Renal Flashcards
Sequence of Potter syndrome?
Pulmonary hypoplasia Oligohydraminios Twisted face Twisted skin Extremity defects Renal failure
What is oligohydraminos?
Causes?
Compression of developping fetus with limb deformities, facial anomalies (low set ears, retrognathia, flattened nose)
Compression of chest and lack of amniotic fluid aspiration into the fetal lungs
Can cause pulmonary hypoplasia
Causes: ARPKD (polycystic kidney disease) Obstructive uropathy bilateral renal agenesis Chronic placental insufficiency
Horeshoe kidney?
Inferior poles of the kidney are fused
Kidney’s function normally
Associated with hydronephrosis (uretropelvic obstruction, renal stones, infection, and chromosomal abnormality)
Associated with Turner’s syndrome, trisomies 13, 18, 21 and renal cancer
Unilateral renal agenesis?
Ureteric bud fails to develp and induce differentiation of metanephric mesenchyme
Complete absense of kidney and ureter
Often diagnosed with ultrasound prenatally
Multicyctic dyplastic kidney?
Ureteric bud fails to differentiare
Creates non functioning kidney consisting of cysts and connective tissue
What is duplex collecting system?
Bifurcation of ureteric bud before it enters the metanephric blastema
Y shaped bifid ureter
Strongly associated with vesicouretal refluc and ureteral obstruction
Increase risk of UTI
Congenital solitary functioning kidney?
Born with only one functioning kidney
Majority asymptomatic with compensatory hypertrophy of the contralateral kidney
Anomalies of the contralateral kidney are common
Which kidney taken during transplant?
Left kidney is taken, because it has a longer renal vein
Afferent vs efferent?
Afferent is arriving
Efferent is exiting
What is the renal blood flow?
Renal artery—segmental artery—interlobar artery—arcuate artery—interlober artery—afferent arterirole —-glomerus—-efferent arteriole—vasa rectal —peritubular capillaries—venous outflow
What is the course of the ureters?
Pass under uterine artery or under vas deferens (retroperitoneal)
Gynecological procedures (ligation of uterine or ovarian vessels) may damage ureter
Cause ureteral obstruction or leak
What are the percentage of the body composions?
(the percentage of body weight of a person)
60% total body water
40% ICF
20% ECF
Plasma volume can be measuredby radiolabeling albumin
Extracellular volume can be measured by insulin or mannitol
Glomerular filtration barrier?
responsible for filtration of plasma according size and net charge
Composed of fenestrated capillary endothelium
Fused basement membrane with heparin sulfate epithelial layer (negative charge and size barrier)
Epithlial layer consisting of podocyte foot processes (negative charge barrier)
What happens in the glomerular filtration barrier during nephrotic syndrome?
Albuinuriea
Hypoproteinemia
Generalized edema
Hyperlipidemia
How to calculate renal clearnace?
Cx (clearance of X)
Ux (urine concentration)
Px (plasma concentration)
V (urine flow rate)
If Cx < GFR (net resoprtion of X)
If Cx > GFR (net tubular secretion of X)
Cx = GFR no net secretion or absorption
How to calculate the volume ofplasma from which the substance is completely cleared per unit of time:
Cx= UxV/Px
What is a normal GFR?
How is GFR affected by stages of the kidney disease?
Normal GFR is 100 ml/minute
Incremental reduction of GFR that define stages of chronic kidney disease
Note: creatinine clearance is an approximate measure of GFR (slightly overestimates GFR because creatinine is moderately secreted by renal tubules
What is effective renal plasma flow?
Can be estimated using para-aminohippuric acid (PAH) clearence because between filtration and secretion, there is 100% secretion of all PAH that enters the kidney
eRPF = Upah x V/Ppah = Cpah
r
What is the renal blood flow?
RBF= RPF/ (1-Hct)
What is the plasma blood flow?
1-hematocrit
How does the eRPF compare to the renal plasma flow ?
The eRPF (effective renal plasma flow) underestimates the true renal plasma flow.
How to calculate filtration fraction?
FF= GFR/RPF (RPF is effective renal flow)
Normal FF is 20%
Effect GFR, RPF, and FF with afferent arteriole constriction?
GFR decreases
RPF decreases
No change in the FF (because FF is equal to GFR/RPF
Effect on GFR, RPF and FF if efferent arteriole constriction?
Increase GFR
Decrease RPF
Increase in FF
Effect of GFR, RPF abd FF increase plasma concentration?
Decrease GFR
No change in RPF
Decrease in FF