Nephrology Flashcards
What is the RAAS system
Renin - angiotensin - aldosterone - system
what triggers the RAAS system
Blood pressure decreases. Sympathetic nervous system is stimulated (constrictive), MDC’s sense drop in Na+
Describe the RAAS
Trigger sets of release of renin from the juxta-glomerular cells
Renin mixes with angiotensinogen to make ACE 1
AC1 mixes with ACE converting enzyme to male ACE 2
ACE 2 acts on adrenal medulla to release aldosterone from the zona glomerulous cells
ACE 2 also increase sympathetic activity and causes constriction of the mouth muscle cells
ACE 2 acts on pituitary and increases ADH secretion = increased H20 reabsorption back into the body meaning less fluid is released as urine
What 3 actions does ACE 2 have on the body?
- Signal pituitary to release and increase ADHormone, causes increase of fluid reabsopriton back into the body = less urine
- Stimulates sympathetic nervous system and restricts blood vessels
- Signals adrenal gland to release aldosterone
Where is aldosterone released from?
Adrenal cortex (outside of the kidney)
What is the function of aldosterone
Acts on the kidneys and colon:
- increase the amount of sodium and chloride reabsorbed into the blood stream (therefore more water)
- increase the amount of potassium excreted into the urine
What are the 3 subgroups of AKI
Pre renal
Intra renal
Post renal
What does AKI mean
Acute Kidney Injury
What is often associated as the cause of pre renal AKI
Heart problems
examples of pre-renal AKI causes (6)
- Hypovolemia (burns, vomiting, diarrhoea, dehydration)
- Extreme blood loss (trauma)
- Renal artery stenosis
- V-fib = low cardiac output = low perfusion
- Cardiogenic shock!
- Occlusion
What is often associated with intra-renal AKI
Renal injury
What are some causes of intra-renal AKI?
- Acute Tubular Necrosis
- Acute interstitial nephritis
- Glomerulonephritis
- Rhabdomyolysis
- Tumour lysis syndrome
What is often associated with post-renal AKI
Ureters, Bladder and urethra
What are common causes of post-renal AKI?
Ureter = stones, fibrosis and tumour/mass pressing to occlude
Bladder = transitional zone malignancy, blocked catheter
Urethral = tumour, stones, BPH
What is measured to diagnose AKI
Creatinine and urine output
What is classified as stage 1 AKI?
Creatinine increased 26 micromol OR 1.5-1.99x baseline
OR
Urine output <0.5 for more than 6 hours
What is classified as stage 2 AKI
Creatinine of 2-2.99x baseline
OR
Urine <0.5 for more than 12 hours
What classification indicates stage 3 AKI?
Creatinine 3x baseline
OR
Urine output <0.3 for more than 24 hours OR anuria for 12 hours
What is acute tubular necrosis
- Cause of intra-renal AKI
- ischaemia/death of epithelial cells of the renal tubule
- indicated by muddy brown casts through a microscope
- most common cause of intra-renal AKI
What are types of Acute Tubular necrosis
Ischaemic and Neprotoxic
What is ischameic acute tubular necrosis
Poor blood flow = cell death due to hypoperfusion
What is nephrotoxic ATN
Death of epithelial cells of the renal tubules due to drugs such as:
- diuretics
- Aminoglycosides (vancomycin and gentomycin)
- metformin
- NSAIDs
- IV contrast and chemo (cisplatin)
What is AIN
Acute interstitial necrosis
What is ATN
Acute tubular necrosis
What causes AIN (3 categories)
- Drugs usually = diuretics(furosemide), antibiotics (penicillin), allopurinol (gout), NSAIDs
- SLE, Sjorgrens and sarcoidosis (connective tissue disease)
- Infection
What are signs of AIN
White cell casts under microscope
Pyuria (puss urine)
Triad - fever, rash and eosinophils on FBC
What is renal artery stenosis
Cause of pre-renal AKI
What are renal stones
Calcifications that form in renal pelvis and travel down the ureters
- obstruct the vesicles-uterine junction
- can cause post-renal AKI
- can cause obstructive pyelonephritis
What is the most common form of renal stone
Calcium oxalate
What are common renal stones/ (5)
- Calcium oxalate
- Calcium phosphate
- Uric acid stones (due to gout)
- Cystine stones
- Xanthine stones
- Struvite stones = staghorn
What renal stones are caused by infection
Struvite
What renal stones are caused by gout?
Uric acid stones
what renal stones are radio lucent
Uric acid stones and xanthine stones
How to treat renal stones in emergency
If infection/emergency situations = treat as emergency and use analgesia (IV diclofenac + paracetamol)
How to treat a <5mm renal stone
Watch and wait
How to treat a 5-10mm renal stone
Shockwave lithotripsy
How to treat a 10-20 mm renal stone
Shockwave lithotripsy + uretoscopy
How to treat a >20mm renal stone or Staghorn
Nephrolithotomy - consider URS if PCNL is not an option
When is pre-stenting used in shockwave therapy
Staghorn calcifications
What is used to diagnose renal stones
Non-contrast CT
How to treat pre-renal AKI?
250-500ml fluid and STOP any DAMN dugs
What other drugs need to be stopped in AKI
Lithium & Digoxin
What can AKI lead to?
Hyperkalaemia
How do we treat hyperkalameia
- IV calcium gluconate
- Insulin/dextrose infusions to pull potassium into cells out of blood. OR neb salbutamol for same reason
- Calcium resonium (remove all potassium)
- Sodium bicarbonate pulls potassium into cells and out of blood
- Haemodialysis
What is defined as chronic kidney disease
Rapid decline in function within 3 months
What causes chronic kidney disease?
- High blood sugars (causes scaring of the kidneys as sugar passes through) = increased creatinine
- Hypertension (high blood pressure = scarring)
- Medications/drugs
- Glomerulonephritis
- PCKD
What is ADPKD
Autosomal Dominant Polycystic kidney disease
Signs and symptoms of CKD (6)
- pallor
-foamy urine from protein leakage - nausea
- pruritis
- HTN
- peripheral neuropathy
What are 3 measurements to diagnose CKD
- Haematuria
- eGFR
- ACR
What does ACR measure in CKD
Proteinuria
What does eGFR measure in CKD
Creatinine, age and gender - kidney function/filtration power
what does haematuria measure in CKD
Infection, malignancy, glomerular nephritis, ADPKD, stones
What is key when diagnosing CKD
Need consistent results 3 months apart
What is the eGFR classification of stage 1 kidney disease
Stage 1 = >90 eGFR
What is the eGFR classification of stage 2 CKD
Stage 2 eGFR 60-89 with some signs of kidney damage ( not just egfr signs need to be there and kidney tests need to be abnormal)
what is the eGFR classification for stage 3a kidney disease
Stage 3a = 45-59, moderate reduction in kidney function
What eGFR classification is correct for stage 3b CKD
Stage 3b - 30-44 moderate reduction
what eGFR classification signifies stage 4 CKD
Stage 4 = 15-29 severe reduction
What eGFR classification is stage 5 CKD
<15 = established kidney failure, dialysis or transplant may be needed
What ACR classification indicates stage 1 CKD
<3mg
What ACR signifies stage 2 CKD
3-30mg
What ACR signifies stage 3 CKD
30mg+
what should be started if ACR stage 3 CKD
ACE inhibitors or ARB if meeting the criteria and statins also recommended
What is accelerated progression
Sustained decline within one year of either 25% or 15ml
What zone is prostate cancer primarily developed from
Peripheral zone
What are 4 signs of prostate cancer
Urinary changes
Incomplete voiding
Nocturia
ED in some cases
What are red flags for prostate cancer
- blood in urine
- blood in sperm
- weight loss
- night sweats
- back pain (mets)
What can also be caused by prostate cancer
Acute hypercalcaemia due to bone degradation from tumours
What are the 4 developments of prostate cancer
Stone (stones)
Bone (joint/muscle pain)
Groan (loin to groin pain)
Psychiatric moan (depression)
Can prostate cancer casue back pain?
Yes as can spread to BREAST, BUNGS, BOSTATE, BONE, BIDNEY
What criteria is used to assess prostate cancer severity??
Gleason criteria
6 =low grade
7 = middle
9,9,10 = high
How to treat localised prostate cancer (T1/2)
- Conservatively (active monitoring/watch and wait)
- Radical prostatectomy
- Radiotherapy
How to treat localised advanced prostate cancer (T3/4)
HRT
Radical prostatectomy
Radiotherapy
How to treat metastatic prostate cancer
Anti-androgen therapy (GnRH agonist)
Chemo with docetaxel
What chemo is used in mets stage prostate cancer
Docetaxel
What are the red flags for renal cancer
Hameaturia
Loin pain
Abdo mass
Pyrexia
Cannon ball mets
Left sided varicocele (bag of worms)
What is the most common form of renal cell carcinoma
Clear cell
What area does bladder cancer stem from predominantly
Transitional cell
What key risk factor contributes towards. Bladder cancer
Smoking
What is a main issue of hyperkalaemia
Cardiac arrhythmia risk
What is classified as raised potassium
> 4.5 really but 5.4 + = mild
What is seen on ECG if hyperkalameic
Tall T waves no P waves broad QRS prolonged PR
What is Rhabdomyolysis
Break down of muscle cells releasing chemicals into blood
4 chemicals that release into the blood
K+, PO4-, myoglobin and CK
What chemical from Rhabdomyolysis can cause AKi
Myoglobin
5 causes of rhabdomyolysis
- Crush injuries
- Strenuous exercises
- Seizures
- Statins
- Prolonged immboility
What urine changes occur in rhabdomyolysis
Red/brown
What are the main 2 types of glomerulonephritis
Nephrotic and nephritic
What is glomerulonephritis
Inflammation of the glomerulous in the kidney
What are the 3 signs of nephrotic syndrome
Proteinuria
Peripheral oedema
Hypercholesterolameia
Low serum albumin
What are 4 symptoms of nephritic syndrome
- Hameaturia
- Oliguria
- Proteinuria
- Fluid retention
What is the key nephrotic syndrome in children
Minimal change disease
