Nephology

Question 1

Newborn presents with:

• bilateral renal cysts and enlarged kidneys without dysplasia.
• history of oligohydramnios and pulmonary hypoplasia
• Renal ultrasonography:
  
  • bilaterally enlarged kidneys with poor corticomedullary differentiation.
  • The renal cysts cannot be visualized on ultrasonography.

What’s the diagnosis

Answer 1

autosomal recessive polycystic kidney disease (ARPKD)

• mutations in the gene PKHD1
  
  • encodes a protein expressed in the cilia of renal tubular and hepatic bile duct epithelial cells.
• 50% chance of developing end-stage renal disease
• Associated with congenital hepatic fibrosis, abnormalities of bile ducts

Question 2

Newborn presents:

• oligohydramnios
• pulmonary hypoplasia
• renal failure
• Ultrasound: bilateral hydronephrosis
• VCUG: dilated bladder and prostatic urethra

What’s the diagnosis?

Answer 2

Posterior urethral valves

• Diagnosis: Voiding cystourethrography
• Treatment:
  
  • urinary catheter to relieve the obstruction
  • ablation of the valves
• Prognosis: Chronic kidney disease

Antenatal management: none
Buzzwords for UTZ- distended bladder, poor emptying at 30 mins, keyhole appearance

Question 3

Gestational age nephrogenesis continues

Answer 3

until 36 weeks

Question 4

A 3.5 kg, 6-week-old boy is diagnosed with pyloric stenosis after a 3-day history of vomiting. Serum electrolytes show sodium 132 mEq/L, potassium 2.8 mEq/L, chloride 96 mEq/L, and bicarbonate 27 mEq/L. What is the most appropriate fluid to begin intravenous resuscitation for this patient?

Answer 4

Normal saline

• Prolonged vomiting loses gastric fluid rich in both hydrogen and chloride ions, resulting in both metabolic alkalosis and hypochloremia.
• most of the potassium deficit is due to urinary losses triggered by secondary hyperaldosteronism.

Question 5

when to start Na supplement in short bowel syndrome

Answer 5

Urine sodium less than 10mEq/L

less Na in distal tubles, limits ability to correct metabolic acidosis

think of contraction alkalosis, hormone: Aldosterone

Question 6

RTA with nephrocalcinosis (renal stone)

Answer 6

RTA type 1

Distal tubule, cannot secrete H+

Question 7

RTA that affect proximal tubules and cannot reabsorb HCO3

Answer 7

RTA type 2

Question 8

RTA associated with aldosterone (abnormal production or sensitivity), presents with hyperkalemia and hyperchloremia

Answer 8

RTA type IV

Question 9

It is the treatment of choice for DI in neonates

Answer 9

Hydrocholorthiazide

Why not vasopressin: difficulty in accurate dosing and variability in the absorption and action of intranasal and oral preparations- may lead to water intoxication and hyponatremia

Question 10

Different RTAs

Answer 10

Question 11

what are the different congenital renal anomalies

Answer 11

Question 12

the most likely cause of renal agenesis is failure of the development of:

Answer 12

ureteric bud

Question 13

Embryology

Where are the kidneys derived from

Answer 13

Metanephros

Question 14

Embryology

Where does the bladder and urethra come from

Answer 14

Cloaca

Question 15

Quick facts

VUR

Answer 15

Gold standard Dx: VCUG
Prognosis: Grade 1-3 spon resolves by 5 y/o
Antibiotic prophylaxis: yes