Chronic Kidney Disease

when is world kidney day
08 March 2012
Progressive azotemia over months to years
Symptoms and signs of uremia when nearing end-stage disease
Hypertension in majority
Isosthenuria and broad, waxy casts in urinary sediment are common
Bilateral small kidneys on US (unless PKD)
Essentials of Diagnosis of Chronic Kidney Disease
`National Kidney Foundation (NKF) defines CKD as
Evidence of renal damage
Based on abnormal urinalysis [proteinuria, hematuria] or structural abnormalities found with US

GFR < 60 mL/min for 3 or more months!!!
if you don't look for kidney failure...
you aren't going to find it
GFR < ___ will exhibit clinical signs & symptoms
< 30 some can be as low as 15 before they present clinically
what is the normal (adult) GFR
100 - 120 ml/min
how os GFR controlled
control of blood flow by changing the diameter of the afferent and efferent arterioles
control of glomerular surface area via contraction or relaxtion of mesangial cells
How many stages of chronic kidney disease
1 GFR >90
2 GFR 60-89
3 GFR 30-59
4 GFR 15-29
5 GFR <15 or dialysis
what kidney situation is NOT associated with HTN
nephrotic syndrome
waxy casts in urinary sediment are common when there is
a problem in the DCT
what is the creatinine clearance formula
Ccr= (140-age) X weight (kg)/Pcr X 72
kidney damage w/normal GFR is seen at what GFR
>90 (Stage 1)
Dx & treat
treat comorbid conditions, slow progression, CVD risk reduction
Kidney damage w/mild decrease in GFR
60-89 (Stage 2)
moderate decrease in GFR
30-59 (stage 3)
evaluate and treat complications
severe decrease in GFR
15-29 (stage 4)
perparation for kidney replacement therapy
kidney failure
GFR < 15 or dialysis (Stage 5)
replacement if uremia present
diabetes mellitus, hypertension, coronary vascular disease, FHx of CKD, and age > 60 yrs
Most common risk factors for CKD
Major outcomes of CKD include
coronary vascular disease, progression to renal failure, and development of complications of impaired renal function, such as anemia, disorders of mineral metabolism, and secondary hyperparathyroidism
reduced clearance of certain solutes principally excreted by the kidney results in
their retention in the body fluids.
The solutes are end products of the metabolism of substances of exogenous origin (food) or endogenous origin (catabolism of tissue)
is CKD revesrible?
the only exception is getting a kidney transplant
Reduction in renal mass leads to hypertrophy of the remaining nephrons with hyperfiltration, and the glomerular filtration rate in these nephrons is transiently at ________ levels
placing a burden on remaining nephrons, leads to
progressive glomerular sclerosis and interstitial fibrosis, suggesting that hyperfiltration may worsen renal function
symptoms of CKD
develop slowly and are nonspecific
Patients may remain asymptomatic until renal failure is far-advanced:
(GFR < 10-15 ml/min)
Manifestations of CKD can include
include fatigue, malaise, weakness, pruritis
GI c/o anorexia, nausea & vomiting, metallic taste and hiccups are common
Neurologic problems of CKD include
irritability, difficulty concentrating, insomnia, and forgetfulness
other symptoms associated with CKD progression
Menstrual irregularities, infertility, and loss of libido are also common as condition progresses
Exam reveals
chronically ill-appearing patient
Look for possible underlying cause (DM, SLE)
Hypertension is common
Skin may be
yellow, with evidence of easy bruising. May have nail changes (Mee's lines)
Uremic fetor (fishy breath) may be present
Cardiopulmonary and mental status changes are
also frequently noted...CMDT
Dx made by
documenting elevations of BUN and serum creatinine concentrations
GFR...once < 60
refer to Nephrologist
Persistent proteinuria is suggestive of
CKD, regardless of GFR level
broad, waxy casts (evidence of LOSS of tubular concentrating ability)
May see
see anemia, metabolic acidosis, hyperphosphatemia, hypocalcemia, and hyperkalemia...with both acute and chronic renal failur
evaluation needed to differentiate between acute and chronic renal failure
Evidence of previously elevated BUN and creatinine, abnormal prior urinalysis, and stable but abnormal serum creatinine on successive days is most consistent with a chronic process
Finding of small echogenic kidneys ______ by US supports diagnosis of CKD/irreversible disease
Finding of small echogenic kidneys (<9 cm)
Radiological evidence of renal osteodystrophy is another helpful finding
Check phalanges of hands
Also check clavicles
Complications (of uremia)
Cardiovascular (over 50% of deaths in pts with ESRD)
Acid-base disorders (tendency to retain hydrogen ions)
Disorders of mineral metabolism
Endocrine disorders
________is most common complication of ESRD
HTN control with
weight loss and tobacco cessation
Salt intake reduced to 2g/day
Initial RX to control HTN include
ACE inhibitor or angiotensin II receptor blocker (ARB)
If serum potassium and GFR permit (recheck 1 week)
Goal blood pressure is
Goal blood pressure is <130/80 mm Hg; for those with proteinuria > 1-2 g/d, goal is < 125/75 mm Hg
BP Goal if pt has proteinuria
for those with proteinuria > 1-2 g/d, goal is < 125/75 mm Hg
Pericarditis may develop with
Cause believed to be retention of metabolic toxins
Symptoms include chest pain and fever. May have pulsus paradoxus and friction rub on exam
Pericarditis is an absolute indication for initiation of hemodialysis
_____ is an absolute indication for hemodialysis
Patients with ESRD tend toward a ___ cardiac output
CKD patients, especially those with DM, are more likely to die from
cardiovascular disease than to progress to ESRD/dialysis!
Do not focus only on the CKD...if you do, you are missing the boat
Screen for and treat the C/V Dz and other risk factors present
Potassium balance usually remains intact until
GFR < 10-20 mL/min
Tx of acute hyperkalemia involves
cardiac monitoring, IV calcium chloride or gluconate, insulin with glucose, bicarbonate, and sodium polystyrene sulfonate
Chronic hyperkalemia treated with
dietary potassium restriction/sodium polystyrene PRN
The resultant metabolic acidosis is primarily due to
loss of renal mass
Damaged kidneys are unable to excrete the ________of acid generated by metabolism of dietary proteins
1 mEq/kg/d
treatment for acid base d/o
Maintain serum bicarb level at > 20 mEq/L
Alkali supplements include sodium bicarb, calcium bicarb, sodium citrate
Keep pH > 7.20
Normochromic, normocytic
Due to decreased erythropoiesis and RBC survival
Many patients are also iron deficient
Recombinant erythropoietin (epoetin alfa) used in
patients whose hematocrits are < 33%
Some recommend start with iron supplement and then possibly add ESA (erythroproeitin stimulating agents..Procrit/Epogen)
main cause of coagulopathy
platelet dysfunction
Platelet counts only mildly decreased, but bleeding time is prolonged
Platelets show abnormal adhesiveness and aggregation
Patients may present with petechiae, purpura, and increased bleeding during surgery
CKD coagulopathy
Tx goal of pt w/coagulopathy
= Hematocrit increased to 30%
Dialysis improves bleeding time but doesn't normalize it
Uremic encephalopathy does not occur until GFR falls below
10-15 mL/min
Symptoms begin with difficulty concentrating and can progress to lethargy, confusion, and coma
Earlier initiation of dialysis may prevent peripheral neuropathies
Neuropathy found in 65% of patients on or nearing dialysis but not until GFR is 10% of normal
Disorders of calcium, phosphorus, and bone are referred to as
renal osteodystrophy
Most common disorder of mineral metabolism
is osteitis fibrosa cystica - the bony changes of secondary hyperparathyroidism...affecting 50% of patients nearing ESRD
Radiographically, lesions most prominent in phalanges and lateral ends of clavicles
Look for
subperiostial erosions
may cause bony pain, proximal muscle weakness, and spontaneous bone fractures
osteomalacia or adynamic bone disease
Tx of Disorders of mineral metabolism
may consist of dietary phosphorus restriction, oral phosphorus-binding agents such as calcium carbonate or Renogel, and vitamin D
Hyperparathyroidism treated with calcitriol or Sensipar
Circulating insulin levels are higher because
of decreased renal insulin clearance
Glucose intolerance can occur in chronic renal failure when GFR is
< 10-20 mL/min. This is mainly due to peripheral insulin resistance...
Decreased libido and erectile dysfunction are common
Men have decreased testosterone; women are often anovulatory
ACE/ARB to slow progression of
proteinuria and CVD
Potentiates hyperkalemia...repeat serum creatinine & potassium in one week!!!!
Maintain excellent diabetes control...keep HgA1C ___
Lower cholesterol...consider
statin agent
Avoid fluid overload. Use diuretics such as
Lasix PRN
Refer patients to CKD clinics for management.... Goal of CKD clinics is to
keep the patient OFF dialysis!
Tx (Consult early) to
Nephrology, Vascular/Gen Surgery
Malnutrition very common secondary to
anorexia, decreased intestinal absorption/digestion...
Every patient should be evaluated by dietician
Protein restriction...
In general, protein intake should not exceed 1 g/kg/d!
salt and water restriction
For the nondialysis patient approaching ESRD, 2 g/d of sodium is an initial recommendation
Once GFR has fallen below 10-20 mL/min, potassium intake should be limited to
< 60-70 mEq/d
Magnesium restriction
No magnesium-containing .....
laxatives or antacids
Dialysis should be started when patient has GFR of
10 mL/min or serum creatinine of 8 mg/dL
when should diabetics start dialysis
Diabetics should start when GFR reaches 15 mL/min or serum creatinine is 6 mg/dL
indications for dialysis include
Uremic symptoms such as pericarditis, encephalopathy, or coagulopathy
Fluid overload unresponsive to diuresis
Refractory hyperkalemia...>7
Severe metabolic acidosis (pH < 7.20)
Neurologic symptoms such as seizures or neuropathy
BUN > 100
what dialysis method is the main choice for US pts
Hemodialysis (choice for 90% of patients in US)
Vascular access accomplished by an a/v fistula (preferred) or prosthetic graft
Patients typically require hemodialysis ___ times per week...sessions
Patients typically require hemodialysis 3 times per week...sessions last 3-5 hrs each
Ensure patient undergoing hemodialysis getting regular labs to include
Peritoneal dialysis
The peritoneal membrane is the "dialyzer"
Semi-permeable membrane...waste products pass through, blood cells do not
most common type of peritoneaLl dialysis is
continuous ambulatory peritoneal dialysis (CAPD)
Patients exchange dialysate 4-6 times per day
Put fluid in...drain in 3-4 hrs...repeat...
Continuous cyclic peritoneal dialysis (CCPD) utilizes
a cycler machine to automatically perform exchanges at night
Most common PD complication
= peritonitis
Most common pathogen = S aureus
PD is used more commonly
outside the US
Many nephrologists believe 25-35% of pts should be on PD
when is someone placed on a kidney transplant list
not placed on list until GFR <15
Living donor is best option!
One year survival rate is approximately 98% and five year survival rate is ____
Expected remaining lifetime for the age group 55-64 is 22 years, whereas that of ESRD population is
5 years
CKD pts most common cause of death is
For those who require dialysis to sustain life, but decide against it, death ensues within
days to weeks
dialysis numbers
10% Dxed with ESRD
3-4 dialysis txs/week (4 is best)
150 dialysis txs/year
Two-thirds of kidney transplants come from
deceased donors
Overall...medical care of CKD focuses on delaying or halting progression of CKD
Tx underlying cause(s)
Tx hypertension and diabetes
Avoid nephrotoxins
Tx complications out for meds that are renally excreted. You will need to adjust dose in patients with renal failure!!!