Genitourinary - AKI, Polycystic Kidney Disease, CKD Flashcards
Acute Kidney Injury (AKI) - what is it and what does it lead to?
It is a reduction in renal function following insult to the kidneys
Leads to failure to maintain fluid, electrolyte and acid-base homeostasis
AKI - what compound is measured to diagnose AKI?
Creatinine
AKI - what are the three NICE criterions for diagnosing AKI?
- Rise in creatinine of ≥ 26 micromol/L in 48 hours
- Rise in creatinine of ≥ 50% over 7 days
- Urine output of <0.5ml/kg/hour for > 6 hours
AKI - what are some risk factors that would predispose someone to an AKI?
Patient that is suffering from an acute illness or having a surgical operation
CKD HF DM Liver disease Older age
Nephrotoxic meds - NSAIDs and ACEi
AKI - what are the causes?
Pre-renal causes:
- Due to inadequate blood supply to kidneys
- Hypotension
- Renal artery stenosis
- Dehydration
Renal causes: 1. Tubular: Acute tubular necrosis - ischaemia Nephrotoxins - aminoglycosides, NSAIDs 2. Glomerular: Caused by antigen-antibody complexes depositing in the glomerular tissue Glomerulonephritis
Post-renal causes:
- Obstruction to outflow of urine from kidneys, causing back-pressure and reduced kidney function
- Kidney stones in ureter or bladder
- BPH
- Masses such as cancers
AKI - symptoms and signs?
Patients with early AKI may experience no symptoms
As renal failure progresses, may seen:
- Reduced urine output
- Pulmonary and peripheral oedema
- Arrhythmias - secondary to changes in K+ and acid base balance
AKI - what are the investigations?
U&Es
Urinalysis - to check for:
protein and blood - suggest acute nephritis
leucocytes and nitrites - suggest infection
glucose - suggests diabetes
Renal ultrasound - to look for obstruction if necessary
AKI - how do you prevent AKI?
Avoid nephrotoxic meds
Ensure adequate fluid input
AKI - treatment?
Fluid rehydration - IV fluids in pre-renal AKI
Stop nephrotoxic meds
Relieve obstruction
Polycystic Kidney Disease - what is it?
Genetic condition where kidneys develop multiple fluid-filled cysts, causing significant kidney impairment
Polycystic Kidney Disease - what is the type of genetic inheritance?
There is BOTH an autosomal dominant and recessive type
Dominant more common
Polycystic Kidney Disease - in ADPKD where do the mutations occur?
85% of cases - mutations in PKD1, chromosome 16
15% of cases - mutations in PKD2, chromosome 4
Polycystic Kidney Disease - what are the clinical features?
Abdo pain Haematuria HTN Recurrent UTIs Kidney stones CKD
Polycystic Kidney Disease - what are the extra-renal manifestations?
Liver Cysts (most common) - may cause hepatomegaly
Berry aneurysms
Cardaic valvular disease - mitral regurg
Splenic, pancreatic, ovarian, prostatic cysts
Polycystic Kidney Disease - autosomal recessive type:
1. Chromosome affected, and what does it encode?
- How does it often present?
- What are the clinical features?
- Chromosome 6, defect in gene that encodes protein fibrocystin, protein important for renal tubule development
- Often presents as oligohydraminos as the fetus does not produce enough urine
- Dialysis - first few days of life
Dysmorphic features - underdeveloped ear cartilage, low set ears, flat nasal bridge
End stage renal failure in childhood