Renal Flashcards
When is the ureteric bud fully canalized?
10wk
What do the
pronephros
mesonephros
metanephros become?
Pronephros- degenerates
Mesonephros- male gential system (interim kidney for 1st trimester)
Metanephros- filtration portion of kidney
Where does the ureteric bud start?
collecting duct
What presents as limb deformities, facial anomalies, low-set ears, retrognathia
Potter sequence (oligohydramnios)
What vessel does a horeshoe kidney get trapped under?
IMA
What is the cause of multicystic dysplastic kidney?
abnormal interaction between ureteric bud and metanephric mesenchyme
What percentage of body weight is
- total body water
- ICF
- ECF?
60% total body water
40% ICF
20% ECF
What are is used to measure plasma volume? ECF?
plasma volume- radiolabeled albumin
ECF- inulin
How is clearance calculated?
Cx=UxV/Px
What is a normal GFR?
100ml/min
What is used to calculate GFR? RPF?
GFR- inulin, creatinine clearance
RPF- PAH
What is FF? What is a normal value?
FF=GFR/RPF
normal= 20%
What is the effect of Ang II on RPF/GFR/FF? Why is this?
Ang II preferentially restricts efferent arteriole
decr RPF, incr GFR, incr FF
What is the effect of prostaglandin on RPF/GFR/FF? Why is this?
prostaglandins dilate afferent arterioles
incr RPF, incr GFR, FF constant
What is the threshold of glucosuria? When are transporters fully saturated?
threshold- 200mg/dL
saturated- 375 mg/dl
What presents as a pellagra-like disease with neutral amminoaciduria?
Hartnup disease
What is the treatment of Hartnup disease?
High protein diet and nicotinic acid
What does effect does Ang II have on kidney absorption?
PCT- stimulates Na/H exchange- incr abs Na, H20, HCO3
What do loop diuretics work on?
NaKCC of thick ascending loop of Henle
How do loop diuretics affect absorption of Mg, Ca?
diminish + potential in thick ascending limb
Mg2+, Ca2+ no longer diffuse down gradient (decr reabsorption)
What are the effects of PTH on the kidney?
inhibit Na/PO4 cotransport in PCT
incr Ca/Na exchange in DCT
What renal tubular defect presents as metabolic acidosis, glucosuria, amnioaciduria?
Fanconi syndrome
What is defective in Fanconi syndrome?
Reabsorptive defect in PCT
What renal tubular defect presents as hypokalemia, metabolic alkalosis, and hypercalciuria?
Bartter syndrome
What renal tubular defect presents as hypokalemia, metabolic alkalosis, no hypercalciuria?
Gitelman syndrome
What renal tubular defect presents as hypertension, hypokalemia, metabolic acidosis, decr aldost?
Liddle syndrome
What is the treatment of Liddle syndrome?
Amiloride
What is defective in Bartter syndrome?
Na/K/CC in thick ascending loop of Henle
What is defective in Liddle syndrome?
Incr Na+ reabsorption in distal and collecting tubules (aut dom- incr ENac activity)
What is defective in Gitelman syndrome?
Reabsorptive defect of NaCl in DCT
What is the autonomic stimulation of the kidney?
Incr sympathetic tone (B1 receptors)
incr renin secretion
What effect does AT II have on baroreceptor reflect?
limits reflex bradycardia
What is the stimulus and effect of ANP?
stimulus- incr volume in atria
effect- relaxes smooth muscle via cGMP- incr GFR, decr renin
What cells secrete EPO?
interstitial cells in peritubular capillary bed
What is the effect of insulin on K+ levels? What is the mechanism?
Shifts K+ into cell via incr activity of Na/K ATPase (INsulin, K+ IN cell)
What is the effect of digitalis on K+?
shifts out of cell- causes hyperkalemia
What is the effect of B-adrenergic stimulus on K+ levels?
B-adrenergic antag- K+ out of cell
B-adrenergic agonist- K+ into cell
What does a wide QRS and peaked T wave indicate?
Hyperkalemia
What does U waves and flattened T waves indicate?
Hypokalemia
Alteration in what electrolyte causes tetany and torsades de pointes?
hypomagnesemia
Alteration in what electrolyte causes decr DTRs, bradycardia, hypotension, hypocalcemia?
Hypermagnesemia
Alteration in what electrolyte causes irritability, stupor, coma?
high serum Na
Alteration in what electrolyte causes nausea, malaise, stupor, coma?
low serum Na
Alteration in what electrolyte causes tetany, seizures, prolonged QT?
low serum Ca
What is the henderson-hasselbach equation?
pH=6.1+ log[HCO3]/0.03PCO2
What is Winter’s formula?
PCO=1.5[HCO3]+8+/-2
predicts mixed acid base disorder
How is an anion gap calculated?
AG=Na-(Cl+HCO3)
Normal=8-12
What are the effects of salicylates on arterial pH?
early- respiratory alkalosis
late-anion gap metabolic acidosis
Compare Type 1, 2, and 4 renal tubular acidosis
Type 1- distal, pH > 5.5
defect in ability of a-intercalatd cells to secrete H+
Type 2- proximal, pH<5.5
defect in proximal tubule HCO3- reabsoprtion
Type 4- hypoaldosteronism, aldost resistance or K+ sparing diuretic
What do fatty casts indicate?
Nephrotic syndrome
What do granular casts indicate?
acute tubular necrosis
What do waxy casts indicate?
advanced renal disease/ chronic renal failure
What do hyaline casts indicate?
Can be normal
often seen in concentrated urine
Describe findings for nephrotic syndrome vs nephritic syndrome
nephortic- massive proteinuria, hyperlipidemia, fatty casts, edema
nephritic- hematuria, RBC casts in urine (inflammatory process)
Nephrotic syndrome that presents with segmental sclerosis and hyalinosis
focal segmental glomerulosclerosis
Nephrotic syndrome that presents with diffuse capillary and GBM thickening, spike and dome appearance with subepithelial deposits
Membranous nephropathy
Nephrotic syndrome that shows apple-green birefringence with Congo-red stain
Amyloidosis
Nephrotic or nephritic syndrome that shows subendothelial immune complexes, tram-track appearance
Type I membranoproliferative glomerulonephritis
Nephrotic or nephritic syndrome that shows intramembranous IC deposits (“dense deposits”)
Type II membranoproliferative glomerulonephritis
Nephrotic syndrome that shows mensangial expansion, GBM thickening, eosinophilic nodular glomerulosclerosis
Diabetic glomerulonephropathy
What is the pathogenesis of diabetic glomerulonephropathy (2 parts)
NEG of GBM: incr permeability/thickening
NEG of efferent arterioles: mesangial expansion (incr GFR)
What kidney syndrome is associated with HBV and HCV?
Type I MPGN
What kidney syndrome is associated with C3 nephritic factor?
Type II MPGN
What is the etiology of Goodpasture syndrome?
Type II hypersensitivity
Ab against GBM, alveolar BM
What type of immune reaction is acute poststreptococcal GN?
Type III hypersensivity
Presents with peripheral and periorbital edema, dark urine, hypertension
acute poststreptococcal GN
Presents with a cresent-moon shape in glomerulus
RPGN
What is the defect in Alport syndrome?
Type IV collagen defect
What presents as glomerulonephritis, deafness, eye problems
Alport syndrome
What is the treatment of Uric acid kidney stones?
alkalinization of urine
What is the treatment of cystine kidney stones?
alkalinization of urine
What type of calcium kidney stones are associated with incr, decr pH?
Incr pH- CaPO4
decr pH- Caoxalate
What type of kidney stones are envelope or dumbell shape?
Calcium
What type of kidney stones are coffin lid shape?
Ammonium magnesium phosphate
What type of kidney stones are rhomboid or rosette shape?
Uric acid
What type of kidney stones are hexagonal?
Cystine
How does renal cell carcinoma metastasize? What are common sites?
hematogenously
lung and bone
What gene deletion is associated with renal cell carcinoma?
deletion on chromosome 3
hereditary=VHL
What is the underlying cause of squamous cell carcinoma of bladder?
chronic iritation– squamous cell metaplasia
schistosoma hematobium, smoking
Describe the pathology of renal oncocytoma
large eosinophilic cells with abundant mitochondria, no perinuclear clearing
What infection is associated with hemorrhagic cystitis?
adenovirus
What areas are spared in acute glomerulonephritis?
glomeruli and vessels
Presents as thyroidization of the kidney
chronic pyelonphritis
What areas of the kidney (specifically) are most susceptible to ischemic vs nephrotoxic damage?
ischemic: proximal tubule, thick ascending limb
nephrotoxic: proximal tubule
Compare BUN/Cr and FENa for Prerenal, intrinsic renal, and postrenal azotemia
Prerenal: BUN/Cr >20, FENa 2%
Postrenal: >15, >1-2%
Compare simple vs complex renal cysts
Simple- outer cortex, filled with ultrafiltrate- often benign/incidental
complex cysts- septated, enhanced, solid components- require follow up (risk RCC)
What is the inheritance and genetic assoc of ADPKD?
Aut Dom
PKD1- Chr 16
PKD2- Chr 4