Renal - FA Embryo,Anat/Phys p566 -582 Flashcards
pronephros develops in which week?
week 4
mesonephros contributes to which adult structure?
male genital system
metanephros appears in which week?
week 5
uteric bud gives which adult structures?
ureter, pelvises, calyces, collecting ducts
interaction between uteric bud and metanephric mesenchyme leads to what?
differentiation and formation of glomerulus through DCT
most common site of obstruction in kidney
uteteropelvic junction - bc last to canalize - seen as hydronephrosis
A neonate has just been born and looks abnormal at birth. He has low set ears and flattened nose. His GFR is very low. What is the possible Dx, and symptoms associated with it
- P ulmonary Hypoplasia (MC cause of death)
- O ligohydramnios
- T wisted face
- T wisted skin
- E xtremity defects
- R enal Failure
What causes Potter sequence in utero?
Oligohydramnios due to inability of fetus to urinate or because of placental insufficiency
ARPKD
Obstructive uropathy
bilateral renal agenesis
A 1 year old boy comes in with severe abdominal pain, and has had a prolonged Hx of malabsorption. The physician diagnoses ischemia of the bowels. He is also irritated that the OB/GYN missed something on the fetal ultrasound. The CT scan shows a drastic abnormality leading to an obstruction in the abdomen. What is the Dx?
Horseshoes kidney leading to IMA impingement leading to ischemia of the bowels
Horseshoe kidney seen which which genetic issues?
turners, trisomies
Compare and contrast Multicystic dysplastic kidneys and Duplex collecting System?
MCKD and DCS both have abnormal interactions of the ureteric bud leading to congenital rnal pathologies.
MCKD: abnormal intrxn b/w ureteric bud and mesenchyme. Predominantly nonhereditary and usually unilateral; bilateral leads to Potter sequence.
DCS: abnormal movement of ureteric bud to metenephric blastemia creating bifid ureter –> causes increased risk of obstruction and UTIs
What leads to unilateral renal agenesis?
Ureteric bud fails to develop and induce differentiation of metanephric mesenchyme –> complete absence of kidney and ureter.
most common cause of bladder outlet obstruction in male infants? sx?
posterior urethral valves; hydronephrosis and dilated/thick walled bladder on US
Left renal vein rec which two addtl v?
L suprarenal and L gonadal v
Which area of kidney is more susceptible to hypoxia, and ischemic damage?
renal medulla, it rec much less blood flow.
`Which kidney is preferred in living donor transplantation?
Left kidney, bc L renal v is longer.
A 30 year old labor induced female is going through a C section for her twins. After successfully giving birth, excessive bleeding is observed and the OB/GYN does a hysterectomy. What is a key finding she has to worry about when doing the procedure in order to avoid complications?
Water under the bridge - ureters pass under uterine artery/vas deferens. Ligation of the uterine artery (cardinal ligament) and not confuse it with the ureter.
What prevents urine reflux?
Muscle fibers within the intramural part of the ureter prevent urine reflux.
3 common points of ureteral obstruction?
ureteropelvic junction, pelvic inlet, ureterovesical junction
Blood supply to ureters?
Blood supply to ureter:
Proximal—renal arteries
Middle—gonadal artery, aorta, common and internal iliac arteries
Distal—internal iliac and superior vesical arteries
Why is albumin not filtered thru BM ?
it’s 3.6 nm, so could technically go through but does not bc of (-) ions on endoth/GBM cells
Kidney anatomy and pathologies that affect this area
- Small renal a
- Glomeruli
- renal papilla
- calices and ureters
- Bladder
- Small renal a - HTN/DB nephropathy
- Glomeruli - acute interstitial nephritis
- Renal papilla - Sickle cell, T2DB, analgesic nephropathy, sever acute pyelonephritis
- Calices ureters - acute renal colic (nephrolithiasis) 5. Bladder - inflammatory process/tumor
What % of the body is total body water, ICF, and ECF.
60% total body water
40% ICF, mainly composed of K+, Mg2+, organic phosphates (eg, ATP)
20% ECF, mainly composed of Na+, Cl–, HCO3–, albumin
How do we measure plasma volume level? ECF?
radiolabeling albumin for plasma, ECF by inulin or mannitol
Serum Osmo level?
Serum osmolality = 285–295 mOsm/kg H2O
Components of Glomerular filtration barrier?
Fenestrated capillary endothelium
Basement membrane with type IV collagen chains and heparan sulfate
Visceral epithelial layer consisting of podocyte foot processes
if podocytes lack nephrin protein - leads to what Dx?
Congenital nephrotic syndrome
Best way to estimate GFR?
Creatinine clearance
Renal Clearence
Cx = (UxV)/Px = volume of plasma from which the substance is completely cleared per unit time
Cx = clearance of X (mL/min). Ux = urine concentration of X (eg, mg/mL). Px = plasma concentration of X (eg, mg/mL). V = urine flow rate (mL/min).
Fx for GFR? Normal GFR = ?
GFR = Uinulin × V/Pinulin = Cinulin
GFR = Kf [(PGC – PBS) – (πGC – πBS)]
GC = glomerular capillary; BS = Bowman space; πBS normally equals zero; Kf = filtration coefficient
Normal GFR = 100mL/min
Best way to estimated RPF?
PAH clearence
Fx for Renal blood flow - what % of CO?
Renal Blood flow = PRF / (1 - Hct)
20-25% of CO
Normal FF?
20%
How do PGs change GFR, RPF, and FF? What drug would inhibit it?
Prostaglandins preferentially dilate aff arteriole - Inc RPF, Inf GFR, so no change FF. This is inhibited by NSAIDS.
What preferentially constricts efferent arteriole? How does that change GFR, RPF, FF? What drug blocks it?
Angiotensin II,
- dec RBF
- inc GFR
- Inc FF.
(-) by ACEI
Fill in the chart
How much of something (X) was filtered? (Give Fx for filtration rate)
GFR (Creatinine clearence) x Plasma conc of (X)
How much of (X) excreted?
Excretion rate = Vol x Urine conc of (X)
Reabsorption?
Filtered - excreted
Secretion?
Excreted - filtered
Normal plasma level of glucose, where and how much reabsorbed?
Glucose at a normal plasma level (range 60–120 mg/dL) is completely reabsorbed in proximal convoluted tubule (PCT) by Na+/glucose cotransport.
At what glucose level will glucose begin to appear in urine?
In adults, at plasma glucose of ∼ 200 mg/dL, glucosuria begins (threshold). At rate of ∼ 375 mg/min, all transporters are fully saturated (Tm).
How does pregnancy affect GFR and glucose resorption in the kidney?
Normal pregnancy is associated with INC GFR. With INC filtration of all substances, including glucose, the glucose threshold occurs at lower plasma glucose concentrations –> glucosuria at normal plasma glucose levels.
What drugs can lead to glucosuria at plasma concentrations < 200 mg/dL
Sodium-glucose cotransporter 2 (SGLT2) inhibitors (eg, -flozin drugs) result in glucosuria at plasma concentrations < 200 mg/dL.
What is splay?
Splay is the region of substance clearance between threshold and Tm; due to the heterogeneity of nephrons.
Reabsorbs all glucose and amino acids and most HCO3–, Na+, Cl–, PO43–, K+, H2O, and uric acid.
early PCT
