Renal Quiz 1b Flashcards
What does the presence of casts suggest?
That the hematuria/pyuria is of renal (as opposed to bladder) origin.
What can cause RBC casts?
a. glomerulonephritis
b. malignant HTN
c. renal ischemia
d. vasculitis
What can cause WBC casts?
a. tubulointerstitial inflammation
b. acute pyelonephritis
c. transplant rejection
What can cause “muddy brown” casts?
acute tubular necrosis
What can cause waxy/fatty casts?
nephrotic syndrome
What can cause hyaline casts?
non-specific, can be a normal finding
What causes the straight line in immunoflorescence?
IgG… common with Goodpastures.
What causes big clumps on immunoflorescence?
IgA. Common in Berger’s.
What are the 3 types of renal cell carcinomas?
a. Clear-cell carcinoma: defect in VHL (von Hippel-Lindau)
b. Papillary renal cell carcinoma: defect in MET
c. Chromophobe renal carcinoma: lost chromosome (!)
What is the classic triad of symptoms for renal cell carcinoma?
a. painless hematuria
b. palpable flank mass
c. flank pain
What is the most common demographic for renal cell carcinoma?
60-70 y/o male.
Where do transitional tumors usually occur? What is an indication?
Urinary tract outside of kidney, common in the bladder.
Risk factors (age of 50-70, smoking, etc.) + painless hematuria = suspicion
What is the Wilms tumor pneumonic?
W: Wilms tumor
A: Aniridia (no iris)
G: Genitourinary malformation
R: Retardation (mental-motor)
Who does Wilms Tumor (Nephroblastoma) usually hit? What is the genetic indication?
Children 2-5 y/o.
Loss of WT1, a tumor supressor gene on chromosome 11.
What type of junction are the slit barriers at the level of the foot processes of the podocytes?
modified tight junctions.
How do the podocytes communicate with endothelial cells?
VEGF
What is the charge of the charge barrier, and what is believed to hold the charge?
The glycocalyx is believed to have a negative charge.
What catches low MW proteins that get thru the glomerulus, and what happens to these proteins?
- Take up in PCT by megalin, cubilin and amnionless
- processed in lysosomes and AAs are scavenged and reabsorbed
What is the dominant site of resistance to flow in the kidney?
afferent arteriole
What is the principle signal for efferent arteriole resistance?
Angiotensin
How does high Na+ affect the afferent arteriole? How does it affect the efferent arteriole?
Reabsorption of Na+ goes thru the basolateral side of the cell using a Na/Cl ATPase transporter. The resulting ADP causes the mesangial cells to contract the afferent arterioles, and reduce flow.
High Na+ also decreases AngII which widens the efferent arteriole.
What hormone is released when volume is too high, and it decreases Na+ reabsorption?
Dopamine
What effect does AngII have on the PCT?
It increases Na+ reabsorption.
What causes release of ANF and what does it do?
Stretch of atria releases, and it decreases Na+ reabsorption.
What is the diluting limb? Why is it called that?
Thick ascending. It reabsorbs 2Cl-, Na+ and K+, but does not reabsorb H2O.
Does an increase in sympathetics make renin?
yes
What causes periorbital edema?
Post-strep
What are the two presentations of IgG in IF?
a. ribbon-like: Goodpastures
b. lumpy-bumpy: post-strep
What do calcium stones look like?
a. dumbbell
b. pretty earrings
What shape are ammonium magnesium phosphate stones?
coffin-lid
What shape are cystine crystals?
cystine = six sides (very uncommon)
What shape are uric crystals?
rhomboid or rosette
