Lecture 7 Disturbances in genitourinary function

Question 1

Hormonal functions of the kidneys

Answer 1

1. Renin - helps regulate blood pressure.

2. Erythropoietin - stimulates red blood cell production in the bone marrow.

Question 2

The kidneys convert vitamin D into _

Answer 2

Its active form, calcitriol, which is necessary for calcium metabolism.

Question 3

Approximate bladder capacity (volume) of a child

Answer 3

of oz = Child’s age in years + 1

Question 4

Normal urine specific gravity

Answer 4

1.016 - 1.022

Question 5

Normal urine pH

Answer 5

4.8 - 7.8 (average: 6)

Question 6

Normal blood urea nitrogen (BUN)

Answer 6

5 - 18 mg/dL

Question 7

Urinary tract infection (UTI)

Answer 7

1. The presence of a significant number of microorganisms in the urinary tract, usually caused by ascending bacteria - excludes the distal one-third of the urethra, which is normally colonized by some bacteria.
2. Most common microorganism: E. coli (approximately 80% of UTIs in children).

Question 8

Cystitis

Answer 8

Infection of the bladder.

Question 9

Pyelonephritis

Answer 9

Infection of the kidney.

Question 10

UTIs by age and gender

Answer 10

1. Neonates = roughly equal incidence for both genders.
2. Infants and older = UTIs are 10-30% more frequent in girls.
3. Age 4 = age of maximum incidence for both genders.
4. Girls have an approximately 50% greater recurrence rate than boys.

Question 11

Clinical manifestations of UTIs

Answer 11

1. Infants = fever or hypothermia in neonate; irritability; poor feeding; vomiting; dysuria (painful or burning urination); change in urine odor or color.
2. Children = abdominal or suprapubic pain; frequency, urgency; dysuria; new or increased incidence of enuresis.

Question 12

The most important host factor in determining whether a UTI will occur is _

Answer 12

Urinary stasis - urine provides an excellent medium for the growth of bacteria, fungi, etc.

Question 13

Changes in urine odor or color with UTIs

Answer 13

Urine will appear cloudy or hazy; strands of pus or mucus; “fishy” odor. Pus visible on micro-exam and at least one bacterium visible on Gram stain (in a single drop of urine).

Question 14

Clinical manifestations of pyelonephritis

Answer 14

May appear similar to a UTI. Most common symptoms include fever, back pain, nausea/vomiting, lethargy, poor appetite, and costovertebral angle tenderness.

Question 15

Voiding cystourethrography (VCUG)

Answer 15

Contrast medium injected into bladder through urethral catheter until bladder is full; films taken before, during, and after voiding.

Question 16

Intravenous pyelography (IVP)

Answer 16

1. Intravenous injection of a contrast medium; medium secreted and concentrated by tubules; X-ray films obtained beginning 5 minutes after injection.
2. Usually reserved for situations where there not enough information derived from the other tests.

Question 17

Checking for evidence of pinworms

Answer 17

Pinworms infect the GI tract but may cause vaginitis because they exit at night to lay eggs. At night, apply a strip of tape across the anus; peeling the strip off in the morning will reveal the presence of worms.

Question 18

Antibiotics of choice for UTIs

Answer 18

Bactrim or Septra (trimethoprim-sulfamethoxazole); Amoxil (amoxicillin).

Question 19

Recommended daily fluid intake to prevent UTIs

Answer 19

About 100 mL/kg/day.

Question 20

Recommended voiding frequency to prevent UTIs

Answer 20

At least every 2 hours.

Question 21

Vesicoureteral reflux (VUR)

Answer 21

1. The retrograde flow of bladder urine into the ureters; increases the chance for and perpetuates infections.
2. Familial pattern: Increased incidence among siblings; increased incidence among children of parents who have had VUR.
3. Interventions: Low-dose antibiotic therapy (must finish entire course of antibiotics even if asymptomatic) and frequent urine cultures. Surgery used in severe cases.

Question 22

Glomerulonephritis

Answer 22

1. A group of kidney diseases where the glomerulus is injured - capillaries of glomerulus are inflamed.
2. Occurs from infection, systemic disease process, or as a primary defect in the glomerulus itself.
3. Manifestations: Periorbital edema - especially in the morning, cola- or tea-colored urine (hematuria), decreased urine output, hypertension, fatigue.

Question 23

Most common form of glomerulonephritis in children

Answer 23

Acute post-streptococcal glomerulonephritis (APSGN), an immune-complex disease which can occur 1-3 weeks after strep infection of the throat or skin.

Question 24

Diagnosis of acute post-streptococcal glomerulonephritis (APSGN)

Answer 24

1. Urinalysis - hematuria, proteinuria, urine specific gravity increased to 1.020.
2. ASO titer level will be increased - indicates a recent strep infection.
3. C3 (serum complement level) will be decreased initially but returns to normal 8-10 weeks after onset of glomerulonephritis.
4. VCUG, renal scan for evidence of scarring, urodynamic studies for voiding dysfunction.

Question 25

The most effective measure for fluid balance in children is _

Answer 25

Monitoring their daily weight (same time, same scale, same amount of clothing).

Question 26

Implementing fluid restrictions in children

Answer 26

Review output (e.g., for the previous 8 hours). For the next 8 hours, the child will only be allowed to have that amount of fluid, plus a small amount for insensible water loss.

Question 27

Treatment of acute post-streptococcal glomerulonephritis (APSGN)

Answer 27

No specific treatment; antibiotics will only be used if there is evidence of a persistent strep infection. Antihypertensives and diuretics may be used (diuretics will *not* be used in cases of severe renal failure).

Question 28

Normal serum creatinine

Answer 28

0.3 - 0.7 mg/dL.

Question 29

Nephrotic syndrome

Answer 29

1. The most common presentation of *glomerular injury* in children. 2. Characterized by *massive proteinuria*, hypoalbuminemia, hyperlipidemia, and edema.

Question 30

Important nursing intervention for children with nephrotic syndrome

Answer 30

Provision of good skin care and frequent turning - these children are prone to skin breakdown.

Question 31

Minimal-change nephrotic syndrome (MCNS)

Answer 31

1. Most common type of nephrotic syndrome in children (about 80%; predominately occurs in school-aged children). 2. Cause is obscure, but is often preceded by a viral upper respiratory infection.

Question 32

Secondary nephrotic syndrome

Answer 32

1. Occurs after or in association with glomerular damage of known etiology. 2. Main presenting symptom of renal disease in *pediatric AIDS*.

Question 33

Congenital nephrotic syndrome

Answer 33

1. Recessive genetic disorder; children are born small for gestational age, with proteinuria and edema present at birth. 2. Fatal by 2 years of age unless the child undergoes dialysis or renal transplantation.

Question 34

Renal tubular disorders

Answer 34

1. One or more abnormalities in specific mechanisms of tubular transport or reabsorption. 2. May be minimally disruptive to renal function or result in major renal failure. 3. *Metabolic disturbances* are the primary manifestations: Failure to thrive, metabolic bone disease, persistent acidosis. Usually these children present with no edema, no blood pressure abnormalities, and their BUN and UA are WNL.

Question 35

Proximal tubular acidosis (Type II)

Answer 35

1. Caused by impaired bicarbonate reabsorption in the proximal tubule. 2. *Fanconi syndrome* - complex form which can be acquired or hereditary, with *growth failure* and tachypnea as the major symptoms.

Question 36

Distal tubular acidosis (Type I)

Answer 36

1. Caused by the inability of the kidney to establish a normal pH gradient between tubular cells and tubular contents. 2. Most characteristic feature is the inability to produce a urinary pH below 6.0 despite the presence of severe *metabolic acidosis*. 3. Therapy involves administration of bicarbonate or citrate to correct imbalances and electrolyte disorders.

Question 37

Nephrogenic diabetes insipidus

Answer 37

1. Characterized by renal tubular resistance to the antidiuretic hormone arginine vasopressin (AVP) - leads to an inability to concentrate urine, with subsequent polyuria and compensatory polydipsia. 2. *May be hereditary* (X-linked recessive) or acquired.

Question 38

Hemolytic uremic syndrome

Answer 38

1. Acute renal disease characterized by the triad of nephropathy, thrombocytopenia and microangiopathic hemolytic anemia. 2. Usually follows an acute GI or upper respiratory infection. 3. A leading cause of acute renal failure in early childhood; primarily occurs between the ages of 6 months and 3 years.

Question 39

Chronic renal failure (CRF) in children

Answer 39

*Most common complaint: growth impairment.* Child presents with *short stature*, especially in combination with polyuria, frequent bouts of dehydration, salt craving, bone deformities, abnormal tooth development, lethargy, anemia, history of upper respiratory infections or glomerulonephritis.

Question 40

Interventions for chronic renal failure (CRF)

Answer 40

1. Nutrition: Provide 100% of RDA for calories; low sodium diet and fluid restriction; vitamin D and water-soluble vitamin supplementation; *possible* phosphorus restriction. 2. Medications: Phosphorus binders (i.e., calcium carbonate) - correction of osteodystrophy; alkalizing agents (i.e., sodium bicarbonate) - correction of acidosis; recombinant human erythropoietin and/or iron supplements often needed to correct anemia. 3. Antihypertensives: Diuretics, beta-blockers and vasodilators may all be used.