Nephrology Flashcards
What is the average GFR in a neonate?
20-30ml/min
By what age does the GFR equal an adult?
2yrs
What are the 5 basic kidney functions?
- Waste handling
- Water handling
- Salt balance
- Acid base control
- Endocrine
What are parts of the glomerular filtration barrier?
Endothelial cell
Glomerular basement membrane (GBM)
Podocyte
Mesangial cells
What suggests glomerular injury?
Proteinuria
What is the underlying cause of: increasing haematuria and intravascular overload?
Nephritic syndrome
What is the underlying cause of: increasing proteinuria and intravascular depletion?
Nephrotic syndrome
If the epithelial cell (podocyte) is affected in acquired glomerulopathy what is the likely pathology?
Minimal Change Disease
If the basement membrane is affected in acquired glomerulopathy what is the likely pathology?
Post Infectious Glomerulonephritis (PIGN)
If the endothelial cell is affected in acquired glomerulopathy what is the likely pathology?
PIGN, Haemolytic uraemic syndrome (HUS)
If the mesangial cell is affected in acquired glomerulopathy what is the likely pathology?
HSP/IgA nephropathy
Which is common and which is rare out of acquired and congenital glomerulopathy?
Acquired - common
Congenital - rare
If the podocyte cytoskeleton integrity is affected in congenital glomerulopathy what is the likely pathology?
Congenital nephrotic syndrome
Mutations in which proteins can lead to congenital nephrotic syndrome?
Podocine
Nephrin
If the basement membrane proteins are affected in congenital glomerulopathy what is the likely pathology?
Alport syndrome
Thin basement membrane disease
If the endothelial/microvascular integrity is affected in congenital glomerulopathy where is the likely pathology?
Complement regulatory proteins (MPGN)
How can you check for proteinuria?
Dipstix
Protein Creatinine Ratio
24hr urine collection
What is the gold standard for checking proteinuria?
24hr urine collection
When is a dipstix usually abnormal?
> 3+
What does a dipstix do?
Measures concentration of protein
When is it best to measure protein creatinine ratio?
Early morning urine
When is the Protein Creatinine ratio in the nephrotic range?
> 250mg/mmol
What is the normal protein creatinine ratio?
Pr:CR ratio <20mg/mmol
What are common symptoms of nephrotic syndrome?
Nephrotic range proteinuria
Hypoalbuminaemia
Oedema
What is a typical presentation of nephrotic syndrome?
Swollen face (worse in mornings) Exam: pale, looked well, inflated weight, periorbital oedema, pitting oedema legs, ascites, small pleural effusions, frothy urine
What three things diagnose nephrotic syndrome?
Oedema
Proteinuria
Low albumin (bloods)
What is the most common cause of nephrotic syndrome in children?
Minimal change disease
What are typical features of nephrotic syndrome?
Normal BP
No frank haematuria
Normal renal function
Typically age 1-10
What are atypical features of nephrotic syndrome?
Suggestions of autoimmune disease
Abnormal renal function
Steroid resistance
What is the treatment for nephrotic syndrome if typical features?
Prednisolone 8wks
What are the typical side effects from high dose glucocorticoids that parents notice?
Behaviour
Mood lability
Sleep disturbance
What do doctors need to consider in terms of side effects from high dose glucocorticoids in children?
Infection risk
Hypertension
What percentage of children with nephrotic syndrome should react to steroids?
90%
What percentage of nephrotic syndrome in children relapse?
80%
What is an acquired nephrotic syndrome that can be steroid resistant?
Focal Segmental Glomerulosclerosis (FSGS)
What are congenital nephrotic syndromes that can be steroid resistant?
NPHS1 - nephrin
NPHS2 - podocin
If there is haematuria and associated proteinuria what would you assume?
Glomerular disease
What are some causes of haematuria?
Systemic: clotting disorder Renal: glomerulonephritis Tumour/malignancies Cysts UTI Stones Trauma Urethritis
If there is frank haematuria, is it more likely nephrotic or nephritic?
Nephritic
What is the usual cause of acute post-infectious glomerulonephritis?
Group A strep
How would you diagnose acute post-infectious glomerulonephritis?
Bacterial culture
Positive ASOT
Low C3 complement level normalises
What is the treatment for post-infectious glomerulonephritis?
Antibiotic
Support renal function
Diuretics for overload/hypertension
What is the outcome for post-infective glomerulonephritis usually?
Self-limiting
How would you make clinical diagnosis of Henoch Schonlein Purpura (IgA related vasculitis)?
Mandatory palpable purpura One of 4: - Abdo pain - Renal involvement - Arthritis or arthralgia - Biopsy: IgA deposition
What is the most common childhood vasculitis?
IgA vasculitis
When does IgA vasculitis usually occur?
1-3 post-trigger e.g. virus
How long does IgA vasculitis usually last?
4-6wks
What is the treatment for IgA vasculitis?
Symptomatic
Glucocorticoid therapy
Immunosuppression
What is the most common glomerulonephritis?
IgA nephropathy
How does IgA nephropathy present clinically?
Recurrent macroscopic haematuria
+/- chronic microscopic haematuria
Varying degrees of proteinuria
How is IgA nephropathy diagnosed?
Clinically
Confirmation renal biopsy
What biopsy is done in IgA nephropathy for confirmation?
Renal biopsy
What is the treatment for mild IgA nephropathy?
Proteinuria with ACEi
What is the treatment for moderate to severe IgA nephropathy?
Immunosuppression
What is the outcome for those with IgA nephropathy?
25% ESRF by 10yrs
What diseases are likely if it is nephritic syndrome?
Post-infectious GN
HSP/IgA
What diseases are likely if it is nephrotic syndrome?
FSGS
Minimal change disease
What is FSGS?
Focal segmental glomerulosclerosis
What signs happen in acute renal failure?
Anuria/oliguria
Hypertension with fluid overload
Rapid rise plasma creatinine
What is AKI?
Abrupt loss kidney function, retention of urea and other nitrogenous waste products and dysregulation of extracellular volume and electrolytes
What is the serum creatinine in AKI?
> 1.5x age specific reference creatinine
What is the urine output in AKI?
<0.5ml/kg for >8hrs
What are the 3 AKI warning scores?
AKI 1: creatinine >1.5-2x ref
AKI 2: creatinine 2-3x ref
AKI 3: serum creatinine >3x ref
What are the 3 M’s of AKI management?
Monitor: PEWS, urine output, weight
Maintain: good hydration
Minimise: drugs
What are the main causes of AKI?
Pre-renal
Perfusion problem
Post-renal
What are intrinsic renal problems that can cause AKI?
Glomerular disease: HUS (haemolytic uremic syndrome) , glomerulonephritis
Tubular injury: acute tubular necrosis (ATN)
Interstitial nephritis
What are causes of acute tubular necrosis (ATN)?
Hypoperfusion
Drugs
What are causes of interstitial nephritis?
NSAID
Autoimmune
Drugs
What are post-renal causes of AKI?
Obstructive uropathies
When does HUS typically occur?
Post-diarrhoea
What typically causes HUS?
Entero-haemorrhagic e.coli
When is the period of risk of HUS?
Up to 14days after onset of diarrhoea
What is HUS a triad of?
Microangiopathic haemolytic anaemia
Thrombocytopenia
AKI/ARF
What are the 3 M’s of HUS?
Monitor: 5 kidney functions
Maintain: IV, renal replacement therapy
Minimise: no antibiotics/NSAIDs
What are the long term consequences of AKI?
BP
Proteinuria monitoring
Evolution to CKD
What are examples of congenital anomalies of the kidney and urinary tract (CAKUT)?
Reflux nephropathy
Dysplasia
Obstructive uropathy
What are causes of CKD in paediatrics?
CAKUT
Hereditary conditions
GN
What may CAKUT be associated with?
Turner
Trisomy 21
Branchio-oto-renal
Prune Belly syndrome
At what GFR would you start to see signs and symptoms in CKD?
<60
How would you diagnose UTI?
Clinical signs +
- bacteria culture from MSSU
- grow on suprapubic aspiration/catheter
What are the clinical findings in younger paediatric patients for a UTI?
More systemic symptoms: fever, vomiting, lethargy, irritability
What are the clinical findings in older paediatric patients for a UTI?
More lower tract symptoms: frequency, dysuria
What can you use to diagnose UTI?
Dipstix
Microscopy
Culture
What is a concerning diagnosis with recurrent UTI?
Vescico-ureteric reflux
Renal scarring
What are the different grades of vescico-ureteric reflux?
Grade 1-5
What investigations can be done for UTI?
US
DMSA (isotope scan)
Micturating cysto-urethrogram (MCUG)
MAG 3 scan
What is the treatment for lower tract UTI?
3 days oral antibiotic
What is the treatment for upper tract UTI/pyelonephritis?
Antibiotics 7-10 days
Prevention
Fluids, hygiene
What are factors affecting progression of CKD?
Late referral Hypertension Proteinuria High intake protein, phosphate, salt Bone health Acidosis Recurrent UTIs
What is the gold standard for BP?
Spigmanometer
What happens to phosphate in kidney disease?
High phosphate as kidneys normally excrete phosphate
High phosphate -> increase PTH
What does a high PTH cause?
Metabolic bone disease
What is the treatment to prevent metabolic bone disease in kidney failure?
Low phosphate diet
Oral phosphate binders
Vitamin D
What is CVS in renal failure?
Accelerated atherosclerosis
