nephro Flashcards
basic filtering unit of kidney
nephron
area where you can hear a bruit
L1
3 layers fluid must go through in bowman’s capsule
Fenestrated endothelial cell Glomerular basement membrane (GBM) Epithelial cell (with podocytes and little feet)
Macula Densa in the ______ and JG cells in the ____ arteriole make up the JGA.
distal tubule, afferent
what stucutre helps regulate the GFR?
Juxtaglomerular apparatus (tubuloglomerular feedback)
what structure synthesizes pro renin?
JGA cells
when is pro renin secreted?
when decreased circulating volume or hypoperfusion
T or F: the kidney Regulats volume and composition of body fluids to maintain a constant extracellular environment for adequate functioning of cells.
T
what waste and metabolic breakdown does kidney filter?
Ammonia, urea and creatinine
Uric Acid
Drugs and toxins.
T or F: impaired kidney function will not affect insulin
F: impaired kidney function can extend half life of insulin!
what hormones does the kidney degrade?
Metabolic degradation of peptide hormones such as pituitary hormones, glucagon, insulin
Increased EPO in states of hypoxemia:
anemia, chronic lung disease, high altitudes.
when do you see decreased EPO?
Chronic Kidney Disease due to reduced EPO production by the kidney.
kideny enzyme that forms 25 oH D from vitamin D product from liver
1 alpha hydroxylase
most potent form of vitamin D that helps us absorb calcium
25 OH D
what converts angiotensinogen (made in liver) to angiotensin?
renin
what does angiotensin II do?
Systemic Vasoconstriction which raises systemic BP
Na and water reabsorption in PT helps to restore volume
Secretion of Aldosterone
vague sx in renal disease
fatigue, weight loss, anorexia.
specific sx in renal disease
hematuria, dark urine, foamy urine, peri-orbital and peripheral edema, HTN, rashes, joint pains/arthralgias, recent URI, incomplete bladder emptying
med questions in taking renal history
what meds (esp antibx) have they taken, drug abuse, hx of NSAID use
FH questions to ask in renal patients
renal dz/transplant/dialysis
PMH to ask in renal patients
hx of stones, UTIs
PE signs in renal disease patients
Signs of systemic illness: DM, HTN
Assess volume status: edema, JVP, BP.
Examine skin for rash, purpura.
Examine joints if hx of arthralgia
what can flank pain or tenderness mean?
Renal infection
Renal infarction
Glomerulonephritis
Rarely obstruction
what can severe/colicky pain mean in renal patients?
Renal or ureteric colic +/- radiation to iliac fossa, groin and genitalia
Acute obstruction of the renal pelvis and ureter by renal calculus or blood clot
sx of lower UTI
Dysuria
Frequency
Urgency
bladder outflow obsturction sx
Impaired urinary flow
Hesitancy
Dribbling
Incomplete emptying of bladder
sphincter or bladde real dysfcn a
Urinary retention
Incontinence
Enuresis
abnormal urine volume ddx
Acute renal failure or obstruction to urine flow
Anuria
Oliguria
Failure to concentrate urine (Diabetes Insipidus, CKD)
Polyuria, nocturia.
what does proteinuria suggest?
Suggest glomerular disease
Massive proteinuria causes edema
best time for UA
early AM, mid-stream clean catch specimen.
what do these colors in urine mean?
Dark yellow to green
Red to black
Purple to brown on standing to light
Dark yellow to green (Bilirubin)
Red to black (erythrocytes, hemoglobin, myoglobin)
Purple to brown on standing to light (porphyrins)
normal urine color
(yellow to amber)
normal urine ph
(Normal pH 4.6 to 6.0)
increased urine ph
Infection with urea-splitting organism (proteus)
Systemic alkalosis, renal tubular acidosis, carbonic anhydrase inhibitors
normal specific gravity
(Normal 1.003 to 1.030)
increased urine specific gravity ddx
Fasting and dehydration, glycosuria, proteinuria, radiographic contrast media.
decreased urine specific gravity ddx
Compulsive water drinking, diabetes insipidus
T or F: protein in urine is normal
F: persistent proteinuria indicates renal disease; if one time it is elevated, retake the test if no indication of a glomerular problem
Persistently positive dipstick proteinuria should be quantified how?
24 hour Urine collection or Spot albumin-to-creatinine ratio.
what do ketones in the urine mean? causes?
Ketones in urine indicate that metabolism is dependent upon fatty acids rather than glucose for energy
causes: Diabetic Ketoacidosis, starvation, fasting, alcoholic ketoacidosis.
Glycosuria in setting of normal plasma glucose:
Defect of Proximal tubule reabsoprtion such as Fanconi syndrome, myeloma, exposure to meds such as tenofovir, lamivudine, cisplatin, valproic acid and aminoglycoside
what can cause a false + blood on dipstick?
hemoglobin and myoglobin, even when no RBCs on micro
high BUN seen with…
dietary intake (high protein diet) high catabolic rate and tissue breakdown (hemorrhage, trauma, glucocorticoid therapy. Dehydration
nml or low bun seen with
Muscle wasting and liver disease.
causes of pre-renal 20:1 BUN/cr
decreased blood flow
causes of normal or post renal 10-20:1 BUN/cr
obstruction
causes of
Renal damage causes reduced reabsorption of BUN, therefore lowering the Bun: Cr ratio.
Eliminated exclusively by the kidneys and therefore can serve as an indicator of renal function
creatinine
creatinine vary according to…?
person’s size and muscle mass hence lower in women and elderly
what is a 24 hour creatinine clearance?
estimate Glomerular Filtration Rate (GFR) by comparing the level of creatinine in urine with the creatinine level in the blood
Requires serum sample and 24 hour urine collection: Ucr x Volume/ Pcr.
equation used to calculate GFR
cockcroft gault EQ
best initial test to visualize kidney
US
indications for renal ultrasound
renal masses
obstruction/hydronephrosis
fluid collections or other signs of inflammation/infection
MAY detect nephrolithiasis (but CT better)
hematuria,
Acute Kidney Injury
flank pain
safe during pregnancy
+ doppler for suspicion of renal artery stenosis
T or F: CT is better than MRI for characterizing abnormal tissues/masses especially when there is concern for malignancy
F
special test you can do if someone has frequent UTIs, hematuria, incontinence, painful urination, etc
cystoscopy or voiding cystourethrogram
can you biopsy a kidney/
no! leave that to urologists–you could create a tract for malignant cells to go
American urologic association of hematuria
> than 3 RBCs per High Power Field in 2-3 properly collected urine on two separate urinalysis over a 2 week period.
T or F: its normal for someone on warfarin to have a few RBCs in urine
F: they should not have hematuria
what is it called when RBCs may get trapped in a specific protein in the distal convoluted tubule and stick together and can be seen on microscopy
casts
causes of glomerular hematuria:
glomerulonephritis, vasculitis, Iga nephropathy, thin basment membrane nephropathy, hereditary nephritis (alport syndrome), chronic intersitial nephritis (inf
how do you distinguish extraglomerular hematuria from glomerular hematuria?
normal appearing RBCs in urine (b/c haven’t been crunched when going through glomerulus)
causes of extraglomerular hematuria
Infections Nephrolithiasis (kidney) Calculus (bladder, urethra) Malignancy Cystic disease (PKD) Vascular disorders AVM, renal vein/artery emboli/infarct, papillary necrosis (DM, Sickle Cell Disease, NSAIDs)
symptoms of extra glomerular hemauria
Dysuria, pyuria, fevers UTI, pyelonephritis, prostatitis, urethritis, malignancy Urethral discharge Urethritis, prostatitis Flank pain Pyelonephritis, stones, neoplasm, ischemia, GN Hesitancy, dribbling BPH
signs or sx of glomerular hematuria
Gross, painless hematuria :bladder cancer, post-infectious GN, Cancer
Fevers, rash, arthritis : GN associated with Vasculitis such as Systemic Lupus Erythematosus.