B5-042 CBCL: Kidney Failure Flashcards
developed in less than 3 months
acute
greater than 3 is chronic
prerenal vascular problems cause low blood flow/perfusion which leads to changes in
glomerular filtrating pressure
when the hydrostatic pressure in the glomerulus is lower, what happens to the net ultrafiltration pressure and GFR?
both lower
what type of kidney failure does renal artery stenosis cause?
prerenal
causes of intra-renal tubular injury
ischemia, toxins (ATN)
inflammatory (pyelonephritis)
pyelonephritis causes the inability to concentrate urine, leading to […]uria
polyuria
acute tubular necrosis (ATN) causes an intial phase of […]uria
oligouria
heavy proteinuria (>3.5 g/day)
nephrotic or nephritic
nephrotic
hypoalbuminemia with pitting edema
nephrotic or nephritic
nephrotic
hyperlipidemia and hypercholesterolemia
nephrotic or nephritic
nephrotic
hematuria
nephrotic or nephritic
nephritic
oligouria and azotemia
nephrotic or nephritic
nephritic
RBC casts and dismorphic RBCs in urine
nephrotic or nephritic
nephritic
proteinuria below 3.5 g/day
nephritic
what is the first thing that happens when the kidneys don’t function properly?
volume overload
what is the most important reason volume overload occurs?
sodium retention
how does kidney insufficiency cause acidosis?
low acid excretion –> accumulates
what type of anemia accompanies kidney insufficiency?
normocytic, normochromic anemia
kidneys can’t make EPO
treatment for anemia caused by renal insufficiency
EPO
iron supplement
B12 and folate supplements
signs of bone disease in kidney insufficiency
- bone pain
- increased risk of fracture
- osteomalacia
- rickets (kids)
how does renal insufficiency cause bone disease?
3
- kidneys activate vitamin D, which is necessary to increase/maintain calcium levels in plasma
- reduced GFR –> less phosphate excretion —> stimulates PTH secretion
- metabolic acidosis
treatment for bone disease in renal insufficiency
calcitriol
calcium supplement
how do you measure function of the tubules?
using fractional excretion of sodium
the clearance of […] is used to measure GFR
creatinine
as kidney function decreases, plasma creatinine
increases
normal value of FE Na
1-3%
indicator of both glomerular and tubular function
BUN/creatinine ratio
filtered and reabsorbed in the tubules and provides an estimate of GFR and tubular function
urea
BUN
normal BUN/Cr
15-20
useful to differentiate the origin of kidney failure (prerenal, intrarenal, postrenal)
BUN/Cr
glomerular function impaired
tubular function intially maintained
prerenal, intrarenal, or postrenal
prerenal
glomerular function intially maintained
tubular function impaired
prerenal, intrarenal, or postrenal
intrarenal
glomerular pressure and function impaired
tubular function impaired at late stages
prerenal, intrarenal, or postrenal
postrenal
- decreased GFR
- Azotemia, oliguria
- increased BUN
- Normal FE Na
- Normal osmolarity
prerenal, intrarenal, or postrenal
prerenal
- azotemia
- oliguria with brown casts
- decreased BUN/Cr
- elevated FE Na
- low osmolarity
prerenal, intrarenal, or postrenal
intrarenal
- azotemia, oliguria
- decreased GFR
- decreased BUN/Cr or normal
- elevated FE Na
- low osmolarity
prerenal, intrarenal, or postrenal
postrenal
treatments to control hypertension
- sodium restriction
- diuretics
- ACE/ARBS
- beta blockers
- calcium channel blockers
treatment of patients with renal insufficiency should aim to control
4
- hypertension
- electrolytes
- pH
- anemia
involves more than 50% of glomerulus
diffuse
less than 50% = focal
portions of the glomerulus affected
segmental
all = global
thickening of capillary wall
membranous
combination of membranous and proliferative = membranoproliferative
hypercellularity in glomerulus, mesangial expansion
proliferative
combination of membranous and proliferative = membranoproliferative
sclerosis with capillary collapse
glomerulosclerosis
nephrotic triad
- proteinuria
- hypoalbuminuria
- hyperlipidemia/cholesterolemia
- most common in children
- usually idiopathic
- podocyte effacement
- excellent response to corticoids
minimal change glomerulonephritis
- most common in hispanic or AA
- idiopathic or associated with sickle cell and HIV
- partial sclerosis of some glomeruli
- podocyte effacement
focal segmental glomerulosclerosis
- most common in white adults
- idiopathic or associated with NSAID, malignancy, chronic antigenic stimulation
- thickening of GBM
- granular IgG and C3
- sub-epithelial deposits
membranous glomerulonephritis
- most common cause of ERSD in US
- sclerosis of mesangium, KW nodules
- hyaline artherosclerosis of arterioles
diabetic nephropathy
- amyloid in mesangium/expanded mesangium
- green birefringence under polarized light with Congo Red
amyloidosis
characteristics of glomerulonephritis
5
- glomerular inflammation/hematuria
- oliguria
- azotemia
- RBC casts/dysmorphic RBCs in urine
- proteinuria below 3.5
- after Group A hemolytic strep infection
- reduced C3-C4 in first 6-8 weeks
- hypercellular inflammed glomeruli
- immunocomplex deposition (sub-epithelial humps)
post-streptococcal glomerulonephritis
- progresses rapidly to renal failure
- ANCA
- presents with rapidly progressive glomerulonephritis
- cresents of fibrin in Bowman’s space
ANCA-associated glomerulonephritis
ANCA-associated vasculitis
- inherited alteration of type IV collagen
- thinning and splitting of GBM
Alport syndrome
- anti-GBM antibodies
- IgG deposition along glomerular capillary loops
- fibrin in crescents
- linear or diffuse IgG staining of GBM
- responds to corticosteroids
Goodpasture syndrome
diseases that cause glomerulonephritis and can lead to both nephrotic/nephritic syndromes
3
- membrane proliferative glomerulonephritis
- IgA nephropathy (Berger)
- Lupus nephropathy
- Ig+ with chronic antigenemia or Ig- with alternative complement antibodies
- double contours and lobular hypercellularity
- sub-endothelial deposits
membrane proliferative glomerulonephritis
- common in young white males and asians
- IgA granular deposit in mesangium and hypercellularity
IgA nephropathy (Berger)
- “full house” (IgG, IgA, IgM, C3, C1q)
- deposits everywhere, GB may show dense depositis
lupus nephropathy
- episodic hematuria after infection
- Henoch-Shein purpura
- proteinuria –> nephritic syndrome
- rarely progress to nephrotic syndrome
IgA nephropathy (Berger)
- focal or segmental glomerular mesangial expansion
- deposits of IgA in glomerular membrane
- healing lesions may lead to sclerosis
IgA nephropathy
genetic or acquired abnormality of immune regulation with abnormal increase in the polymeric form of secretory IgA in blood
IgA nephropathy
in IgA nephropathy, IgA is abnormally […]
glycosylated
IgA trapped in glomerular mesangium causing it to proliferate
IgA nephropathy
diagnosis of IgA nephropathy
- urine test for blood or protein
- kidney biopsy for IgA
treatment of IgA nephropathy
- HTN medications
- inmunosuppressants (steroids)
- omega-3 fatty acids
- fatigue, headaches, malaise
- nausea, vomiting, lack of appetite
- itchy skin, leg swelling
diabetic nephropathy
microalbuminuria at first, then progresses to heavy proteinuria
diabetic nephropathy
- GBM thickening
- mesangial widening with KW nodules
- intracapillary glomerulosclerosis
- hyalinosis
- tubulointerstitium
diabetic nephropathy
caused by high glucose levels and protein glycosylation
diabetic nephropathy
diagnosis of diabetic nephropathy
- urine test for microalbuminuria or proteinuria
- US of kidneys
treatment of diabetic nephropathy
- HTN medications
- control ESRD
what amount of urine is associated with oliguria?
< 400 mL/day
common skin symptom of patients in ESRD
pruritis
related to high BUN levels
what indicates recovery in nephrotic syndrome?
disappearance of protein from urine
characterized by hematuria, proteinuria, edema, oliguria, azotemia
nephritic syndrome
sudden reduction in renal function after infectious glomerulonephritis will present with
3
- hypertension
- oliguria
- fatigue
- back pain
- nausea
- vomiting
associated with
renal calculi
- dysuria
- frequent urinating
symptoms of
UTI
diabetic nephropathy progresses into
nephrotic syndrome
what filtration pressure does hydronephrosis increase?
hydrostatic pressure in Bowman’s capsule
which filtration pressure would multiple myeloma impact?
increase oncotic pressure in glomerular capillaries
hypotensive hospitalized patients are the most common antecedent to
acute tubular necrosis
earliest event in glomerulonephritis
loss of negative charge of GBM
extreme pruritis and crystallized white deposits are associated with
increased urea
what type of diet is best for ESRD?
low protein
low sodium
low potassium
low phosphate
chronic kidney diease, DM, and vomiting all can lead to
primary metabolic acidosis
as kidney disease progresses, the distal nephron loses its ability to secrete K+ leading to
hyperkalemia
renal insufficiency is accompanied by […] retention
sodium
most common manifestation of acute renal failure secondary to NSAIDs
hyperkalemia
in ESRD, lack of activation of vitamin D causes
spontaneous fractures
broad and waxy casts
chronic renal failure
muddy brown granular casts
acute tubular necrosis
red blood cell casts
nephritis
white blood cell casts
2
- interstitial nephritis
- pyelonephritis
renal insufficiency is accompanied by
4
- anemia
- low bone density
- hypervolemia
- hyperkalemia
three most common causes of CKD
- DM
- HTN
- glomerulonephritis
urinary casts indicate
tubular damage
does renal insufficiency cause hypo or hyper kalemia?
hyperkalemia
does renal insufficiency cause hypo or hyper natremia?
hypernatremia
does renal insufficiency cause hypo or hyper calcemia?
hypocalcemia
does renal insufficiency cause hypo or hyper phosphatemia?
hyperphosphatemia
renal damage accompanying DM leads to excessive release of
2
renin and aldosterone
filtration in the glomerulus is […] in renal insufficiency
decreased or increased
decreased
plasma sodium is […] in renal insufficiency
increased or decreased
increased
fibromuscular dysplasa and renal artery stenosis cause […] kidney insufficiency
pre renal
kidney stones cause […] kidney insufficiency
post renal
commonly presents after an infection of the respiratory tract
Berger (IgA nephropathy)
first sign of Berger
hematuria
brown cell casts and urine sediment
acute tubular necrosis
consequences of renal failure
Metabolic Acidosis
Dyslipidemia
High potassium
Uremia
Na+/H2O retention
Growth retardation
Erythropoietin deficiency
Renal osteodystrophy
MAD HUNGER