Renal colic

Question 1

What is renal colic?

Answer 1

Pain usually caused by renal calculi.

Question 2

What are the most common sites for stones to get stuck at?

Answer 2

Pelvi-ureteric junction
Pelvic brim
Vesico-ureteric junction
(PTS)

Question 3

Give 3 risk factors for renal colic

Answer 3

1. Male (3:1)
2. 30-50 years old
3. Family history
4. Anatomical abnormalities
5. Hypertension
6. Gout
7. Immobilisation
8. Dehydration
   (PTS)

Question 4

Give 3 things can renal calculi be composed of.

Answer 4

Calcium oxalate/ phosphate (80%)
Struvite (infection) (10%)
Uric acid (usually lucent on KUBXR) (5-10%)

Question 5

Describe the pathophysiology of renal calculi.

Answer 5

Nucleation theory states that renal calculi form from supersaturation of urine with salt/minerals. (PTS)
Anatomical factors, eg spina bifida, horseshoe kidney (embryological fusion of kidneys)
Infection - changes acid-base balance.

Question 6

Give 3 symptoms of renal calculi.

Answer 6

Can be asymptomatic, picked up on a CT for bowel disease.
1. RENAL COLIC sudden severe unilateral loin pain radiating to groin
2.. UTI symptoms: Dysuria, strangury (desire to urinate + severe pain), urgency, frequency.
3. Nausea and vomiting
4. Rigors
(PTS, lecture 19.2.18)

Question 7

Give 3 signs of renal calculi.

Answer 7

1. Haematuria, usually non-visible
2. Patient writhes around in agony
3. recurrent UTIs
   (lecture 19.2.18, PTS)

Question 8

Describe the prevention of renal calculi recurrence.

Answer 8

Prevention of another stone forming:
1. Overhydration
2. Dietary modification - low-salt diet
3. reduce BMI
4. Check calcium - PTH.
5. deacidification of urine to prevent uric acid stones.
Always think about sepsis
(lecture 19.2.18)

Question 9

Give 3 diseases that may be in your differential diagnosis if you suspect renal calculi.

Answer 9

1. Ruptured abdominal aortic aneurysm
2. Diverticulitis
3. Appendicitis
4. Acute pancreatitis
5. Testicular torsion

Question 10

What investigations would you do if you suspect renal calculi?

Answer 10

1. Bloods - FBC, U&E, calcium, phosphate, urate
2. Urinalysis
3. If urinalysis positive, MSU
4. Imaging: NCCT-KUB (99% sensitive), KUBXR (70% sensitive)

Question 11

Describe the management of renal calculi.

Answer 11

1. ABC, anti-emetic, analgesic eg diclofenac
2. Focussed history and examination
3. Antibiotics if infection suspected
   Stones <5mm usually pass spontaneously
   Stones >5mm removed using tamsulosin, lithotripsy or nephrolithotomy.
   If infection + obstruction, urinary stent may be needed.