MTB Flashcards
Methods to assess total amount of protein in a day
- Single protein to creatinine ratio
2. 24 hour urine collection
WU for proteinuria
- UA
2. Protein to Creatinine (P/Cr)
What determines cause of proteinuria
Kidney BX
Diabetic pt with microalbuminuria - next step in management
Start ACE
Is Bence jones protein detectable on dipstick?
No
Must do immunoelectrophoresis
What stain is important in allergic interstitial nephritis
Wright and Hansel
Detect eosinophils in urine
DDX for Hematuria
Stones in KUB Heme disorders Infxn Cancer - KUB Cyclophosphamide Trauma Glomerulonephritis
Dysmorphic RBCs indicates
Glomerulonephritis
When is cytoscopy the answer
Hematuria w/out infxn Prior trauma AND Renal US or CT inconclusive Bladder sonography shows mass for possible BX
What is cytoscopy the most accurate test for
Bladder
visualizes bladder and urethra = areas that do not show up well on X ray
Red cell cast?
Glomerulonephritis
White cell cast?
Pyelonephritis
Eosinophil cast?
Allergic Interstitial Nephritis
Hyaline cast?
Dehydration
Broad, waxy cast?
Chronic Renal DZ
Granular muddy brown cast?
Acute Tubular Necrosis
Fatty Casts?
Nephrotic syndrome
Prerenal azotemia causes
Decreased perfusion
- Hypovolemia
- HypoTN
- Renal Artery stenosis
- Hypoalbuminemia
- Cirrhosis
- NSAIDs = constrict afferent arteriole
- ACE I = efferent arteriole VD
NSAIDs effect on kidney
Constrict afferent arteriole = decrease GFR
PGs dilate afferent to increase GFR
ACE-I impact on GFR
Worsen GFR - but prevent progression of renal insufficiency - long term protect glomerulus
Postrenal Azotemia causes
Obstruction = blocks filtration at glomerulus
- Prostate Hypertrophy
- Stone in ureter
- Cervical Cancer
- Urethral stricture
- Neurogenic bladder = MCC in DM and MS
- Retroperitoneal fibrosis
MCC of death in cervical cancer
postrenal azotemia - renal insufficiency b/c both ureters blocked
What is the major force favoring filtration in kidney
Hydrostatic pressure in glomerular capillary
Drugs that cause retroperitoneal fibrosis kidney
Bleomycin
Busulfan
Methylsergide
Radiation
MCC of intrinsic renal dz
ATN - ischemia and toxins
Presentation of AIN
Fever
Rash
Eosinophils
Causes of Intrinsic renal dz
AIN Rhabdomyolysis Hemoglobinuria Contrast agents Crystals Proteins Post strep infxn
Presentation of AKI
Asymptomatic rise in BUN and Creatinine
Sx’s - N/V, malaise, weakkness, SOB
Severe - Confusion, arrhythmia from hyperkalemia, acidosis. Pericarditis
Presentation of Postrenal Azotemia
Enlargement of bladder
Massive diuresis after Foley placement
Diagnostic test for Acute Kidney Injury
BUN
Creatinine
BUN/Cr ratio > 20:1
Prerenal Azotemia
Postrenal Azotemia
BUN/Cr intrinsic renal dz
Around 10:1
Best imaging test for acute kidney injury
Renal sonogram
Postrenal Azotemia
BUN/Cr > 20:1
Distended bladder, urine release w foley
BL or UL hydronephrosis on sonogram
When do we do kidney BX
Rarely correct answer
Most accurate for Allergic interstitial nephritis or poststrep GN
What is UNa and FeNa in Prerenal azotemia
Low UNa = < 20
Low FeNa = <1%
What is urine Osmolality in ATN
Inappropriately LOW
Isosthenuria - same as blood, about 300 mOsm/L
Tubule cells damaged = urine cannot be concentrated
Dehydration does what to osmolality (urine concentration)
Normally increases
In ATN, what happens to sodium
Body inappropriately loses sodium and water into urine
UNa > 20
UOsm < 300
Healthy person w fluid overload
Osmolality?
LOW urine Osmolality
Dilute urine
Healthy person w dehydration
Osmolality?
HIGH urine osmolality
Concentrated Urine
Sickle cell trait pts management
Advise avoid dehydration
Do not need other TX
What is Uremia
Renal insufficiency to the degree that dialysis is needed
What does urine specific gravity correlate to
Urine osmolality
Causes of ATN
Ischemia
Toxins
Renal Insufficiency with rapid onset
Contrast
Renal insufficiency drugs
How long to be nephrotoxic
Vanco Gentamicin Amphotericin Cisplatin Acyclovir Cyclosporine 5 to 10 days
Most proven benefit at preventing contrast-induced nephrotoxicity
Saline Hydration
Pathophys of contrast on kidney
Contrast causes spasm of afferent arteriole causing renal tubule dysfunction. High reabsorption of Na and water, causing high specific gravity of urine = VERY low urine Na
Tumor Lysis Syndrome
Hyperuricemia
Hyperkalemia
Renal failure prevention in chemo pts
Prior to chemo to prevent tumor lysis syndrome:
Allopurinol
Hydration
Rasburicase
Management of Hyperkalemia in tumor lysis syndrome
- Normalize cellular electrical activity with Calcium
- Drive K+ Intracellulary
- Decrease total body K+ content
- insulin and glucose = rapidly act to drive K+ intracellular within 15-30 mins
