BCPS - Nephrology
Terms in this set (107)
AKIN criteria for AKI
W/in 48 hrs
1. Inc in Scr 0.3 mg/dL
2. Inc in Scr 50% x baseline
3. UOP 0.5 mL/kg/hr >6 hrs
1. Stage 1: Inc Scr>0.3 or 1.5-1.9 x baseline
2. Stage 2: Scr 2-2.9 x baseline
3. Stage 3:
a) Scr >/=3x baseline
b) Inc 0.5 in Scr >/=4
1. Kidney damage >3 months as shown by structural or functionality abnormality, w/ or w/o decrease in GFR
2. GFR<60 mL/min >3 months w/ or w/o damage
KDOQI CKD staging
Stage 1: damage w/ GFR>/=90
Stage 2: GFR 60-89
Stage 3: GFR 30-59
Stage 4: GFR 15-29
Stage 5: GFR <15
CKD Risk Factors
3. Autoimmune Dz
4. polycystic kidney dz
5. drug toxicity
CKD Progression Factors
2. Elevated BP
CKD: ACR values
1. Normal to mild <30
2. Moderately increased 30-300
3. Severely increased >300
CKD: value for nephrotic-range proteinuria
DM nephropathy: pathogenesis
1. HTN (systemic or intraglomerular)
2. Glycosylation of glomerular proteins
3. genetic links
DM nephropathy: Dx
1. Long hx of DM
3. Retinopathy (suggests microvascular dz)
DM nephropathy: BP goals according to different guidelines
1. ADA: <140/90
a) mild albuminuria = </=140/90
b) moderate to severe = </=130/80
3. JNC 8: <140/90
DM nephropathy: BP meds that should be used with any degree of proteinuria independent of HTN
ACEI or ARB
DM nephropathy: Diuretic typically used for CKD stages 1-3
DM nephropathy: Diuretic typically used for CKD stages 4-5
DM nephropathy: when to start a 2-drug combination for BP
2 complications with CKD
2. Renal osteodystrophy w/ hyperparathyroidism
CKD causes of Anemia
1. Dec EPO production
2. Dec RBC lifespan
3. blood loss thru HD
4. Iron deficiency
5. renal osteodystrophy
Anemia: initiate evaluation when?
1. CrCl<60 mL/min
2. Hb<10 g/dL
Anemia labs to monitor
1. RBC indices: MCV, Reticulocyte count
2. Iron studies: TSAT (Fe & TIBC) and Ferritin
3. Vit B12 & Folate
4. Stool guaiac
When is Anemia treated with ESA?
1. when Hb still <10 g/dL after iron therapy
Why is oral iron typically avoided in HD patients?
insufficient absorption relative to increased needs
ESA initial monitoring frequency?
every 2-4 weeks
ESA maintenance monitoring frequency?
non-HD: every 3 months
HD: at least monthly
ESA: dose adjustments are made in terms of what %?
ESA: goal Hb in HD pts?
ESA: goal Hb in non-HD pts?
ESA: ideally, how fast does Hb rise?
1 g/dL in 4 weeks
ESA: if Hb increases >1 g/dL in 2 weeks?
reduce dose 25%
ESA: if Hb increases less than 1 g/dL in 4 weeks?
increase dose 25%
ESA: use caution in patients with a hx of what?
stroke or cancer
ESA: 2 types
Darbepoetin alfa (less frequent dosing)
Several Causes of ESA Tx failure
1. Iron deficiency (most important)
4. aluminum toxicity
5. B12 or folate deficiency
7. Vit C deficiency
CKD: Ferritin goal levels
non-HD: >100 ng/mL
HD: >200 ng/mL
CKD: TSAT goal level
Empiric iron dosing for Anemia in CKD
1000 mg IV total cumulative dose
Renal osteodystrophy: contributing factors
2. dec production of active vit D
3. dec absorption of calcium in gut
4. dec ionized Ca
5. direct stimulation of PTH - leading to bone resorption
Renal osteodystrophy: signs and symptoms
2. musculoskeletal and GI pain
3. calcification on radiography
Renal osteodystrophy: alkaline phosphatase will generally be (elevated/decreased)?
Phosphate binder frequency
TID w/ meals
Phosphate binder DOC for stages 3-5
This calcium phosphate binder binds better w/ lower elemental Calcium
Phoslo (calcium acetate)
Phosphate binder DOC for stage 5
Consider these phosphate binders in hypercalcemia
2. Lanthanum carbonate
Vitamin D helps accomplish what 2 things?
1. suppress PTH
2. help Ca gut absorption
what is often a tx-limiting factor for Vit D/Vit D analogs?
Classification of vitamin D levels
1. insufficiency 16-30
2. mild 5-15
3. severe <5
This medication is the active form of 1,25-dihydroxyvitamin D3
Which Vit D/Vit D analog has highest incidence of hypercalcemia?
which Vit D/Vit D analogs require no renal OR hepatic activation?
Calcitriol and paracalcitol
this Vit D analog requires hepatic activation
which phosphate binder has shown superiority over the others in terms of clinical outcomes?
none have shown superiority over another
Calcimemetic that attaches to parathyroid gland and increases sensitivity to Ca
Cinacalcet initial dose
This medication is good for high Ca/PO4 levels + high PTH levels
what do you monitor and how frequently with cinacalet?
Serum Ca every 1-2 weeks
what PTH mechanism is lost when GFR drops below 30 mL/min?
the ability to decrease PO4 reabsorption and to increase Ca reabsorption
A - acidosis (refractory to bicarb/acetate)
E - electrolyte imbalance
I - intoxication of drugs
O - volume overload (pulmon. edema)
U - uremia (encephalopathy)
HD access with lowest complications
HD access often used in vascular dz or with small, weak veins
Tx for intradialytic hypotension
1. NS bolus
2. midodrine before HD
3. reduce ultrafiltration rate
4. trendelburg postition
True/False: antiplatelets can be beneficial for thrombosis prevention d/t HD
False: no efficacy has been shown
Most common infx bug in HD
Peritionitis in PD pts: what bugs need to be covered empirically?
Gram +: S. epi, S. aureus, strep
Gram - : E coli, pseudomonas
In treating peritonitis for PD, what route should Abx be administered?
Chronic interstitial nephritis causes?
when does chronic interstitial nephritis present d/t cyclosporine/tacrolimus?
what is the presentation of lithium-induced chronic interstitial nephritis?
usually asymptomatic. Slow inc in BP or BUN/Scr over several years
This type of AKI presents with concentrated urine
Prerenal or Functional
Causes of Prerenal AKI
4. Volume depletion
6. NSAID, ACEI/ARB, cyclosporine
Functional AKI MOA?
Decrease in glomerular hydrostatic pressure
What is the expected increase in Scr after ACEI/ARB initiation?
When does a rise in Scr occur after ACEI/ARB initiation?
2-5 days, stabilizing after 2-3 weeks
Functional AKI causes
mostly medication related: NSAIDs, ACEI/ARBs, Cyclosporine, Tacrolimus
How do cyclosporine and tacrolimus cause Functional AKI?
either through a decrease in vasodilators or increase in vasocontrictors
what AKI typically shows fever and rash?
Acute allergic interstitial nephritis
AKI showing dilute urine and casts
Most common type of intrinsic AKI
Intrinsic AKI causes
1. long-standing hypoperfusion
2. Nephrotoxins (Amg, Contrast, Carboplatin, Cisplatin, Ampho B)
AKI presentation of aminoglycosides
1. 6-10 days
2. usually nonoliguric
3. electrolyte wasting
Contrast-induced AKI presentation
1. initial osmotic diuresis followed by proteinuria
2. usually w/in 24 hours w/ Scr peaking after 2-5 days
Drug prevention of contrast-induced AKI?
2. Ascorbic acid
Prevention of contrast-induced AKI?
1. 6-12 hours before procedure
2. maintain UOP >150 mL/hr
3. NS or sodium bicarb
Avoid large doses (>140 mL)
avoid hyperosmolar agents
Amphotericin B-induced AKI presentation
1. usually starts after 2-3 g
2. electrolyte wasting
3. inc in Scr
Prevention of Amphotericin B-induced AKI?
1. limit total dose
2. NS 1 L before each dose
3. use liposomal product if possible
Tx of ATN?
nothing specific recommended. Remove causative agents
Causes of acute allergic interstitial nephritis?
B-lactams and NSAIDs
tx of acute allergic interstitial nephritis
d/c causative agent
initiate steroids in necessary for systemic symptoms
Presentation of B-lactam-inducted AKI?
1. w/in 1-2 weeks of tx
2. fever, rash, pyuria, proteinuria, eosinophilia, eosinophiluria
Urinalysis of Post renal AKI?
Urine Na - >40 mEq/L
Ur osmolality - low
RBC - positive
MOA of Postrenal AKI
obstruction of urine flow after glomerular filtration
General causes of Postrenal AKI
1. Renal tubular obstruction (precipitation of tissue/drug products)
2. Bladder outlet obstruction
Medications that can cause postrenal AKI
Dx of medication-induced postrenal AKI
needle-like crystals in leukocytes on urinalysis
Presentation of renal tubular obstruction?
Rapid decline w/ oliguric or anuric AKI
Tissue precipitation products that can cause post renal-AKI
uric acid (esp after tumor lysis)
myoglobin (from rhabdo)
Rowland-Tozer estimate equation
Q=1 - [(Fe(1 - KF)]
Q - dose adjustment factor
Fe - fraction of drug excreted unchanged
KF - ratio of pt's CrCl to normal (120 mL/min)
1. for hypoalbuminemia
Conc measured/[(0.2 x measured albumin) + 0.1]
2. for renal failure
conc measured/[(0.1 x measured albumin) + 0.1]
Proximal Convoluted Tubule: Reabsorbs what?
65% Na (as Cl- and HCO3)
Proximal Convoluted Tubule: Secretes what?
Acetazolamide: class and location of action
carbonic anhydrase inhibitor. Works in the PCT
Loop Diuretics: location of action
thick ascending limb of Henle
Thiazides: location of action
distal convoluted tubule
Spironolactone: location of action
cortical collecting tubule
Vasopressin antagonist: location of action
medullary collecting duct
Ca++ reabsorbed in ________ under PTH control
water reabsorption under vasopressin control here
medullary collecting duct
Thick ascending limb: diluting or concentrating segment?