Kidney Flashcards
What are the 2 most effective things you can do to slow the progression of CKD?
control BP and proteinuria
Is patient survival greater w/ a kidney transplant or dialysis?
transplant
What is the goal BP for a patient w/ CKD? Why is is lower than target BPs for other chronic dzs?
130/80
-because CKD is a RF for CVD
What are the 5 stages of CKD along w/ their corresponding GFRs? How long must kidney damage be present in order to qualify for a CKD dx?
- kidney damage s/ normal or ↑GFR (≥ 90)
- kidney damage w/ mildly ↓ GFR (60-89)
- moderately ↓GFR (30-59)
- severely ↓GFR (15-29)
- kidney failure (
What lab values are seen in patients w/ bone and mineral disorders (renal osteodystrophy) assoc. w/ CKD
- ↓ 1,25(OH)2 D3
- ↓ Ca2+
- ↑ P
- ↑ PTH
What are 3 of the major complications assoc. w/ CKD?
- mineral and bone disorders
- anemia
- metabolic acidosis
How and who do you screen for CKD?
screen for proteinuria in high risk populations (DM & HTN)
If urine dipstick is (-) for proteinuria in a high risk patient (DM, HTN), what should you look for next?
microalbuminuria
What are the 2 dietary restrictions that change for a patient when they have CKD vs. ESRD?
- protein intake (↓CKD | ↑ESRD)
- water intake (↑CKD | ↓ESRD)
hypo/hyper- natremia represent disorders of _____ homeostasis
water
Which ion is Plasma Osmolality mainly dependent on?
Na+
List 3 physiological stimuli for ADH release:
- ↑ Plasma osmolality (↑ serum [Na+])
- ↓ EABV (hypotension, hypovolemia)
- Endogenous stimuli (nausea pain)
List 4 etiologies of inappropriate stimuli for ADH release (SIADH):
- Drugs (SSRIs)
- Pulmonary dzs (like anything)
- CNS dz (tumor)
- malignancies
Would you expect urine osmolality to be high or low in SIADH? What about urine Na?
urine Na = urine osm (essentially)
both will be high → goal of ADH is to reabsorb water and [c] the urine
What lab values are consistent w/ true hypovolemic state?
Urine Na+
What is the first step in your ddx algorithm when checking for hyponatremia?
measure plasma osmolality
What is the first step in your ddx algorithm when checking for hypernatremia?
Check urine osmolality
What is the difference b/w central and nephrogenic diabetus insipidous?
central: complete lack of ADH
nephro: kidney not responding to ADH
What are the 2 necessary physiologic responses to defend against the development of hypernatremia?
- ADH secretion & response
- thirst
Which urine indices indicate low EABV? Which disorders of sodium balance will you find this in?
- ↓ Urine Na+
- ↓ FeNa and FeUrea
- total body sodium deficit →hypovolemic
- total body sodium excess →2° Na+ retention (d/t low EABV)
Common causes of total body Na+ defecit (3)
- GI losses
- diuretics
- aldo deficiency
Sole cause of 1° Na+ retention in hypervolemic state
renal failure
Common causes of 2° Na+ retention in hypervolemic state (3)
- CHF
- liver cirrhosis
- nephrotic syndrome
Low EABV leads to neurohumoral activation of __(3)___ and Na+ retention
- RAAS
- SNS
- ADH
proteinuria in nephrotic syndrome is defined as:
> 3.5 g
RBC casts in the urine (dysmorphic RBCs) indicates
nephritic syndrome
fatty casts/ lipid droplets in the urine indicates
nephrotic syndrome
broad waxy casts in the urine indicate
chronic GN
hematuria + mild proteinuria (
nephritic syndrome
Hallmark of acute renal failure
retention of nitrogenous waste products = azotemia (↑BUN and serum creatinine)
Define azotemia:
the accumulation of nitrogenous wastes in the blood (BUN and creatinine)
Define uremia:
ssx renal failure + azotemia
What is the first rule of AKI dx?
rule out obstruction!
Dx eval of post-renal AKI
measure post-void residual volume in the bladder via bladder cath
((+) = > 100 mL)
Key feature of this type of AKI is the ABSENCE of histological changes in the kidney
pre-renal AKI
Normal renal response to ↓ perfusion (RBF)
maintained afferent arteriole + vasoconstriction of efferent arteriole
Which nephritic syndrome is also accompanied by azotemia (type of intra-renal AKI)
acute nephritic syndrome (AIN)
MC GN
IgA nephropathy
MC nephrotic syndrome in young adults/ kids
minimal change dz
MC nephrotic syndrome in black people
Focal segmental glomerulosclerosis
Which urine indices help you differentiate pre-renal AKI vs AKI d/t ATN?
- FENa (or FEurea if on diuretic)
- Uosm
Urine osmolality value range for pre-renal AKI
> 500
Urine osmolality value range for intrinsic AKI
Uosm
FeNa (FeUrea) value range for pre-renal AKI
FeNa (FeUrea) value range for intrinsic AKI
> 2-3% (>55%)
WBC casts in urine w/o evidence of infx
AIN
Classic triad of:
-fever, rash, eosinophilia (AKI)
AIN
urgent Tx of hyperkalemia (esp. w/ EKG changes):
IV calcium gluconate
How do insulin and sympathetic hormones affect internal K+ balance?
push K+ inside the cell –> lower serum K+
How do acidosis and hyperglycemia affect internal balance of K+?
pull K+ outside the cell –> increase serum K+
