Renal Diagnostics 🥼 Flashcards
Where does serum creatinine come from?
Breakdown of creatinine in skeletal muscle and from dietary meat intake.
What happens to creatinine in the kidney?
Released into circulation at a constant rate, and is freely filtered and excreted
What is a normal creatinine?
0.5-1.2
Where does BUN come from?
A product of protein catabolism
What kinds of things other than kidney problems can increase BUN?
Dehydration
GI bleed
Medications (Steroids and Tetracyclines)
What ratio can be used as a marker for volume status?
BUN/Creatinine ratio
BUN elevated= dehydrated
What is this:
Rough measure of the number of functioning nephrons
GFR
Can we directly measure GFR?
No
What measurement do we use to estimate GFR?
Creatinine clearance
What lab value will the pharmacist ask you for if you need help renally dosing a med?
Creatinine clearance
If someone is on dialysis, what stage of CKD are they at?
5 (no matter what their GFR is)
What stage CKD:
GFR: 90+
Stage 1
“Kidney damage with normal or increased GFR
What stage CKD:
GFR 60-89
Stage 2.
“Kidney damage with normal or decreased GFR)
What stage CKD:
GFR: 30-59
Stage 3
“Moderately decreased GFR”
WHat stage CKD:
GFR 15-29
Stage 4
“Severely decreased GFR”
What stage CKD:
GFR <15
Stage 5
“Kidney failure”
If you suspect lupus (SLE) what lab test do you need to order?
Antinuclear antibodies (ANA)****
double stranded DNA antibody
If you suspect GPA, what lab tests do you need to order?
C-ANCA
P-ANCA
**
What lab test do you need to order if you suspect Goodpasture syndrome
/
Anti-glomerular basement membrane antibodies (anti-GBM) ****
Why do we measure Prostate-Speciifc Antigen?
Screening method for early detection of prostate cancer
Monitor cancer after treatment
What can cause increased PSA levels
Prostate cancer
BPH
Prostatitis
Following prostate manipulation (ultrasound, biopsy, DRE)
not always elevated due to cancer
One of the first signs of kidney disease may be:
Protein in urine
Is protein in the urine ever normal?
No. Do not ignore it
RBC casts in the urine may indicate:
Glomerulonephritis
Vasculitis
WBC casts in the urine may indicate:
Tubulointerstitial disease
Acute pyelonephritis
Glomerular disorders
Epithelial cell casts in the urine may indicate:
Acute tubular necrosis*
Glomerulonephritis
Hyaline casts in the urine may indicate:
Dehydration
What kind of crystal may appear in the urine?
Uric acid
Calcium phosphate
Calcium oxalate
Cystine
Magnesioum ammonium phosphate (struvite)
What does a urine culture and sensitivity tell you
Identifies causative organism of UTI
Shows Antibiotic sensitivity and resistance
What is this:
“The earliest clinically detectable stage of diabetic nephropathy (or other early kidney damage)”
Microalbumin
Urine eosinophils are most commonly seen in _____________
Acute interstitial nephritis
What is Urine Protein Immunoelectrophoresis (UPEP) used to screen for?
Bence-Jones Proteins (multiple myeloma)
Why would you do a 24 hour urine collection?
Provides a better quantitative measurement for proteinuria or GFR
What is the name of the specific X-ray view used to evaluate urological stuff
KUB film
Kidneys ureters, and bladder
What can you see on a KUB film?
Calcification in the urinary tract (with some exceptions)
Prostatic calculi
Bladder distention
What kinds of stones will NOT be seen on a KUB film?
Small stones
Radiolucent stones (URIC ACID)***
Stones overlying bony structures
****
What is a “stag horn” pattern on a KUB film?
Stones that involve the renal pelvis and extending into 2 or more calyces
What is the test of choice to exclude*** urinary tract obstruction?
Renal ultrasound
Non invasive, no contrast required
What kind of imaging is best used to evaluate renal vascular flow
Renal Doppler Utrasonography
Which is more sensitive to detect a renal mass: US or CT
CT
If you do an ultrasound of a kidney and see a “hypodense mass with internal echoes” what are you looking at
Acute pyelonephritis
What is the test of choice to diagnose nephrolithiasis
Non-contrast CT
Can detect uric acid stones not seen on KUB
What imaging do you use to distinguish between a benign and malignant cyst
CT scan
How long after using contrast in a CT do you have to hold Metformin
48 hours afterwards
If you see a “stranding” pattern on CT what do you suspect
Pyelonephritis
What is the gold standard for diagnosis of renal vein thrombosis
MRI
No gadolinium is GFR is less than ______
30
What are the contraindications for MRI/MRA
Chronic renal failure with GFR<30
Acute renal failure of any severity
What is an intravenous Pyelogram?
You inject contrast and take x rays to look at how the kidneys excrete it
Why dont we use intravenous pyelograms very much
Requires contrast dye
Much more informative tests exist (CT)
(Why give them contrast and then just do Ann x ray)
What might we use renal angiography for?
Preoperative mapping of renal vasculature (looking for blockages etc)
If you do a renal angiography and see the classic “string of pearls” appearance of the renal artery, what disease is it
Fibromuscular dysplasia
How do you do a cystourethrogram?
Bladder is filled with contrast
X rays are taken while the patient is voiding
(Contrast is ONLY in bladder=less damage to kidneys)
What can you use cystourethrogram to diagnose
Vesicoureteral reflux
What is a cystoscopy
A flexible or rigid camera tube is inserted through urethra and into the bladder to loook around
What do you need to tell your patient after you do a cystoscopy?
Post procedure hematuria is expected and should clear within 3** voids
What are the potential compliacation of cystoscopy
Sepsis
Hemorrhage
Perforation of the bladder**
Dysuria
What test will be done on any male with testicular pain
Testicular ultrasound with DOPPLER
How do you do a prostate ultrasound and biopsy?
Transrectally (TRUS)
Helpful in detection of prostate cancer in patients with high PSA
