#6. Urolithiasis - Clinical Picture, Diagnosis

Question 1

What Classification approaches are used for Stones?

Answer 1

1) Chemical Composition
- Calcium Containing Calculi
- Calcium NOT Containing Calculi

2) Location
- Upper / Middle / Lower CALCYX
- Renal Pelvis
- Proximal / Middle / Distal 1/3 of URETER
- Bladder
- Urethra

3) Size
- 5mm / 5 - 10 mm / 10 - 20 mm / over 20

4) X-Ray Characteristics
- Radiopaque = Calcium Oxalate Dihydrate, Monohydrate, Phosphate

• Sometimes Radiopaque / Radiolucent = Struvite / Apatite / Cystine
• Radiolucent = Uric Acid / Ammonium Urate / Xanthine

5) Etiology
- Non Infectious = Calcium Oxalate / Phosphate / Uric Acid

• Infectious = Magnesium Ammonium Phosphate / Carbonate
• Genetic = Cystine / Xanthine

Question 2

Which Stones are Radiopaque?

Answer 2

• Calcium Oxalates
• Phosphate Calculi

Question 3

Which Stones are Radiolucent?

Answer 3

Urate Stones / Calculi are Radiolucent

Question 4

For Which Stones is Infection a Necessary Condition for their Formation?

Answer 4

Magnesium Phosphate Calculi

• They’re found in CHRONIC Urinary Infections such as - Pyelonephritis / Cystitis
• DUE to Urea-Splitting Organisms such as - Proteus / Klebsiella

Question 5

What is the Mechanism of Occurrence of Renal Colic?

Answer 5

• DUE to DISTENDED Fibrous Renal Capsule, RICHLY Innervated by Branches of SYMPATHETIC Plexus of Spinal Cord Segments Th12 - L2
• CAUSED BY Complete / Partial Obstruction of Ureter by MIGRATING Urinary Stone

Question 6

What are the Symptoms of Cast Stones?

Question 7

What are the Symptoms of Renal Colic?

Answer 7

• Strong, sometimes Stabbing, with Intervals of Increasing / Decreasing Colicky Pain
• Located in the Lumbar Region
• Mainly felt in the Costovertebral Angle, radiating along the Ureter, and sometimes towards to Testicle
• Patients are excited to move as they’re constantly moving for a relieving position in the body.

Question 8

What are the Chances for a Stone Measuring 4 - 5mm to pass Spontaneously through the Urinary Tract?

Answer 8

Stones measuring 4 - 5mm have 40 - 50% chance of spontaneous passage

Question 9

A Stone in which Part of the Excretory System is most likely to cause Painful Urges to Urinate with a feeling of Incomplete Micturition?

Answer 9

• URETERAL Lithiasis in the DISTAL Part
• AKA Juxtavesical / Intramural
• Feel a DULL Ache, accompanied by SHORT-TERM Stabbing in the Lower Abdomen / Behind the Symphysis

Question 10

Which Imaging Method is MOST Informative in the Diagnosis of Urolithiasis?

Answer 10

CT is the GOLD STANDARD in Diagnosis of Urolithiasis

• BOTH Radiopaque + Radiolucent Calculi can be visualised

Question 11

Which Stones CANNOT be Found Using CT?

Answer 11

EXCEPT for Calculus CONTAINING INDINAVIR

• Which is a DRUG used to Treat HIV Infections

Question 12

What are the Contraindications for the Use of Intravenous Contrast Agents?

Answer 12

• Patient Hypersensitivity to Contrast Agent
• Renal Failure
• Patients with Renal Colic

Question 13

Does it matter whether the Calculi are Radiopaque or Radiolucent for the Ultrasound Examination?

Answer 13

No, Calculi can either be Radiopaque or Radiolucent (MORE than 5mm), REGARDLESS of Ultrasound Examination

Question 14

What will be found on the Ultrasound in a Patient with an Obstructive Stone in the Middle 3rd of the Ureter?

Question 15

What are the Indications for Retrograde Ureterography in Urolithiasis?

Answer 15

• Calculus Obstruction
• Urethral Trauma

Question 16

What is the Role of Isotope Studies in Urolithiasis?

Answer 16

• Obtains info of the FUNCTIONAL STATE such as - Secretion + Excretion
• Of the 2 Kidneys SEPARATELY

Question 17

What are Phleboliths?

Answer 17

Phleboliths are small, round lumps of calcium that form in a person’s veins

Question 18

What is the Role of MRI in the Diagnosis of Urolithiasis?

Answer 18

MRI Provides a Diagnostic VALUE that is LOW