Corrections - Renal Flashcards
What are the causes of an Addisonian crisis?
1) sepsis or surgery causing an acute exacerbation of chronic insufficiency (Addison’s, Hypopituitarism)
2) adrenal haemorrhage e.g. Waterhouse-Friderichsen syndrome (fulminant meningococcemia)
3) steroid withdrawal
What blood tests are seen in an Addisonian crisis?
Low sodium
High potassium
Low glucose
What causes low sodium in Addisonian crisis?
Aldosterone deficiency (leading to renal sodium loss)
What causes high K+ in Addisonian crisis?
A deficiency of aldosterone will result in potassium retention, through its inability to excrete potassium in the urine.
What causes low glucose in Addisonian crisis?
Lack of cortisol –> decreased glucose production by the liver and decreased glucose uptake by peripheral tissues, leading to hypoglycemia.
Management of Addisonian crisis?
1) Hydrocortisone 100mg IM or IV
2) 1 litre normal saline infused over 30-60 mins or with dextrose if hypoglycaemic
3) Continue hydrocortisone 6 hourly until the patient is stable.
4) Oral replacement may begin after 24 hours and be reduced to maintenance over 3-4 days
What is a hallmark in the diagnosis of prerenal uraemia?
Normal urine osmolarity with a low urine sodium (<20).
What is one of the most common cuses of prerenal uraemia in elderly patients?
Dehydration
Give 5 causes of pruritus
1) liver disease
2) iron deficiency anaemia
3) polycythaemia
4) CKD
5) lymphoma
When does pruritus in polycythaemia usually occur?
After warm bath
What is acute interstitial nephritis (AIN)?
An immunologically mediated renal disorder characterised by inflammation of the renal interstitium, predominantly affecting tubules and interstitial spaces.
What is the most common cause of AIN?
1) Drugs: particularly Abx
- penicillin
- rifampicin
- NSAIDs
- allopurinol
- furosemide
2) Systemic disease:
- SLE
- sarcoidosis
- Sjogren’s syndrome
3) Infection:
- Hanta virus
- staphylococci
Clinical features of AIN?
- fever, rash & arthralgia
- eosinophilia (causes allergic picture)
- mild renal impairment
- HTN
What may urinalysis show in AIN?
- white cell casts
- sterile pyuria
Give some indications for dialysis in AKI
When a patient is not responding to medical treatment of complications:
1) hyperkalaemia
2) pulmonary oedema
3) acidosis
4) uraemia (e.g. pericarditis, encephalopathy)
Which NSAID is generally safe to continue in AKI?
Aspirin
What is required for a diagnosis of CKD stage 1?
eGFR >90 ml/min BUT has to have some signs of kidney damage on other tests e.g. proteinuria, haematuria electrolyte abnormalities, raised urea/creatinine
What medication should all patients with CKD be started on?
Statins: for the primary or secondary prevention of cardiovascular disease (CVD).
What are complications of TURP?
T - Turp syndrome
U - Urethral stricture/UTI
R - Retrograde ejaculation
P - Perforation of the prostate
What is TURP syndrome?
Occurs when irrigation fluid enters the systemic circulation.
What triad of features is seen in TURP syndrome?
1) hyponatraemia: dilutional
2) fluid overload
3) glycine toxicity
Management of TURP syndrome?
1) fluid restrictoin
2) treatment of the complications associated with the hyponatraemia.
How does TURP syndrome affect sodium?
Hyponatraemia
What 2 conditions are associated with seborrhoeic dermatitis?
1) HIV
2) Parkinson’s disease
What is a non-calcium based phosphate binder that treats hyperphosphataemia in patients with CKD mineral bone disease?
Sevelamer
Urine sodium in pre-renal uraemia vs ATN?
ATN: >40 mmol/L
Pre-renal uraemia: <20 mmol/L
Give 3 factors that can invalidate an eGFR result?
1) eating red meat the evening before a blood test (due to creatinine in the meat)
2) pregnancy
3) muscle mass (e.g. amputees, body-builders)
Management of urine output of < 0.5ml/kg/hr postoperatively?
Consider STAT fluid bolus of 500ml 0.9% saline (if there are no contraindications or signs of haemorrhage etc)
What urea & creatinine results indicate dehydration?
urea is proportionally higher than the rise in creatinine
1st line for reducing phosphate levels in CKD (to prevent further complications of CKD-mineral bone disease)?
Recommend low phopshate diet
2nd line for reducing phosphate levels in CKD (to prevent further complications of CKD-mineral bone disease) i.e. if diet hasn’t worked?
Prescribe phosphate binders
When should patients with CKD be started on an ACEi?
If they have an ACR >30 mg/mmol
What location of back pain is a red flag?
Thoracic back pain
Why is thoracic back pain a red flag?
Thoracic back pain may indicate the possibility of spinal cord compression, spinal osteomyelitis, or epidural abscess.
What is required for a diagnosis of CKD stage 2?
eGFR 60-90 ml/min AND signs of kidney damage (i.e. if kidney tests* are normal, there is no CKD)
What rise in creatinine is diagnostic of an AKI?
Rise >26 umol/L in 48 hours
OR
Rise >50% in 7 days
What is the most common cause of compartment syndrome?
Tibial fracture
How is compartment syndrome a risk factor for an AKI?
Increased pressure in the fascial compartment may lead to muscle breakdown and myoglobin released into the bloodstream (rhabdomyolysis).
Deposition of myoglobin in the renal tubules results in AKI, with myoglobinuria causing a dark, brown coloured urine, which dips positively for blood.
What should raise suspicion for compartment syndrome?
excessive use of breakthrough analgesia for pain
What indicates AKI stage 1?
Increase in creatinine to 1.5 - 1.9x baseline
OR
Increase in creatinine by >/= 26.5 umol/l
OR
Reduction in urine output to <0.5 mL/kg/hour for >/= 6 hours
What indicates AKI stage 2?
Increase in creatinine to 2.0 - 2.9x baseline
OR
Reduction in urine output to <0.5 mL/kg/hour for ≥12 hours
Typical blood test findings in osteomalacia?
Low serum calcium
Low serum phosphate
Raised ALP
Raised PTH
What is osteomalacia typically caused by?
Low vit D
Is warfarin safe to continue is AKI?
Yes - it is also generally the anticoagulant of choice in patients with marked CKD
How do the kidneys appear on US in the early stages of diabetic nephropathy?
Enlarged kidneys (in contrast to most other causes of CKD)
In patients with diabetes and CKD, what is the target BP?
<130/80
1st line antihypertensive in patients with CKD and diabetes?
ACEi
Urine sodium in pre-renal uraemia (‘azotemia’) vs ATN
Pre-renal uraemia: <20 mmol/L
ATN: >40 mmol/L
How can urea/creatinine levels indicate dehydration?
urea is proportionally higher than the rise in creatinine
When is calcium acetate indicated in CKD?
Calcium acetate is a calcium-based binder that is used to manage hyperphosphataemia in CKD.
Side effects of calcium-based binders such as calcium acetate (taken in CKD)?
Hypercalcaemia & vascular calcification
Transjugular Intrahepatic Portosystemic Shunt (TIPSS) can be used in oesophageal varices if other methods (e.g. band ligation) are not successful.
What is a common complication of TIPSS?
Exacerbation of hepatic encephalopathy
