.8 g/kg/day 25-55 ml/min 60% 0.8 g/kg/day <25 ml/min 50% 0.6 g/kg/day * *This can increase to 0.75 g/day if the patient cannot get 35 cal/kg IBW.
MNT Protein Excess protein in the diet Excess ammonia in the blood Increased stress on the kidney More rapid kidney failure
MDRD Study Kidney Failure Death Kidney Failure or Death Low protein diet (.58 g/kg/day) 90.7% 23.3% 96.1% Very low protein diet (.28 g/kg/day with.28 g/kg/day EAA) 87.3% 38.9% 95.2%
MNT Sodium Restriction of sodium to 2-3 grams/day. This may help decrease blood pressure. It may also decrease proteinuria.
MNT--potassium In stages I-IV CKD, potassium intake may need to be increased or decreased depending on the lab values for the specific patient. Fruits and vegetables are generally high in potassium. The potassium content can be decreased by soaking vegetables in water.
MNT--Phosphorus Phosphorus is normally excreted in the kidneys. In CKD, phosphorus can build up in the blood. Depending on lab values, it may be necessary to decrease dietary intake of phosphorus. High-Phosphorus Foods Dairy products Meat Nuts
MNT Vitamin D When serum active vitamin D is low, PTH is secreted. This causes increases in calcium and phosphorus which can lead to calciphylaxis. Vitamin D supplementation is still controversial.
MNT--Carbohydrates It is important for diabetic patients to manage their diabetes: Spread carbohydrates throughout the day. Eat at consistent times throughout the day.
Case Study--ET 24 YOF Pima Indian Dx with type 2 DM at 13 years old, poorly compliant GFR decreasing over the past year 1 + pitting generalized edema
Lab Values Parameter Normal Value Patient s Value Rationale Albumin 3.6-5.0 3.2 Albumin is being lost in the urine Osmolality 275-295 400 Glucose is high BUN 8-26 80 Indicates kidney dysfunction Creatinine 0.6-1.3 1.5 Indicates kidney dysfunction Cholesterol 140-199 443 High sat fat diet HDL 40-85 37 High sat fat diet LDL <130 132 High sat fat diet Triglyceride 35-160 300 High sat fat diet HbA 1 C 4.8-7.8 8.2 Glucose has been consistently too high
PES Statement Excessive fat intake relating to eating too many high fat foods as evidenced by 24 hour recall and high blood lipid levels (chol: 443 mg/dl, LDL: 132 mg/dl, TG: 300 mg/dl).
Sample Diet Pt weighs 63.6 kg Recommended amounts:.8 g protein/kg = 51 g 30-35 kcal/kg = 1908-2226 kcals 8-12 mg/kg phosphorus = 509-763 mg 3 g sodium restriction
Sample Diet Breakfast Apple juice Toast w/ butter Margarine Peach Rice krispies Milk Lunch - Taco: ground beef, tortilla, onion, tomato, lettuce - Grapes
Sample Diet Dinner Penne pasta Marinara Green beans Caesar salad Romaine lettuce, croutons, tomato, dressing Rolls with butter
Sample Diet Actual from Diet: Protein: 46 g Calories: 1954 kcals Phosphorus: 785 mg Sodium: 3111 mg