Chronic Kidney Disease CKD

Definition of Chronic Kidney Disease Kidney Damage for ≥ 3 months as defined by structural or functional abnormalities of the kidney with or without decreased GFR: blood, urine, imaging, or pathological abnormalities.

Definition of Chronic Kidney Disease GFR ≤ 60 ml/min/ 1.73 m² for ≥ 3 months, with or without damage.

Stages of Chronic Kidney Disease Stage 1 CKD GFR is > 90 mL/ min Stage 2 CKD GFR is 60-89 mL/min Stage 3 CKD GFR is 30-59 mL/min Stage 4 CKD GFR is 15-29 mL/min Stage 5 CKD GFR is < 15 mL/min

Etiology of Chronic Kidney Disease Diabetes 46% HTN 28% Glomerular disorders 8% Underlying renal disease all other causes 18% Automimmune disease Polycystic kidney disease Other Infections Obstructive uropathy Interstitial disorders

Risk Factors for Chronic Kidney Disease Diabetes HTN Age Family history of kidney disease or diabetes Male gender

Risk Factors for Chronic Kidney Disease cont.. Racial ethnic background African American Native American Asian American Pacific Islander Latin American Tobacco use

Risk Factors for Chronic Kidney Disease cont.. Coexisting kidney disease Anemia High protein diet (controversial) Hyperlipidemia

Risk Factors for Chronic Kidney Disease cont.. Atherosclerosis Obesity Exposure to nephrotoxic drugs NSAIDS Contrast Dye Hydrocarbons

Recommended Screening Tests for Chronic Kidney Disease Serum Creatinine Blood Pressure Glucose Urinalysis Microalbuminuria/Proteinuria

Evaluation of Chronic Kidney Disease Laboratory testing Serum creatinine should NOT be used alone to assess kidney function Level of GFR is most accurate predictor Utilize prediction equations, such as MDRD and Cockroft-Gault to calculate GFR

Urinalysis Abnormalities of urine sediment RBC and RBC casts WBC and WBC casts Tubular cells Cellular casts Granular casts Fats

Microalbuminuria/Proteinuria Albumin excretion above the normal range (> 30 mg/24 hrs) Increased excretion of albumin is a more sensitive marker for Chronic Kidney Disease secondary to diabetes, glomerular disease and hypertension than proteinuria

Protein/Creatinine Ratio Collection of timed urine sample is inaccurate and inconvenient Spot urine protein to creatinine ratio provides an accurate estimate of urinary protein excretion rate and is unaffected by hydration state Normal < 200 mg/dl

Proteinuria Detection allows identification of CKD in asymptomatic individuals Key finding in the differential diagnosis of type of CKD Key prognostic indicator (increasing level) is associated with greater loss of kidney function

Proteinuria Beneficial therapy to reduce proteinuria ACE inhibitors and ARBs lower glomerular capillary pressure and decrease protein filtration, conferring a “reno-protective” effect on the kidney First choice in individuals with diabetes and may be used in non-diabetics with or without proteinuria

Radiographic Studios Ultrasound General appearance, increased echogenicity , size disparities and scarring, doppler interrogation

Radiographic Studios cont.. Intravenous pyelography (IVP) Risk from use of iodinated dyes, used infrequently

Radiographic Studios cont.. CT Obstruction, tumors, cysts, ureteral calculi CT with contrast may show renal artery stenosis MRI Renal vein thrombosis, mass lesions MR angiography with gadolinium to preserve renal function

Nuclear Scan Symmetry of kidney size or function, RAS, acute pyelonephritis, or scarring

Renal Biopsy Invasive procedure to determine the nature and extent of kidney disease Provides information on the diagnosis

Renal Biopsy cont.. May guide the treatment of kidney disease Provide prognosis information

Management of CKD Stages 1 and 2 B/P control Goal 130/80 or 125/75 with proteinuria Diabetes control A1C hemoglobin goal < 7.0

Management of CKD Stages 1 and 2 cont.. Use of ACE I or ARB Reduce proteinuria Avoid nephrotoxins

Blood Pressure Control B/P Goal <130/80 or < 125/75 with proteinuria Therapeutic Lifestyle Changes, such as: Weight loss Smoking cessation Dietary counseling Exercise

Blood Pressure Control cont.. Indications for use of ACEI or ARB Diabetic kidney disease Non-diabetic kidney disease with spot urine protein/creatinine ratio > 500-1000mg/g ACEI & ARB’s can be used as alternatives to each other or in conbination to lower B/P and reduce proteinuria

Monitoring Therapy Monitor for: Hypotension Decreased GFR Hyperkalemia May continue if serum potassium is < 5.5 or decline of GFR < 30% in 4 months

Glycemic Control Intensive glycemic control has been shown to slow progression of CKD ADA recommendation Hgb A1C < 7.0% FPG < 120 mg/dl

Glycemic Control cont.. Routine annual testing for microalbuminuria and serum creatinine to determine GFR Early intervention with ACE or ARB with microalbuminuria Pt at risk to develop hypoglycemia due to prolonged half life of insulin in circulation

Lipid Control CKD is a CHD risk equivalent LDL goal < 100

Timely Referral to Nephrology Referral indications Uncontrolled HTN on numerous agents Proteinuria > 1Gm/24 hr Estimated GFR < 60 ml/min

Early Intervention When creatinine level reaches 1.5 to 2.0 mg/dl most patients have lost more than one half of their GFR

Stage 3 GFR 59 - 30 ml/min Evaluate and treat complications Slow Progression

Anemia Management Iron replacement if ferritin less than 300 or percent of transferrin saturation less than 20% Oral iron IV iron Administer Erythropoiten

Bone Disease and Disorders of Calcium and Phosphorous Metabolism Osteitis fibrosa cystica: most common in CKD, associated with high PTH levels Adynamic bone disease: associated with low or normal PTH levels

Bone Disease High serum phosphorus: Low phosphorus diet Phosphate binders: Calcium carbonate or Sevalamer

Metabolic Acidosis Acid base disorder characterized by a fall in serum bicarbonate concentration

Metabolic Acidosis Failure to treat may: Decrease bone mineralization Increase protein catabolism Management Sodium bicarbonate treatment

Volume Overload Edema Shortness of breath, DOE, PND, Orthopnea CHF HTN

Volume Overload Management: Fluid restriction Diuretics DC medications that may contribute to sodium and water retention

Hyperkalemia Increases in serum potassium level and generally more prevalent in later stages of CKD Assessment: Elevated serum potassium level EKG changes Muscle weakness

Hyperkalemia Management Low K + Diet Careful use of medications (ACEI & ARBS and aldosterone inhibitors) that may contribute to hyperkalemia Sodium polystyrene Dialysis if indicated

Stage 4 GFR 29 - 15 ml/min Treat complications Prepare for renal replacement therapy

Management of CKD Taking care of the BEANS B = Blood pressure E = EPO A = Access for long term dialysis N = Nutritional care S = Specialist referral

B = Blood Pressure Control ACEI or ARB < 130/80 HTN exacerbates the vascular complications of diabetes DM plus HTN have 5-6 fold higher risk of developing CKD 6 than HTN alone

E = Erythropoietin Higher HCT improves LVH and CHF When Hgb < 10 or HCT < 30 Check Fe, TIBC, Ferritin Check stools for occult blood Improved Hgb leads to improved energy levels and ability to work

A = Access Ideally-early creation of simple AV fistula with 3-6 months to mature Avoid subclavian catheters secondary to subclavian stenosis

A = Access cont.. Create AV fistula when serum creatinine is greater than 4 or GFR < 20 ml/min Synthetic AV grafts inserted can be uses 2-4 weeks after placement CAPD catheters inserted 3-4 weeks before use

N = Nutrition Malnutrition in CKD 5 extremely common Albumin is marker of nutrition 2 year mortality > 3.0 g/dl = 20-30% 2 year mortality < 3.0 g/dl = 30-40%

N = Nutrition cont.. Uremic anorexia often causes spontaneous protein restriction Folate Avoid vitamins A,C, titrate D3 carefully

N = Nutrition cont.. Phosphorus should be kept at level between 3.5 and 5.0 Use calcium acetate or calcium carbonate Renagel, Lanthanum Sensipar Ideally dietary PO4 less than or equal to 1 Gm/day

S = Specialist Referral Acute GN, nephrosis-see Nephrologist ASAP See Nephrology GFR < 30 Serum creatinine 3.0 or more

S = Specialist Referral cont.. Gateway to Early dialysis access Renal Dietician Renal Social Worker RN Educators Continuation and nurture of primary care-patient relationship after dialysis begins