Chronic Kidney Disease Flashcards
Chronic kidney disease is the presence of kidney damage for 3 months or more, usually detected as which lab value?
Urinary albumin greater than 30 mg/day
There are three characteristic “failures” in chronic kidney disease. These are?
- ) Excratory failure (accumlination of excess nitrogen)
- ) Regulatory failure (abnormal conservation or excretion of fluids and electrolytes)
- ) Biosynthetic failure (inadequate production of ammonia, Vit. D, or EPO
Measures the amount of plasma filtered across glomerular capilaries (mL/min)
GFR
A normal GFR is?
120 ml/min/1.73 m2
A product of muscle breakdown produced at a relatively constant rate
- freely filtered by glomeruli
- Minimal to no reabsorption
- 10% secretion
Creatinine
Overestimates GFR slightly
Creatinine
GFR declines with age, but creatinine tends not to change due to parallel decrease in?
Muscle mass
What is the Schwartz equation for estimating GFR in children ages 1 to 17?
eGFR = 0.413 x height
A cysteine protease produced by all cells that is completely filtered by the glomeruli
- New method for GFR calculation
- Not readily available
Cystatin C
The BUN to creatinine ratio is usually 10-15:1. This ratio is disproportionally increase in which 6 situations?
Volume depletion, GI bleeding, Corticosteroid use, High protein diet, Obstruction, or any catabolic state
BUN is disproportionally decreaed in which 3 situations?
Low protein diet, Liver disease, Malnutrition
Increased glomerular permeability to macromolecules and is a marker of kidney damage when persistently elevated
Proteinuria in CKD
Increased Urinary Albumin Excretion is a sensitive marker for CKD due to which three diseases?
DM, GN, and HTN
A history of prior abnormal renal function/progression is of utmost importance in the evaluation of?
-i.e. prior abnormal urinalyses to distinguish from AKI
CKD
In addition to prior history of kidney damage, two other important factors of evaluating CKD are?
GFR estimate (eGFR) and Albuminuria/Proteinuria
Ultrasound of kidneys in CKD typically shows?
Small and echogenic kidneys
What are 5 major laboratory findings in CKD?
Elevated BUN and creatinine, Anemia, Metabolic Acidosis, and Hypocalcemia/hyperphosphatemia
In CKD, we may see a urinary sediment containing red blood cells, leukocytes, and casts, which may indicate
GN, tubulointerstitial disease, vascular disease, or urologic disorders
In the progression of renal disease, we see endothelial damage in the form of detachment of
Glomerular epithelial cells
In the progression of renal disease, we see production of
Cytokines
This results in further nephron dropout setting up a cycle leading to
ESRD
In CKD, we want to reduce blood pressure to?
- ) Normal Case?
- ) With significant proteinuria?
- ) Less than 140/80
2. ) Less than 130/80
Have benefits beyond their degree of BP lowering and are more effective with low salt diet or addition of diuretics
ACE inhibitors
In type II DM with CKD, we especially want to treat with
ARBs
Is it recommended to use ACEi’s and ARBs?
NO
7-10 days following initiatin of ACEi or ARB, we need to check BMP for?
Creatinine, and K+
Inhibition of agiotension II (by use of ACE inhibitors) slows deterioration in CKD by?
-This decreases proteinuria
Decreasing intraglomerular hypertension and changing glomerular barrier size
The benefit of ACEi’s is mostly seen in patients with significant
Proteinuria
We want to recommend a low protein diet in CKD patients with GFR values of
Less than 30-60
May play a role in the hyperfilitration seen in recently giagnosed DM
IGF-1
In DM, we can prevent progression to CKD with?
-Prevents transition to macroalbuminuria
RAS inhibition
A major risk factor for long-term loss of kidney function is?
Acute Kidney Injury (AKI)
An episode of AKI increases risk of developing CKD
4x
Metabolic Acidosis is one thing that can cause CKD progression, we can slow this with
NaHCO3 suplementation
Normally, we filter about 25,000 mEq of Na per day and excrete about 100-150 mEq. So normal FENa is
Less than 1%
We need to excrete progressively larger fractions of filtered load to stay in balance on usual intake as
GFR decreases
In CKD, urine osmolarity may be fixed at
300 mOsm/kg
In CKD, we see an increase in stool excretion of
K+
K+, Na+, and Water restriction are all important in
CKD
In HYPERkalemia, we can stabilize cardiac conduction by treating with
Calcium Gluconate
In HYPERkalemia, we can help move K+ INTO cells, by treating with which three things?
Glucose and insulin, NEbuized albuterol, and HCO3-
We can also treat HYPERkalemia with cation exchange resins such as?
Kayexelate (Na+ polystyrene sulfonate), and Veltassa (patiromer)
Common in CKD when eGFR is less than 25ml/min
-Due to decreased ammonia excretion
Metabolic Acidosis
In patient’s with normal renal function, even a SLIGHT decrease in plasma HCO3- induces tubular cells to
Increase NH4 production and H+ secretion
For patient’s withg CKD, we need to maintain HCO3- in normal range using non K+ containing HCO3- cupplements or citrate salts such as
Bicitra or Shohl’s
In CKD, we can also see problems with bone and mineral metabolism due to
Hyperparathyroidism and renal osteodystrophy
A systemic disorder of mineral and bone metabolism due to CKD
Mineral bone disease
Characterized by abnormalities of Ca2+, phosphorus, PTH, Vit D, bone turnover, etc
Mineral bone disease
In serum of patients with Mineral Bone Disease, we will often see a
Lower serum Ca2+, Elevated serum PO4, and Elevated PTH
Secreted by osteocytes and promotes renal phosphate excretion
Fibroblast Growth Factor 23 (FGF 23)
Levels increased early in CKD, stimulated by elevated serum PO
FGF 23
Increases renal PO4 excretion, stimulates PTH, supresses 1,25 di(OH) Vit. D, diminishing PO4 absorption from intestine
FGF 23
What are the three major types of Mineral Bone Disease (MBD)?
Osteitis fibrosa cystica, Adynamic bone disease, Osteomalacia
Most common form of MBD due hyperparathyroidism and osteoclast simulating efects of PTH
-high turnover type
Osteitis fibrosa cystica
Characterized by low turnover, spontaneously low PTH procution or iatrogenic suppression
-Sometimes caused by aluminum toxicity
Adynamix bone disease
Lack of bone mineralization. In the past was associated with Al toxicity, hypovitaminosis D
Osteomalacia
Frequently asymptomatic, but may manifest as joint pain and stiffness, spontaneous tendon rupture, and predisposition to fracture
CKD MBD
We also see extra skeletal calcifications in
CKD MBD
With stage 3-5 CKD, our goals we want to:
- ) Correct?
- ) Control?
- ) 25OH Vit D deficiency
2. ) Control Phosphorus
We can treat with calcium carbonate and calcium acetate which are
Phosphate binders
Sevelamer carbonate; lanthanum carbonate; ferric
citrate (Auryxia); and sucoferric oxyhydroxide (Velphoro) are
Noncalcium phosphate binders
To help increase Vit. D, we can take which three things?
Calcitriol, Doxacaldiferol, and paricalcitol
Increases sensitivity of parathyroid calcium sensing receptor to suppressive effect of calcium
Cincacalet (ESRD)
Almost universal with severe CKD when creatinine is greater 2-3 mg/dl
Anemia
CKD anemia is classified as
Nomorchromic and normocytic
CKD anemia is multifactorial but the major component is decreased
EPO production
Binds to erythroid progenitors causing differentiation to erythrocytes
EPO
Impairs activity, nutrition, quality of life, and contributes to LVH, and high output CHF
Anemia
Pre-dialysis (mean hemoglobin 10.1), we can treat with
EPO stimulating agent
Worsened if hematocrit is raised too quickly
Hypertension
Our goal Hgb 10-12 g/dL because studies show that in CKD we have increased risk of stroke and higher CV with
Hgb above 13
Clinical manifestation of severe kidney failure characterized by accumulation of organic waste products normally cleared by the kidney
Uremia
The surrogate markers for uremia are
BUN/creatinine
We refer patient for transplant evaluation when GFR is
Less than 20
Nausea, anorexia, uncontrolled hyperkalemia, and uncontrolled volume overload are some indications for
Dialysis
What are 4 modalities for ESRD?
- ) Hemodialysis
- ) Peritoneal dialysis
- ) Conservation management
- ) Transplant
