Renal, Urinary Systems and Electrolytes

Question 1

Treatment:

Primary Enuresis

Answer 1

1. Behavior modifications
2. Alarm therapy
3. Desmopressin (first-line): can provide immediate relief for stressed families when options 1 & 2 have failed, but has a high relapse rate if used alone.

Question 2

Which patients should have a voiding cystourethrogram as a part of the work up for a first febrile UTI?

Answer 2

VCUG is not reccommended for first febrile UTI in children younger than 2 unless:

1. renal ultrasound shows abnormalities
2. patient is a neonate
3. recurrent UTIs

Question 3

What is the work-up and treatment for first febrile UTI in a child younger than 2 years?

Answer 3

1. renal and bladder ultrasound

2. Treat with 1-2 weeks of antibiotics

Question 4

What is the most common cause of urinary tract obstruction in newborn boys?

Answer 4

Posterior urethral valves

Question 5

Diagnosis:

Posterior urethral valves on prenatal ultrasonography

Answer 5

1. bladder distension
2. bilateral hydroureters
3. bilateral hydronephrosis

Question 6

What are the major complications of urinary tract obstruction in utero?

Answer 6

Low urine production –> Oligohydraminos –> pulmonary hypoplasia –> respiratory distress

Question 7

What is the most common cause of nephrotic syndrome in adolescents and adults?

Answer 7

Membranous nephropathy

Question 8

Define nephrotic syndrome.

Answer 8

1. edema
2. proteinuria
3. hypoalbuminemia

Question 9

Which vaccine preventable virus is associated with an increased risk for membranous nephropathy in adolescents and adults?

Answer 9

Active Hepatitis B infection

*Vaccination reduces this risk.

Question 10

What is a common presenting sign of new-onset type 1 diabetes mellitus in children?

Answer 10

nocturnal enuresis

Question 11

Clinical manifestation:

Polyuria
Polydipsia

Answer 11

diabetes mellitus

In pediatrics these are common presenting symptoms of new onset type 1 diabetes mellitus.

Question 12

What is a potential sequelae of severe vesicoureteral reflux?

Answer 12

recurrent or chronic pyelonephritis

Question 13

What are the major complications of recurrent or chronic pyelonephritis?

Answer 13

1. parenchymal scarring
2. hypertension
3. renal insufficiency

Question 14

Diagnosis:

vesicoureteral reflux

Answer 14

Definitive diagnosis is made by voiding cystourethrogram.

Question 15

What renal complications are associated with sickle cell trait?

Answer 15

1. painless hematuria
2. urinary tract infections
3. renal medullary cancer

Question 16

How do you differentiate transient proteinuria from persistent proteinuria?

Answer 16

Perform a urine dipstick on 3 separate occasions to differentiate between transient and persistent proteinuria.

Question 17

Clinical Manifestations:

Henoch-Schonlein purpura

Answer 17

1. palpable purpura on the lower extremities
2. arthralgias
3. abdominal pain
4. renal disease

Question 18

Diagnosis:

Immunofluroescence microscopy in Henoch-Schonlein purpura

Answer 18

IgA deposition in the kidney

Question 19

Pathogenesis:

Henoch-Schonlein purpura

Answer 19

IgA mediated vasculitis of the small vessels

Question 20

What is the work up for a suspected UTI in a child?

Answer 20

1. Urine Analysis
2. Urine culture

*Patients in diapers should undergo straight catheterization to obtain a sterile specimen and avoid contamination with stool or skin flora.

Question 21

Clinical Manifestation:

1. recurrent hematuria
2. sensorineural deafness
3. family history of renal failure

Answer 21

Alport’s syndrome

Question 22

Clinical Manifestation:

4 week old infant with projectile, nonbilious vomiting that occurs after each feed.

Answer 22

Pyloric stenosis

Question 23

Diagnosis:

Electrolyte abnormalities associated with pyloric stenosis

Answer 23

1. hypochloremia
2. hypokalemia
3. metabolic acidosis (low bicarbonate)

“hypochloremic, hypokalemic metabolic acidosis”

Question 24

Treatment:

Pyloric stenosis

Answer 24

pyloromyotomy

*Be sure to correct the electrolyte balance (“hypochloremic, hypokalemic metabolic acidosis”) prior to surgery!

Question 25

What is the most common age range for presentation with pyloric stenosis (projectile, nonbilious vomiting after each feed)?

Answer 25

3-5 weeks

Question 26

Clinical Manifestation:

Renal Tubular acidosis

Answer 26

failure to thrive

Question 27

Why do patients with renal tubular acidosis present with failure to thrive?

Answer 27

They have a chronic, normal anion gap metabolic acidosis.

Question 28

Pathogenesis:

Renal Tubular Acidosis

Answer 28

1. defect in hydrogen excretion in the kidney

2. defect in bicarbonate resorption in the kidney

Question 29

Treatment:

Renal Tubular Acidosis

Answer 29

Oral bicarbonate replacement

Question 30

Pathogenesis:

most common cause of UTI in females

Answer 30

bacteria ascends into the bladder from vaginal introitus

Question 31

Why is sexual intercourse an important risk factor for UTIs in women?

Answer 31

Sexual intercourse allows for the introduction of uropathogens into the urethra.

Question 32

What risk factor is associated with recurrent cystitis in toddlers? Describe the pathogenesis.

Answer 32

Chronic constipation is a important risk factor for recurrent cystitis in toddlers.

impacted stool –> rectal distension –> bladder compression –> incomplete voiding –> urinary stasis –> infection

Question 33

What is the most common cause of nephrotic syndrome in pre-adolescent children?

Answer 33

Minimal change nephropathy

Question 34

Treatment:

Minimal change nephropathy

Answer 34

Steroids (high responsive)

Note, renal biopsy is NOT required for initial diagnosis and is not routinely obtained in patients younger than 10.

Question 35

Treatment:

initial resuscitation for hypovolemic hypernatremia

Answer 35

Isotonic solution (i.e. normal 0.9% saline)