Renal, electrolytes

Question 1

In a normal pregnancy, when is the highest growth velocity (g/kg)?

Answer 1

28-32 weeks

Question 2

In a normal pregnancy, what is the growth rate in the 3rd trimester?

Answer 2

gain 30-35 g a day until 32-34 weeks when it decreases after

Question 3

At what weeks of gestation do infants gain the most weight in g/day?

Answer 3

32-36 weeks, gain ~30 g/day

Question 4

When does the pronephros disappear?

Answer 4

4th week of GA

Question 5

What structures form from the mesonephros?

Answer 5

vas deferens, seminal vesicles, and epididymis

Question 6

What tissue types does the kidney come from?

Answer 6

mesodermi

Question 7

What happens if there is unilateral dysgenesis of the mesonephros?

Answer 7

dysgenesis of the unilateral kidney and gonad

Question 8

What structures from the kidney and at what gestation does this start?

Answer 8

metanephros, starts at 5th week GA

Question 9

When do the first nephrons appear?

Answer 9

8th week

Question 10

When is nephrogenesis complete?

Answer 10

34-36 weeks

Question 11

What does fetal growth restriction do to the number of nephrons in the kidney?

Answer 11

reduces it

Question 12

How does renal agenesis occur?

Answer 12

the uteretic bud fails to develop.

Question 13

When does the fetus start to produce urine?

Answer 13

10-12 weeks; is 5 ml/hr by 20 weeks and 50 mL/hr at 40 weeks. At 20 weeks, the amniotic fluid is 90% urine

Question 14

When does the neonatal kidney reach adult concentrating ability?

Answer 14

6-12 months of age

Question 15

What are the 4 factors that reduce the premature infant from concentrating the urine?

Answer 15

tubule insensitivity to vasopressin, short loop of Henle, low osmolality of medullary interstitium (secondary to limited Na reabssorption in the thick ascending loop); low serum urea

Question 16

Why do preterm infants have an increased [Cr] in the first few weeks of life compared to terms?

Answer 16

preterm infants have greater reabsorption of filtered creatinine in baby renal tubules therefore, preterm infant have a decreased Cr clearance 2/2 impaired GFR

Question 17

What syndromes are a/w renal agenesis?

Answer 17

VATER/VACTERL, CHARGE, brachio-oto-renal, Jeune syndrome, T13,T18, T21

Question 18

What is the most common cause of obstructuve uropathy in males?

Answer 18

posterior urethral valves; caused by a congenitall membrane that obstructs the urethra

Question 19

What is the most common cause of congenital hydronephrosis?

Answer 19

UPJ obstruction; no dilated ureter on imaging

Question 20

What is the second most common cause of congenital hydronephrosis?

Answer 20

UVJ obstruction: secondary to deficient development if the ureter or a ureterocoele (an outpouching of the ureter into the bladder); will see a dilated ureter in imaging

Question 21

non-anion gap metabolic acidosis, low K, FTT, and polyuria- whats the Dx?

Answer 21

RTA type I or Type 2

Question 22

Explain the pathophys behind RTA type 1. What’s the urine pH ? What’s the treatment?

Answer 22

aka Distal RTA, cannot secrete acid (H+) in the DCT; alkaline urine the pH> 5.5; Tx bicarb or citrate

Question 23

Explain the pathophys behind RTA type 2. What’s the urine pH ? What’s the treatment?

Answer 23

AKA proximal RTA, cannot absorb bicarb but normal acid secretion, pH acidic (<5.3, which is normal); Recover by toddler to school age. Tx Bicarb or citrate

Question 24

Urine pH < 5.5, hyperkalemia, hyperchloremic metabolic acidosis. What is the Dx?

Answer 24

type 4 RTA

Question 25

Labs show decreased Na, increased K, metabolic acidosis, increased aldosterone, increased renin. Prenatally, the baby had polyhydramnios. What's the Dx?

Answer 25

pseudohypoaldosteronism. X-link recessive

Question 26

Labs with decreased Na and Cl, increased renin, metabolic acidosis, increased K, decreased urine aldosterone. What the diagnosis and what is it a/w?

Answer 26

Aldosterone deficiency; a/w Addison's disease and CAH

Question 27

Labs show increased urine aldosterone, decreased NaCl (salt wasting), metabolic acidosis, increased K. What's the diagnosis>

Answer 27

pseudohypoaldosteronism

Question 28

Flank mass, hematuria and thrombocyopenia. Name the Dx?

Answer 28

Renal vein thrombosis

Question 29

What is the most common cause of neonatal HTN?

Answer 29

Renal artery thrombosis

Question 30

Which region of the kidney does acetazolamine (carbonic anhydrase inhibitor) act upon?

Answer 30

proximal convoluted tubule

Question 31

Which region of the kidney does furosemide act upon?

Answer 31

thick ascending loop of Henle

Question 32

What region of the kidney do thiazide duiretics work on?

Answer 32

distal convoluted tubule

Question 33

What region of the kidney do aldosterone antagonists (like spironolactone) work?

Answer 33

Collecting duct. Remember it is a postassium sparking diuretic

Question 34

What kind of drug us amiloride?

Answer 34

ENaC channel blocker, K sparing duiretic, works on the collecting duct

Question 35

Proteinuria, hypoalbinemia and edema represent what sydrome?

Answer 35

congenital nephrotic syndrome

Question 36

Name the 5 clinical findings for congenital nephrotic syndrome

Answer 36

immunodeficient (loss of igG); iron deificent (loss of transferrin); hyperlipidemia( loss of apoproteins and lipoprotein lipase which leads to elevated triglycerides), hypercoaguable (loss of ATIII), hypothyroid (loss of TBG)

Question 37

This kind of congenital nephrotic syndrom presents within the first month of life, is autosomal dominant, has an increased risk of preterm delivery and SGA, with a large placenta and increased AFP

Answer 37

Finnish congenital nephrotic syndrome

Question 38

Define mild AKI

Answer 38

increase 0.3 mg/dL within 48 hours, 1.5-1.9x baseline within 7 days, UOP < 0.5 ml/kg/hr for 6-12 hours

Question 39

Define moderate AKI

Answer 39

increase 2.0-2.9 from baseline, UOP < 0.5 ml/kg/hr for = or > 12hours

Question 40

Define severe AKI

Answer 40

increase of 3.0 x Cr from baseline OR Cr >/= 2.5 mg/dL OR dialysis; < 0.3 ml/kg/hr for >/= 24 hours or anuria for >/= 12 hours

Question 41

What does a decreased TRP (tubular reabsorption of phos) tell you in the presence of hypophosphatemia?

Answer 41

renal defect in phosphate reabsorption

Question 42

What is the most common cause of urinary tract dilatkon on antenatal US?

Answer 42

transient/ physiologic

Question 43

What are the direct effects of vasopressin?

Answer 43

renal water absorption and increasing blood pressure. Do NOT have a direct effect on renal sodium absorption or urine output; it is secreted by the fetal pituitary as early as 11 weeks; the fetal nephron is less sensitive to vasopressin than the adult

Question 44

What vitamin is important for pulmonary epithelial growth and cellular differentiation?

Answer 44

Vit A

Question 45

Why do patients with RTA have poor growth?

Answer 45

direct effect of serum acid leading to a decreased release of growth hormone and less drive to feed

Question 46

Congenital nephrotic syndrome has been a/w what infections?

Answer 46

toxo, rubella, CMV, syphili, HSV, HIV, Hep B

Question 47

Lowe syndrome is also known as?

Answer 47

oculocerebrorenal syndrome. Its an x-linked recessive disorder that affects the enzymatic function of the golgi apparatus.

Question 48

This syndrome presents with cataracts, low tone, severe mental deficiency, kidney disease, and cryptorchidism

Answer 48

Lowe syndrome

Question 49

What syndrome has elevated maternal and amniotic AFP with increased nucleotide pyrophosphatase in skin fibroblasts?

Answer 49

Lowe syndrome

Question 50

Infant has triangular facies, protruding ears, large eyes with strabismus and a drooping mouth. Whats the syndrome and what electrolyte abnormalities do you expect to see?

Answer 50

Barter syndrome, will see hypokalemia, metabolic alkalosis, hypercalciuria. It is a disorder of the loop of Henle involving Na, Ka and Cl transport. Will also have hypercalciuria and nephrocalcinosis. Affected infants may develop dehydration and hypotension related to severe salt wasting. Treat with Na and K replaement and monitor fluid balance

Question 51

What is the most common cause of acute renal failure in the neonate?

Answer 51

HIE

Question 52

What are indications for dialysis in a newborn?

Answer 52

Acidosis (metabolic), electrolyte issues (hyperkalemia, hyperphosphatemia, hypocalcemia, hyponatremia with volume overload), inability to provide adequate nutrition, overload with fluids, uremia. Notice NOT elevated Cr but that will often coincide with these indications

Question 53

Will the infant born to a mother with vit D defiency be born with low blood calcium levels?

Answer 53

NO. There is an increase is maternal intestinal absorption in the first two trimesters that is independent of the vit D so the fetus will have normal blood calcium levels and a normal skeleton at birth

Question 54

What happends to the blood flow to the kidneys during birth?

Answer 54

drastically decreases. 25% of CO goes to kidneys and then due to hemodynamic changes during and after birth it decreases to 5%

Question 55

When does the GFR reach adult levels?

Answer 55

2 years

Question 56

In infants with Barter syndrome, what are the levels of renin and aldosterone? What about parathyroid hormone?

Answer 56

both increased, but parathyroid hormone is normal despite hypercalciuria