Renal Flashcards
(134 cards)
When can an official diagnosis of an AKI be made ?
- Rise in serum creatinine of 26 micromol/litre or greater within 48 hours
- 50% or greater rise in serum creatinine known or presumed to have occurred within the past 7 days
- Fall in urine output to less than 0.5 ml/kg/hour for more than 6 hours in adults and more than
What are the pre renal causes of an AKI ?
- Hypovolaemia secondary to D&V
- HF
- Renal artery stenosis
What are the intrinsic causes of AKI ?
- Glomerulonephritis
- Acute tubular necrosis (ATN)
- Acute interstitial nephritis (AIN)
- Rhabdomyolysis
- Tumour lysis syndrome
- HUS
What are the postrenal causes of AKI?
- Kidney stone in ureter or bladder
- BPH
- External compression of the ureter
what are the signs of an AKI?
- Reduced urine output
- Pulmonary and peripheral oedema
- Rise in K+ = arrhythmias
- Rise in urea / creatinine
- Features of uraemia (pericarditis / encephalopathy)
RF for an AKI
- CKD
- Other organ failure/chronic disease e.g. heart failure, liver disease, diabetes mellitus
- History of AKI
- Use of drugs with nephrotoxic potential (e.g. NSAIDs, aminoglycosides, ACEI/ARBs within the past week
- Use of iodinated contrast agents within the past week
- AGge >=65 years
What is acute tubular necrosis and what can it be caused by ?
- Most common cause of AKI
- Necrosis of renal tubular epithelial cells
- Caused by : ischaemia due to hypoperfusion or nephrotoxins
What will be seen on urinalysis in acute tubular necrosis ?
Muddy brown casts
What can cause acute interstitial nephritis ?
- Drugs : acute interstitial nephritis accounts for 25% of drug-induced AKI
- Systemic disease : SLE, sarcoidosis and Sjogrens
- Infection : Hanta virus, staphylococci
What drugs can cause acute interstitial nephritis
- Penicillin
- Rifampicin
- NSAIDs
- Allopurinol
- Furosemide
what will be seen on urinalysis in acute interstitial nephritis
- Sterile pyuria
- White cell casts
4 features of acute interstitial nephritis
- Fever, rash, arthralgia
- Eosinophilia
- Mild renal impairment
- HTN
what medications should be stopped in an AKI
- NSAIDs (except if aspirin at cardiac dose e.g. 75mg od)
- Aminoglycosides
- ACE inhibitors
- Angiotensin II receptor antagonists
- Diuretics
what is involved in the management of AKI
- Careful fluid balance
- Stop any nephrotoxic medications
- Correction of hyperkalaemia if present
Give 5 causes of CKD
- Diabetes
- HTN
- Polycystic kidney disease
- Chronic glomerulonephritis
- Chronic pyelonephritis
what investigations are used to assess CKD
- eGFR
- Proteinuria quantified with urine albumin:creatinine ratio
- Haematuria
- Renal USS
How does nephrotic syndrome present ?
- Oedema
- Possible frothy urine due to the high protein content
How is CKD classified based on eGFR ?
- 1 : Greater than 90 ml/min, with some sign of kidney damage on other tests
- 2 : 60-90 ml/min with some sign of kidney damage
- 3a : 45-59 ml/min, a moderate reduction in kidney function.
- 3b : 30-44 ml/min, a moderate reduction in kidney function
- 4 : 15-29 ml/min, a severe reduction in kidney function
- 5 : Less than 15 ml/min, established kidney failure - dialysis or a kidney transplant may be needed
How is CKD classified based on albumin:creatinine ration ?
- A1 : <3mg/mmol
- A2 : 3-30 mg/mol
- A3 : >30mg/mol
what are the group of features seen in nephritic syndrome
-> Haematuria (blood in the urine), which can be microscopic (not visible) or macroscopic (visible)
-> Oliguria (significantly reduced urine output)
-> Proteinuria (protein in the urine), but less than 3g per 24 hours (higher protein suggests nephrotic syndrome)
-> Fluid retention
what is nephritis ?
Inflammation in the kidney
Primary causes of nephrotic syndrome
- Minimal change disease
- Focal segmental glomerulosclerosis (FSGS),
- Membranous nephropathy.
Most common type of inherited kidney disease
- AD
- PKD1 gene on chromosome 16 (85% of cases)
- PKD2 gene on chromosome 4 (15% of cases)
What is nephrotic syndrome ?
- The basement membrane of the glomerulus becomes highly permeable resulting in significant proteinuria