Renal Flashcards
What is glomerulonephritis?
Immune mediated disease of the kidneys affecting the glomeruli with secondary tubo-interstitial damage
What mediates glomerulonephritis?
Antibody mediated - T cells, inflammatory cells, mediators, complement
What is the commonest cause of end stage kidney disease?
Diabetes
How does nephrotic syndrome present?
Proteinuria, oedema, hypoalbulinaemia, lipiduria
NON-PROLIFERATIVE
How does nephritic syndrome present?
Haematuria, hypertension, oedema, renal failure
PROLIFERATIVE
How is glomerulonephritis diagnosed?
Clinical presentation
Bloods
Urinalysis, microscopy, urine protein
Kidney biopsy
What are some causes of nephrotic syndrome?
Minimal change nephropathy
Focal segmental glomerulonephritis
Membranous glomerulonephritis
Whats the commonest cause of nephrotic syndrome in kids?
Minimal change nephropathy
What is the commonest cause of nephrotic syndrome in adults?
Focal segmental glomerulonephritis
‘Foot process fusion on EM’
Minimal change nephropathy
How do you treat minimal change nephropathy?
Steroids - should go into complete remission
Does minimal change nephropathy progress to renal failure?
No
What can cause focal segmental glomerulonephritis in adults?
Can be primary or secondary to HIV, heroin use and obesity
Does focal segmental glomerulonephritis progress to renal failure?
Yes - 50% have end stage kidney disease in 10 years
‘Focal segmental glomerulonephritis on LM’
Focal segmental glomerulonephritis
How is focal segmental glomerulonephritis treated?
Steroids
What causes membranous glomerulonephritis?
Can be primary or secondary to SLE, infection, malignancy, rheumatoid drugs (gold/penicillamine)
Can membranous glomerulonephritis progress to renal failure?
Yes
‘Thickened basement membrane on silver stain’
Membranous glomerulonephritis
How is membranous glomerulonephritis treated?
Steroids, alkylysing agents, monoclonal antibodies
What are causes of nephritic syndrome?
IgA nephropathy
Rapidly progressive glomerulonephritis
What is the commonest glomerulonephritis worldwide?
IgA nephropathy
‘Macroscopic haematuria 1-2 days following infection’
IgA nephropathy
‘Mesangial IgA proliferation’
IgA nephropathy
What condition does IgA nephropathy have some overlap with?
Henoch-Schonlein Purpura
How is IgA nephropathy treated?
Blood pressure control if needed
What is rapidly progressive glomerulonephritis?
A treatable cause of acute kidney failure that rapidly progresses over days to weeks
What are some ANCA +ve causes of rapidly progressive glomerulonephritis?
Vasculitis, Wegners, Churg-Strauss
What are some ANCA -ve causes of rapidly progressive glomerulonephritis?
Goodpastures, Henoch-Schonlein Purpura, SLE
What other organ does Goodpastures disease affect?
Lungs - haemoptysis, cough, SOB
What antibody is seen in Goodpastures?
Anti-GBM
‘Glomerular cresents seen’
Rapidly progressive glomerulonephritis
How is rapidly progressive glomerulonephritis treated?
Strong immunosuppressants +/- dialysis
What glomerulonephritis’ will give a mixed nephrotic and nephritic picture?
Membranoproliferative
Post-infective
What causes membranoproliferative GN?
Cryoglobulinaemia, HepC
‘Subendothelial IgG deposits’
Membranoproliferative GN
‘Tram track appearance of basement membrane’
Membranoproliferative GN
How is membranoproliferative GN treated?
Steroids
‘A child has a sore throat. 7-14 days later he has haematuria’
Post infective/Diffuse Proliferative GN
‘Coca cola urine’
Post infective/diffuse proliferative GN
‘Proliferation of mesangial cells, neutrophils and monocytes’
Post infective/diffuse proliferative GN
What is the criteria for AKI?
Rise of serum creatinine to >26 in 48hrs OR
Rise of serum creatinine to >50% of last 7 days OR
Fall in urine output to <0.5ml/kg/hr for more than 6hrs
What are pre-renal causes of AKI?
Lack of blood supply to kidneys - hypovolaemia, hypotension, drugs (NSAIDs, COX-2, ACEis, ARBs)
What are renal causes of AKI?
Vasculitis, IV contrast, toxins, glomerulonephritis, acute intersitital nephritis, rhabdomyolysis
What are post-renal causes of AKI?
Obstruction of urine outflow causing backpressure (e.g. stones, BPH, strictures, tumours)
What are risk factors for developing AKI?
CKD, Age over 65, diabetes, heart failure, liver failure, history of AKI, nephrotoxins
How do you prevent AKI?
Minimise risk factors
What are some signs and symptoms of AKI?
Can be asymptomatic
Reduced urine output, pulmonary and peripheral oedema, arrythmias, uraemic features (pericarditis, encephalopathy)
What investigations are important in AKI?
Bloods - FBC, U&Es, Clotting
Urinalysis - check for haemoproteinuria
Renal USS - within 24hrs to check for cause
What management is important in pre-renal AKI?
Fluids - 0.9% sodium chloride bolus then infusion
How should fluid status be assessed?
JVP, HR, BP, cap refil, urine output
What is a complication of untreated pre-renal AKI?
Acute tubular necrosis
What is acute tubular necrosis?
Death of renal tubular epithelial cells
‘Muddy brown casts’
Acute tubular necrosis
What is an important investigation to carry out in intrinsic AKI?
Renal biopsy - assess for glomerulonephritis
What is the specific management of post-renal AKI?
Catheter/nephrostomy/stent
What medications should be stopped in AKI?
NSAIDs, aminoglycosides, ACEis, ARBs, diuretics
What metabolic complication may occur in AKI?
Hyperkalaemia
What ECG changes does hyperkalaemia cause?
Tall tented T waves
How is hyperkalaemia treated?
Calcium gluconate 10mls of 10% IV
Nebulised salbutamol
Insulin/Dextrose continuous infusion
Calcium resonium/dialysis
What may be considered in AKI if medical management does not get an adequate response?
Haemodialysis
What are complications of AKI?
Increased length of hospital stay
Increased mortality and morbidity
Increased risk of CKD
What is CKD?
Reduced eGFR and/or evidence of kidney damage that is chronic
What equation is used to work out eGFR?
MDRD4
What variables does the MDRD4 counteract?
Creatinine, race, sex, age
What is classified as stage I CKD?
eGFR >90ml/min AND evidence of kidney damage
What is classified as stage II CKD?
eGFR 60-90ml/min AND evidence of kidney damage
What is classified as stage IIIA CKD?
eGFR 45-59ml/min
What is classified as stage IIIB CKD?
eGFR 30-44ml/min
What is classified as stage IV CKD?
eGFR 15-29 ml/min
What is classified as stage V CKD?
eGFR <15ml/min
What are causes of CKD?
Diabetes, hypertension, vascular disease, glomerulonephritis, PCKD, unknown
What are symptoms of CKD?
Usually non-specific - tiredness, poor appetite, itch, sleep disturbance
Which patients are more likely to progress in CKD?
Patients with proteinuria, younger patients
How is cardiovascular risk reduced in patients with CKD?
Stop smoking, lose weight, healthy diet
Statin and Aspirin
What management can slow the progression of CKD?
By decreasing proteinuria by controlling BP
Use ACEis and ARBs
What is the target blood pressure in CKD?
140/90 or 130/80 in diabetics
What kind of anaemia do patients with CKD get?
Normocytic normochromic anaemia
Why do patients with CKD become anaemia?
Decrease in erythropoetin
How is anaemia treated in CKD?
Correct any deficiencies
Give erythropoeitin injections
How should bones be protected in CKD?
Phosphate binders, calcium and vitamin D
How should oedema be treated in CKD?
Loop diuretics
When is dialysis considered in CKD?
End stage kidney disease - when eGFR <20
What must be formed in order to carry out haemodialysis?
Arteriovenous fistula
Why is an arteriovenous fistula needed?
Means there is not continuous cannulation of small veins that may eventually collapse
Allows for faster blood flow
How long after formation of an AV fistula will it be functional?
6 weeks
What is dialysed out of a patient?
Urea, creatinine, potassium, toxins
What is dialysed into a patient?
Water, sodium, potassium, bicarbonate, glucose
What is the minimum amount of time dialysis should be done?
At least 4 hours 3 times a week
What restrictions are put on a patient on haemodialysis?
1L fluid per day, low salt diet, low potassium diet, low phosphate diet
How does peritoneal dialysis work?
Solute removed by diffusion across the peritoneal membrane
What are some complications of peritoneal dialysis?
Infection, membrane failure, hernias
When can a patient with CKD be put on the transplant list?
When they are within 6 months of starting dialysis
What can cause an increase in urea?
Dehydration, GI bleed, increased protein breakdown (infection, malignancy), drugs, high protein diet
What may cause a low urea?
Malnutrition, liver disease, pregnancy
What does a rise in both urea and creatinine suggest?
Renal dysfunction
What is the likely cause of haematuria in a patient just back from a holiday to India/Malawi?
Schistosomiasis
What are some renal features of autosomal dominant kidney disease?
Hypertension, recurrent UTI, abdominal pain, renal stones, haematuria, renal stones
What are some extra renal features of ADPKD?
Liver cysts, berry aneurysms
What is Alports Syndrome?
Genetic syndrome caused by a defect in type IV collagen
How is Alports syndrome inherited?
X-linked dominant
What symptoms and signs do you get in Alports syndrome?
Microscopic haematuria Progressive renal failure Bilateral sensorineural deafnes Lenticonus - anterior lens dislocation Retinitis Pigmentosa
What are ‘eosinophilic casts’ in the urine found in?
Chronic pyelonephritis
In pre-renal AKI, what is the urinary osmolality and urinary sodium like?
Urinary osmolality HIGH
Urinary sodium LOW
In renal AKI, what is the urinary osmolality and urinary sodium like?
Urinary osmolality LOW
Urinary sodium HIGH
What is the best investigation for hydronephrosis?
Ultrasound