Renal Syndromes Flashcards
acute kidney injury
occurs in hours to weeks
possible recovery of some or all of the lost renal function
implies impaired ability of the kidneys to perform their normal physiologic functions
classifications of intrinsic acute renal failure
glomerular (5%)
tubular (85%)
interstitial (10%)
baseline parameters defining acute kidney injury
a rise in creatinine of 0.3 mg/dL
a decrease in GFR of 30-50%
What is the specific gravity of normal urine?
1.002 - 1.030
Major categories of acute tubular necrosis
ischemic in origin (60%)
toxic in origin (40%)
What does pigmented cast suggest?
ATN
rhabdomyolysis
What does a white cell cast suggest?
allergic interstitial nephritis
pyelonephritis
What are the parameters that signify proteinuria?
normal < 150 mg/day
30-300 albumin/day is microalbuminuria (diabetic)
> 300 mg/day is overt nephropathy
> 3000 mg/day is nephrotic syndrome
non-nephrotic range proteinuria
~2mg or less with no evidence of any systemic disease and an otherwise normal urine sediment
allergic (acute) interstitial nephritis
a rash in the kidneys
acute kidney injury from medication exposure
can also be caused by multiple myeloma, SLE, and sarcoid
stopping the offending agent often is curative, with steroids given if needed
clinical presentation of AIN
classic triad of rash, fever, and eosinophilia
can occur 2-3 days of exposure to agent, or after months
urinanalysis shows invariable hematuria, steril pyuria, mild proteinuria and +/- eosinphils
treatment for acute interstitial nephritis
remove offending agent
maintain adequate intravascular volume
steroids are believed to be beneficial, but no prospective, randomized trials support them
What are the types of glomerular renal syndromes?
nephrotic and nephritic
What are examples of nephrotic glomerular renal syndromes?
minimal change disease
FSGS
membranous
What are examples of nephritic glomerular renal syndromes?
immune complex mediated
anti-GBM disease
Pauci-immune
indications for renal biopsy
acute kidney injury of unknown etiology
nephrotic syndrome of uncertain etiology
nephritis of uncertain etiology
kidney dysfunction in a renal transplant patient
nephrotic syndrome
1) > 3.5 gm of proteinuria
2) hypoalbuminemia
3) lipiduria
4) hyperlipidemia
5) edema
How is proteinuria used to rule out nephrotic syndrome?
mild proteinuria is under 2 grams, or 1-2+ by dipstick
for neprhotic range proteinuria, there will be greater than 3 grams of protein in the urine a day
clinical presentation of glomerulonephritis
fever, malaise
edema
dark, tea colored urin - oliguria
hypertension
increased creatinine, azotemia
blood, protein in the urine (1-2+)
immune complex glomerulonephritis
IgA nephropathy
post-infections
systemic lupus erythematosus
membranoproliferative GN
IgA nephropathy
most common acute GN, men>women, more prevalent in asians
relapsing and remitting, associated with mucosal irritation - synpharyngitic hematuria
hematuria, proteinuria, and red blood cell casts
increased creatinine
normal complement levels
treating IgA nephropathy
avoid mucosal infection
treat nephrotic syndrome if present
fish oil is used if risk factors for disease progression
can also use ace-inhibitor or angiotensin receptor blockers
if severe, add on steroids
post-infectious GN
any age, usually children, mostly males
clasically, 1-3 weeks after group A beta-hemolytic strep infection
presents with edema and hypertension RBC casts, acanthocytes, hypocomplementemia
diagnosis of Post-infectious glomerulonephritis (PIGN)
nephritic syndrome 10-14 days after documented infection
fever, malaise, edema
low serum C3
nephritic urine
rising ASO iters
prognosis is excellent in children
treatment of PIGN
treat/clear infection
lupus glomerulonephritis (SLE)
any age, usually 20-40
female to male ratio is 9:1
usually associated with other features of SLE, nephritic sediment
diagnose with biopsy
red blood cell casts, +ANA, +ds DNA, low complement levels
treat with steroids, IV cyclophosphamide
membranoproliferative GN
any age, usually 5-30
associated with HBV, HCV, HIV, EBV, chronic infections, CLL, B-cell lymphomas
nephritic or nephrotic, low C3 (40%), low C4 (20%)
edema, dyslipidemia, if nephrotic
increased creatinine, hematuria, proteinuria if nephritic
can present with features of both
treat underlying cause - steroids in children and interferon for adults (for Hep C)
anti-GBM disease
rare - found mostly in young adult men and older women
pulmonary-renal syndrome caused by autoantibodies that bind to type IV collagen found in the glomerular basement membrane and lung
presents with hemoptysis and renal failure, with a 3 month gap inbetween onset of pulmonary disease and renal disease
associated with hydrocarbon fumes, cocaine, cigarette smoke
treat with plasmapheresis, steroids, or cyclophosphamide
ex. Goodpasture’s Disease
What are the classifications of glomerulonephritis?
immune complex
anti-GBM
pauci-immune
pauci-immune GN
normal complement levels, no specific immunofluorescence pattern
caused by granulomatosis with polyangiitis, microscopic polyangiitis, or Churg-Straus
rapidly progressive glomerulonephritis
double serum creatinine or halving of creatinine clearance in 3 months or less
pathology often reveals crescentic GN - infiltration of Bowman’s space with mononuclear cells in a characteristic crescentic pattern
often accompanied with endocapillary proliferation, focal necrosis, and tubulointerstitial cellular inflammation
signs of nephrotic syndrome
> 3.0 gm protein/day
severe edema
hypoalbuminemia
hyperlipidemia
lipiduria
minimal change disease
90% of nephrotic syndrome in children - explosive edema
selective proteinuria and non-selective proteinuria, selective thought to be less damaging
effacement of foot processes
symptoms include swelling of feet, history of cancer, medication exposure, dyslipidemia, proteinuria, oval fat bodies (maltese crosses) in sediment
kidney biospy to diagnose
treat with steroids and manage nephrotic syndrome
complications of nephrotic syndrome
edema
thromboembolic complications
infection
hyperlipidemia
treatment of nephrotic syndrome
treat underlying cause, if identified
control blood pressure
in diabetes, control B.S.
use ACE-inhibtors
control lipids
stop smoking
sodium restriction
tubulointerstitial diseases
often associated with subnephrotic (< 1-2 grams) range proteinuria and perhaps some renal insufficiency
creatinine is stable or increasing slowly
no active systemic disease symptoms of concern
often the result of an old renal inury
does not require biopsy or specific treatment
What are some common conditions that cause transient small amounts of proteinuria?
exercise, fever, and infection
What are the ranges of albumin in the urine, and what do they suggest?
30 mg to 300 mg - microalbuminuria in a diabetic
>300 mg - overt nephropathy
> 3000 mg - nephrotic range proteinuria
acute nephritic syndrome
represents the clinical sequelae of acute glomerular inflammation
hematuria, red blood cell casts in the urine, dysmorphic red blood cells, proteinuria, along with varying degrees of renal insufficiency, hypertension, and some edema are the clinical features
kidney disease with low complement levels
PIGN
SLE
granulomatosis with polyangitis (GPA - formerly known as Wegener’s Granulomatosis)
often presents as a pulmonary renal syndrome, pulmonary involvement ranges from a chronic sinusitis to hemoptysis
usually affects older individuals
symptoms include fever, weight loss, nose ulcerations, lung findings, hematuria, proteinuria, and red blood cell casts
+ANCA (usually C-ANCA, PR3 pattern)
kidney biopsy for diagnosis
treatment of GPA
small vessel vasculitis
degree of immunosuppression depends on the degree of organ involvement and damage
treatment ranges from low dose steroids or cellcept (an oral immunosuppressant) to high dose steroids and cyclophosphamide
treatment of microscopic polyangiitis
degree of immunosuppression depends on the degree of organ involvement and damage
treatment ranges from low dose steroids or mycophenolate mofetil (cellcept - an oral immunosuppressant) to high dose steroids and cyclophosphamide
microscopic polyangitis
pulmonary renal syndrome, with pulmonary involvement in the lower lung
can present acutely or chornically
usuall affects older individuals
symptoms include fever, wieght loss, lung findings, hematuria, proteinuria, and red blood cell casts
+ ANCA (usually P-ANCA, MPO patter, but C-ANCA also frequent)
kidney biopsy for diagnosis
Churg-Strauss
common in patients with asthma and eosinophilia with blood and protein in their urine
wheezing on lung exam if asthma is not controlled
eosinophils
hematuria, proteinuria, and red blood cell casts
+ ANCA up to 60% of the time (usually p-ANCA)
kidney biopsy to diagnose
treatment of Churg-Strauss
usually steroids control most maniestations, but if serious organ damage occurs, treatment can include high dose steroids and cyclophosphamide (like WG)
focal segmental glomerulosclerosis
idiopathic but can also be secondary to other conditions
men > women
African-American > White
assicated with HIV, heroin, obesity, sleep apnea, reflux
swelling usually appears over a prolonged time
dyslipidemia, proteinuria
oval fat bodies “maltese crosses” in urine
kidney biopsy to diagnose
treatment of FSGS
treat underlying disease
nephrotic syndrome treatment
if idiopathic, try steroids, immunosuppresants, or chemotherapy
membranous nephropathy
any age, uncommon in children
associated with cancer, medications (NSAIDs, gold, penicillamine), viral infections (Hep B, C, and HIV), and lupus
edema, dyslipidemia, proteinuria, oval fat bodiies “maltese crosses” in sediment
kidney biopsy to diagnose
thickened GBM, subepithelial deposits on EM
prognosis worse in men
treatment of membranous nephropathy
treatment depends on the amount of proteinuria
can vary from watchful waiting to steroids to chemotherapy (chlorambucil, cyclophosphamide) to modulate the immune system
