Renal colic Flashcards

1
Q

What is renal colic?

A

Refers to acute severe loin pain that occurs secondary to a urinary stone.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is another name for urinary stones?

A

urolithiasis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is the peak incidence age for symptomatic urinary stones in men and women?

A

Between 40-60 years in males and late 20’s in females

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Why do patients experience pain (renal colic) when they have a urinary stones?

A

Obstruction to urinary flow within the ureter due to the urinary stones. Also spasms that occur in ureter

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are the signs and symptoms of renal stones?

A

Symptoms
Loin-to-groin pain (sever, sudden onset pain not relived by pain medication- pain is constant but can vary in severity)
(this means pain can radiate from the flank to groin)
Nausea and vomiting
Haematuria
Dysuria (painful urination)
Urgency
Patient is restless to obtain relief from pain
Some are asymptomatic

Signs
Flank tenderness
Haematuria (typically microscopic)
Fever
chills, Rigors
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

List the different types of renal stones

A
Calcium	Oxalate	
Calcium phosphate 
 Urate	
Magnesium Ammonium	 Phosphate (Struvite)
 Cysteine	

Others

  • Xanthine
  • Idinavir
  • Matrix
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Describe the properties of calcium oxalate stones and how they are formed

A
  • Most common type of stone
  • Calcium oxalate is insoluble.
  • Not forming this type of stone depend upon
    inhibitors (citrate, magnesium) Loss of these inhibitors can promote stone formation
  • Shows up on Xrays

Formation -

  • Calcium phosphate crystals accumulate in the Interstitium
  • This leads to the formation of Randall’s plaques (calcification) at the loop of Henle
  • This creates a surface for renal stones to form
  • Renal stones formed in the tubules get stuck at the ducts of Bellini (collecting duct) at the papillary surface (most distal part of the duct)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

There are 2 types of calcium oxalate stones what are they?

A

Dihydrate which are softer (700HU)

Monohydrate which are extremely hard (1500 HU)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Describe the properties of calcium phosphate crystals

A

Associated with 3 conditions:

  • Hyperparathyroidism
  • Distal Renal Tubular Acidosis (Type1)

• Medullar Sponge Kidney
(MSK)

Also associated with urinary stasis & partly with infection
Show up reasonably well on x ray, and are usually quite hard (1200HU)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Describe the properties of urate crystals. Colour, shape, urinary conditions for production.

A
  • Bright yellow stones formed from uric acid in the urine
  • Needle shaped
  • Formation is strongly associated with low PH and high uric acid concentration in the kidneys (idiopathic gout, increased cell turnover in myeloproliferative disease, dehydration)
  • So (400HU) and, dissolvable
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are the different causes of uric acid stones?

A

Metabolic syndromes e.g diabetes
Gout
Dehydration due to malabsorption or chronic diarrhoea
Hyperuricaemia and, therefore, hyperuricosuria which can be caused by -

Myeloproliferative disorders such as leukaemia (increased cell turn over)
Chemotherapy (increased cell turn over)
Haemolytic anaemia (increased cell turn over

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Describe the properties of Magnesium Ammonium Phosphate crystals (struvite)?

A
  • Associated with infections
  • Shows up slightly on X rays
  • Usually relatively soft
    (200-­‐600HU)
  • Often has associations with calcium phosphate crystals
  • usually associated with Staghorn Calculi (due to growing rapidly)
  • Coffine lid appearance
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Which microorganisms are associated with Magnesium Ammonium Phosphate crystals (struvite) and how?

A

Protease-producing microorganisms including Proteus and Klebsiella.

microorganisms are able to convert urea into ammonia which reacts with water increasing the pH of the urine. Increased ammonia and alkaline urine promote stone formation.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are the properties of Cysteine crystals?

A
  • Associated with Cysteinuria
    – gene disease
  • Poorly visible on x-­‐ray & are Hard (1400HU)
  • Produce a white smoke and rotten egg smell when lasered (Hydrogen sulphide)
  • Hexegan shape
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

How are Cysteine crystals treated?

A

medical dissolution

therapy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is a key feature of the matrix urinary stones?

A

Proteinaceous material - a lot like chewing gum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is a key feature of the Idinavir urinary stones?

A

Do not show up on CT

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is the free theory associated the stone formation?

A
The presence of stone constituents in the right amount, and without enough inhibitors, will form stones .
Formation is effected by:
- Concentration of solutes 
- Urine acidity 
- Presence of formation inhibitors
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is the fixed theory regarding renal stone formation?

A

The energy to form a crystal lattice is lower if there is a surface to form them on

Formation effected by:

  • Surface to form lattice on
  • Crystals (other crystals like urate can form a surface)
  • Randall’s plaques (sub urothelial deposits which form a surface)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What are the main inhibitors in renal stone formation? (5)

A

Citrate (calcium citrate is soluble)

Magnesium (magnesium oxalate is soluble)

They prevent calcium oxalate crystals from forming

osteopontin

Nephrocalcin

Tamm Horsfall Protein (THP) (uromodulin)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

From where does the body obtain oxalate?

A
  • The diet
  • endogenous sources in the
    liver as part of glycolate
    metabolism
  • Vitamin C is converted to oxalate
22
Q

Where is oxalate absorbed from and how is absorption prevented? Why is it important for absorption to be inhibited?

A

Oxalate is absorbed mainly from the gut

When calcium binds to oxalate it prevents it from being absorbed

Enhanced intestinal absorption of dietary oxalate leads to elevated renal oxalate excretion

23
Q

What is enteric hyperoxaluria and which conditions can cause it?

A

Enhanced intestinal absorption of dietary oxalate

  • Crohns disease
  • jejunoileal bypass surgery
24
Q

How would calcium supplements help to prevent high levels of oxalate?

A

Very little oxalate is stored so if not bound to calcium it will be absorbed and can lead to hyperoxaluria.

Calcium can be stored in the bones so it is important to ensure there is enough circulating to bind to oxalate

25
Q

List 4 dietary sources of oxalate?

A

Rhubarb, spinach, beetroot, swiss chard, okra, sweet potato, nuts

26
Q

Tamm Horsfall protein acts to prevent renal stones and also prevent infections and UTI’s. How does it accomplish this?

A

It covers crystal structures and prevents them from binding to the renal epithelial cells

Prevents bacteria from binding to epithelium preventing UTI from E.coli

27
Q

What is caused by a mutation in the Tamm Horsfall protein gene?

A

familial juvenile hyperuremic nephropathy

medullary cystic kidney disease 2

both have increased stone
formation/ nephrocalcinosis

28
Q

Which tests would you conduct if someone suspected of having Renal stones?

A
Bedside-
Observations 
ECG
Urinanalysis (blood urine)
Urine dip - WBc/ nitrates/PH
Urine MC & S
Blood test-
FBC (normal)
Urine analysis and urine Dip
U and E's (creatine elevated)
Calcium 
CRP -  used to assess for infection
LFT
Renal function test - AKI 
Amylase (rule out pancreatitis)
Bone profile (loss in calcium)
Uric acid ( urate)
Pregnancy test (ectopic pregnancy)

Diagnostic

X ray

CT KUB (kidneys-ureters-bladder) Non contrast as patient may be nephrotoxic - first line gold standard

If CTKUB is positive - perform KUB to look at stone postion

Ultrasound for those who cant use CTKUB (pregnant women, children, adolescence)

29
Q

Which stones can not be detected on X ray?

A

uric acid, indinavir-induced, cystine, matrix

30
Q

Which drugs can lead promote calcium stone formation?(9) Which if these causes the formation of urate stones and calcium stones

A

Saltcat - G
S - Salicylate
A- Acetozolamide (carbonic anhydrase inhibitor used in glaucoma and epilepsy. Also a good diuretic which causes excretion of potassium and biocarbonate (carbonic anhydrase catalysis conversion of CO2 to biocarbonate) - used in metabolic acidosis )
L - Loop diuretics (Inhibits sodium/potassium/chloride transporter in the loop of Henle)
T- Thiazides (Inhibits reabsorption of sodium and chloride, inhibits sodium reabsorption and increases fluid excretion)

C - Vitamin C and D
A- Antacids
T- Theophylline (phosphodiesterase inhibiting used for COPD and asthma)
G- Glucocorticoids

U rate = Salicylate and Thiazides

31
Q

What are some potential differential diagnosis for renal colic?

A

Abdominal -

  • leaking AAA, bowel colic (goes and comes completely with uteric colic pain is in background)
  • Ectopic pregnancy
  • Pancreatitis

Chest and heart-
Pneumonia
MI

Urinary -

  • pyelonephritis
  • Bleeding tumours (renal call carcinoma)
  • Cystitis
32
Q

What about a kidney stones does the CTKUB assess?

A

Position, Size, Hardness

33
Q

Which imaging test is used to assess kidney stones in women who are in their second or third trimester of pregnancy?

A

MRI

Poor for stones

34
Q

Which factors dictate the management of renal colic?

A

Size and location of the renal stone
A stone <4mmm has a 80% chance of passing spontaneously

  • > 8mm less likely to pass alone
35
Q

How is renal colic medically managed?

A

Monitor and expulsion

Analgesia
NSAIDS- usually in acute situations but may effect renal function. Help reduce uretal spasm especially when given by the rectal route
Opiates - sometimes

Antiemetics
ondansetron or cyclizine

Hydration
Iv if patient is vomiting but this wont push out the stone

Medical expulsive therapy - Tamsulosin - relaxes lower ureter and increases stone passage

Stone removal

36
Q

In which kinds of patients should NSAIDS not be used and what should patients be offered instead?

A

AKI

History of Peptic ulcer or Gastritis

Give paracetamol

37
Q

How is renal colic surgically managed

A

Shockwave lithotripsy- shock wave is used to break down stone. Used in stones under 20mm

Ureteroscopy - energy devices e.g. lasers used to break down stone. Used in stones 10-20mm
Can be flexible or semi ridged

Percutaneous nephrolithotomy - nephroscope is passed into the collecting system and used to break up stones. used in stones >20mm
Used in other stones when other measures have failed

38
Q

What are the metabolic tests done for those with renal stones? (5)

A
2 x 24h urine collection: test for 
Calcium,	
Oxalate,	
Urate,	
Volume,	
Sodium		
 Citrate	

Spot Nitroprusside test for Cysteine

Stone analysis

Blood tests - calcium, urate, bicarbonate, U and E’s

Parathyroid hormone test

39
Q

What are the indications for a metabolic test?

A
  • Multiple stones attacks
  • Bilateral stone disease
  • Solitary kidney (increased risk)
  • Urate, cysteine, calcium stones
40
Q

How are renal stones be prevented non medically?

A
Increase fluid intake - >2l a day
Reduce sodium intake 
Increase potassium intake 
restrict high oxalate foods
reduce fatty acids 
take calcium with high protein meals 
Reduce animal protein intake 
Not more than 1000% - one tablet of vitamin C daily
41
Q

Which drugs are used to treat/prevent renal stones?

A

Calcium oxalate stones-
Thiazides- bendroflumethazide (hypercalciuria stones to reduce calcium excretion)

Renal tubular acidosis
Potassium citrate (alkalines urine)

Sodium bicarbonate - alkalines urine

Cystein stones - Tiopronin

Struvite - Antibiotics for UTI

Urate stones-
Allopurinol

Cystein stones- Penicillamine & Thiola for Cysteinuria

42
Q

Which tests are used to monitor the treatment of renal stones?

A

24h urine (assess for volume (patient drinking enough), sodium and to ensure specific therapy is working - citrate, oxalate, restriction)

Spot urine for Na/K as an alternative,

Blood urate in users of allopurinol

43
Q

Give examples of the type of metabolic conditions being assessed in the metabolic test? - you can only mention 2 here

A

hyperparathyiodsm and distal renal tubular acidosis

44
Q

How are patients with renal stones followed up?

A

50% chance another stone will present in 10 years if no dietary changes are made

Consider a 6 monthly KUB to follow unknown or asymptomatic stones

45
Q

Which factors effect the formation of calcium oxalate crystals?

A

High oxalate concentration in urine
Loss of stone inhibitors
High urinary PH (alkaline)

46
Q

What are the non- modifiable risk factors for renal stone development?

A
  • Male
  • Infection
  • Crohns disease
  • Family history
  • Metabolic disorder
  • anatomic abnormalities
  • primary renal diseases (polycystic kidneys, medullary sponge kidneys, renal tubular acidosis)
47
Q

What are the modifiable risk factors for renal stone development?

A
  • Dehydration - concentrated urine
  • Increased BMI
  • High salt diet
  • High meat diet
48
Q

Which complications of renal stones causes lasting damage?

A

Infection

Obstruction leading to hydro nephrosis

49
Q

Which metabolic conditions lead to kidney stone formation and how? What are the potential causes of these conditions

A

Hypercalcaemia
If the GFR is low then it can cause hypercalciuria. Causes include hyperparathyroidism, vitamin D ingestion and sarcoidosis

Hypercalciuria (high calcium in urine) - 24h urine calcium excretion of >7.5mmol for men and 6.5mmol form women.
Causes, Hypercalcaemia, increased calcium ingestion, idiopathic (enhanced gut uptake and urine excretion)

Hyperoxaluria - increase oxalate in urine. For oxalate to make stones with.
Causes -
Increased ingestion of food with oxalate in them
Dietary calcium restriction which causes increased absorption of oxalate
GI diseases like Crohns -increased absorption of oxalate from colon

Cystinuria
causes - polycystic kidney disease, medullary sponge kidney, renal tubular acidosis

50
Q

How do infections such as a urinary tract infection lead to renal stone formation?

A

UTI causes the formation of mixed infective stones (struvite + calcium)

These stones are large forming staghorn calculus,

Cause of UTI in this case is Proteus mirabilis