Genitourinary System

Genitourinary (GU) System Quick Study Guide

Structures of the GU System

Remember:

  • 🫘 Kidneys

  • ➡ Ureters

  • 🫙 Bladder

  • 🚽 Urethra

  • Reproductive (internal & external genital structures)

Kidney Development

Timeline

  • 3 weeks gestation: Kidneys begin forming.

  • 10 weeks: Urine production begins.

  • Birth: Kidneys work but are not fully efficient.

  • Age 2: Kidneys reach adult-level filtration (GFR).

NCLEX Tip: Newborn kidneys function, but they cannot concentrate urine as well as adults.

Functions of the Kidneys

Think of the kidneys as the body's filter and balance center.

They:

✅ Filter waste from blood

✅ Maintain fluid balance

✅ Maintain electrolyte balance

✅ Control blood pressure

✅ Help regulate hormones

Nephron = Functional Unit of the Kidney

The nephron is the kidney's filtering unit.

There are 3 major steps to making urine.

1. Glomerular Filtration

Location:
Glomerulus inside Bowman's capsule

What happens?

Blood enters the glomerulus.

The following are filtered out:

  • Water

  • Electrolytes

  • Waste products

The following stay in the bloodstream:

  • ❌ Proteins

  • ❌ Blood cells

Memory Trick:
"Good stuff stays, waste goes."

2. Tubular Reabsorption

Now the body asks:

"Do I still need this?"

If YES:

  • Water

  • Electrolytes

  • Nutrients

are reabsorbed back into the blood.

Purpose: Prevent losing important substances.

3. Tubular Secretion

Now the body asks:

"What extra waste still needs to leave?"

Extra substances are secreted into the tubules:

  • Creatinine

  • Urea

  • Excess electrolytes

  • Excess water

These become urine.

Urine Pathway (Know This!)

Blood
⬇

Glomerulus
⬇

Bowman's Capsule
⬇

Renal Tubules
⬇

Collecting Duct
⬇

Renal Pelvis
⬇

Ureter
⬇

Bladder
⬇

Urethra
⬇

Outside the body

Easy Memory Trick:
Kidney → Ureter → Bladder → Urethra
(KUBU)

Blood Flow Through the Kidney

Blood enters:

➡ Renal artery
➡ Glomerulus

Blood leaves:

➡ Renal vein

NCLEX Must-Know Points

Glomerular Filtration

  • Filters water, electrolytes, and waste

  • Does NOT filter proteins or blood cells

Tubular Reabsorption

  • Returns needed water and electrolytes to the bloodstream

Tubular Secretion

  • Adds extra waste into urine

Kidneys Regulate

  • Fluid balance

  • Electrolytes

  • Blood pressure

  • Hormones

  • Waste removal

Easy Memory Tricks

Kidneys = FEB HW

F = Filter waste

E = Electrolytes

B = Blood pressure

H = Hormones

W = Water balance

Nephron Steps

F → R → S

F = Filtration

R = Reabsorption

S = Secretion

Think:

Filter → Reclaim → Send Away

NCLEX Practice Questions

1. Which structure is the functional unit of the kidney?

A. Ureter

B. Bladder

C. Nephron

D. Urethra

✅ Answer: C

2. During glomerular filtration, which substances normally remain in the bloodstream?

A. Water

B. Electrolytes

C. Proteins and blood cells

D. Urea

✅ Answer: C

3. Tubular reabsorption primarily does which of the following?

A. Removes blood cells

B. Returns needed water and electrolytes to the blood

C. Produces red blood cells

D. Stores urine

✅ Answer: B

4. Which process secretes excess creatinine and urea into the urine?

A. Filtration

B. Reabsorption

C. Tubular secretion

D. Diffusion

✅ Answer: C

5. Place the urine pathway in the correct order.

A. Bladder → Kidney → Ureter → Urethra

B. Kidney → Urethra → Bladder → Ureter

C. Kidney → Ureter → Bladder → Urethra

D. Kidney → Bladder → Urethra → Ureter

✅ Answer: C

🌟 Last-Minute Memory Box

  • 🫘 Nephron = Functional unit of the kidney

  • Filtration = Waste leaves the blood

  • Reabsorption = Needed substances return to the blood

  • Secretion = Extra waste enters urine

  • Proteins & blood cells stay in the bloodstream

  • Kidney functions: Fluid balance, electrolytes, blood pressure, hormones, and waste removal

  • Urine flow: Kidney → Ureter → Bladder → Urethra

Pediatric GU Cancers (Wilms Tumor & Germ Cell Tumors) Study Guide

Overview

The 2 most common pediatric GU cancers are:

  1. Wilms Tumor (Nephroblastoma) → Kidney cancer

  2. Germ Cell Tumor (GCT) → Tumors from abnormal primordial germ cells

Pathophysiology

Cancer develops because:

  • Gene mutations cause uncontrolled cell growth.

  • Pediatric cancers are usually genetic, NOT lifestyle-related.

Wilms Tumor

  • Also called Nephroblastoma

  • Begins inside the kidney

  • Can affect one or both kidneys

  • Most common kidney cancer in children

Remember:

Wilms = Kidney

Germ Cell Tumors (GCT)

Normal Development

  • Primordial germ cells (PGCs) form during fetal development.

  • They normally migrate to:

    • Testes

    • Ovaries

Abnormal Development

Some PGCs fail to migrate correctly during fetal development, remain in other parts of the body, and later develop into tumors.

NCLEX Tip

GCTs develop because primordial germ cells fail to migrate properly during fetal development.

Common GCT Locations

In young children

  • Head

  • Neck

  • Mediastinum

  • Retroperitoneum

  • Sacrococcyx

In adolescents

  • Testicles (most common)

Memory Trick:
"Head to Tail"

  • Head

  • Neck

  • Retroperitoneum

  • Sacrococcyx

  • Testicles

Causes (Etiology)

Childhood cancer is usually caused by:

✅ Genetic mutations

NOT usually caused by:

  • Diet

  • Pollution

  • Sugary drinks

  • Long-term environmental exposure

Risk Factors

Wilms Tumor

About 90% have no known cause.

Risk factors:

  • Family history

  • WAGR syndrome

  • Beckwith-Wiedemann syndrome

Germ Cell Tumors

Biggest risk factor:

✅ Cryptorchidism (undescended testicle)

Other risks:

  • Family history

  • Klinefelter syndrome

  • Turner syndrome

  • Swyer syndrome

Epidemiology

Wilms Tumor

  • Most common pediatric GU cancer

  • About 650 cases/year

  • Usually occurs before age 5

  • Excellent prognosis with treatment

Germ Cell Tumors

Two age peaks:

Peak #1

Birth–4 years

  • Usually outside the gonads

Peak #2

Puberty

  • Mostly adolescent males

  • Usually testicular cancer

Clinical Manifestations

Wilms Tumor

Hallmark Sign

⭐ Painless abdominal/flank mass

Usually:

  • Nontender

  • Firm

Other symptoms:

  • Hematuria

  • Hypertension

  • Hypercalcemia

  • Rare:

    • Fever

    • Weight loss

    • Poor appetite

Memory Trick:
Wilms = Waist lump

Germ Cell Tumor

Hallmark Sign

⭐ Painless testicular lump

Other symptoms:

  • Scrotal swelling

  • Feeling of heaviness

  • Dull ache

NOT usually severe pain

Diagnosis

Cancer workup includes:

  • CBC

  • Kidney/Liver function tests

  • Ultrasound

  • CT scan

  • MRI

  • PET scan

Gold Standard

⭐ Biopsy

EXCEPTION

Wilms Tumor

❌ No biopsy before surgery

Reason:
Risk of rupturing the tumor, spreading cancer cells.

Treatment

Wilms Tumor

  1. Nephrectomy (remove kidney)

  2. Chemotherapy

  3. Radiation (rare)

Nursing Priority

🚫 DO NOT palpate the abdomen

Reason:
May rupture the tumor.

Many hospitals place a sign:

"Do Not Palpate Abdomen."

Testicular Germ Cell Tumor

Treatment:

  • Radical orchiectomy (remove testicle)

  • Sometimes partial orchiectomy

  • Chemotherapy if needed

Late Effects of Chemotherapy

Know these!

  • Chronic kidney disease

  • Peripheral neuropathy

  • Hearing loss

  • Cardiovascular disease

  • Hypertension

  • Lung disease

  • Metabolic syndrome

  • Hypogonadism (↓ sex hormones/fertility)

Psychosocial Effects

Cancer affects:

  • Self-esteem

  • Friendships

  • School attendance

  • Independence

  • Family relationships

Adolescents may struggle with:

  • Body image

  • Fertility concerns

  • Isolation

Developmental Considerations

Hospitalization can cause:

  • Missed school

  • Delayed milestones

  • Reduced socialization

  • Neurocognitive delays

  • Fatigue

  • Infertility later in life

Nursing Care

Before surgery (Wilms)

✅ Don't palpate abdomen

Monitor:

  • Hematuria

  • Pain

  • BP

  • I&O

  • Nutrition

Educate family:

  • Repeat explanations often

  • Use simple language

  • Encourage questions

Child-Friendly Care

Promote:

  • Play

  • Child life specialists

  • Normal routines

  • Age-appropriate explanations

  • Family involvement

Health Promotion

Teach:

Adolescent males should perform:
✅ Monthly testicular self-exams

Avoid:

  • Smoking

  • Alcohol

  • Drugs

  • Carcinogens

Client Education

After Wilms nephrectomy:

Since the child has one kidney:

❌ No contact sports
(Boxing, football, wrestling, etc.)

Continue:

  • Follow-up appointments

  • Healthy lifestyle

  • Avoid smoking/drugs

NCLEX Must-Know Differences

Wilms Tumor

Germ Cell Tumor

Kidney

Testicle (adolescents)

Usually under age 5

Usually adolescence

Painless abdominal mass

Painless testicular lump

Hematuria

Scrotal swelling/heaviness

Nephrectomy

Orchiectomy

Never biopsy before surgery

Biopsy usually performed

Don't palpate abdomen

Perform testicular assessment

Easy Memory Tricks

Wilms = WAK

W = Waist/abdominal mass

A = Abdomen Do NOT palpate

K = Kidney

Germ Cell Tumor = TEST

T = Testicle

E = Embryonic (primordial germ cells)

S = Scrotal swelling

T = Teen boys

NCLEX Practice Questions

1. What is the hallmark sign of Wilms tumor?

A. Painful urination

B. Tender abdominal mass

C. Painless abdominal/flank mass

D. Severe abdominal pain

✅ Answer: C

2. The greatest risk factor for developing a germ cell tumor is:

A. Obesity

B. Hypertension

C. Cryptorchidism

D. Smoking

✅ Answer: C

3. Why is a biopsy NOT performed before surgery for Wilms tumor?

A. It is unnecessary

B. It causes infection

C. It may rupture the tumor and spread cancer cells

D. Children cannot tolerate biopsy

✅ Answer: C

4. Which finding is most consistent with testicular germ cell tumor?

A. Painful scrotum

B. Fever

C. Painless testicular mass

D. Dysuria

✅ Answer: C

5. A nurse is assessing a child with suspected Wilms tumor. Which action should be avoided?

A. Measure BP

B. Assess urine output

C. Auscultate bowel sounds

D. Palpate the abdomen

✅ Answer: D

🌟 Last-Minute NCLEX Review

  • Wilms tumor = Kidney cancer (children <5 years)

  • Hallmark: Painless abdominal/flank mass

  • Never palpate the abdomen with suspected Wilms tumor

  • No biopsy before Wilms surgery due to rupture risk

  • Treatment: Nephrectomy + chemotherapy

  • Germ cell tumors arise from misplaced primordial germ cells during fetal development

  • Biggest GCT risk factor: Cryptorchidism

  • Hallmark of testicular GCT: Painless testicular lump with possible scrotal swelling/heaviness

  • Gold standard for most cancers: Biopsy (except Wilms)

  • After nephrectomy: Avoid contact sports because the child has one functioning kidney.