Objectives
At the end of this session you will be able to:
- approach an OSCE scenario relating to nephrology
- list the basic anatomy and physiology of the kidney
- understand the basic problems, investigation and
treatments that renal patients undergo
- describe the causes, investigations and treatments
for AKI
- describe the main features of CKD
- have an improved understanding of how to tackle
SBAs in nephrology
Not Covered
•Nephritic syndrome
•Pyelonephritis and Upper UTIs
•Lower UTIs
•Nephrolithiasis
•Prostatitis and prostatism
•Polycystic kidney disease
•Renal and bladder neoplasms
•Renal drugs (eg. diuretics)
Stop us if you have any questions!
The Kidneys
•25% of cardiac output
•Two sites of vascular resistance
•Glomerulus has little resistance
•There are three layers to filtration…
The Glomerular Filtration Barrier
•What are the three layers?
The Nephron
•Efferent arterioles continue as vasa recta
•Albumin in efferent arterioles driving water
reabsorption
•Blood flow to distal
nephron is low to
maintain hypertonicity of
loop of Henle (ATN)
The Nephron
•Changes in afferent and efferent vascular tone
alters hydrostatic pressure and GFR
•Avoid NSAIDs (prostaglandins dilate afferent
arterioles – avoid in renal failure)
•NSAIDs effectively cause a mild renal artery
stenosis
•Avoid ACE-Is in renal artery stenosis (AGII
increases GFR by constricting efferent
arteriole)
Any questions?
Renal Transport
•Most substances are controlled by
reabsorption
•Unregulated control
proximally
•Fine control distally
•Some secreted actively
Eg. penicillin
Glucose
•Glucose transport
•Diabetes
•Osmotic diuresis
•Polydipsia
Sodium
•All sodium filtered in Bowman’s capsule
•65% immediately reabsorbed
•25% in ascending LOH
•10% in DCT/CD
depending on fluid status
Phosphate
•Dietary excess
•Kidneys excrete much of it
•Renal failure leads to accumulation
•Oral phosphate binders reduce intestinal
absorption
Potassium
•98% is intracellular
•High intake like phosphate
•Internal potassium homeostasis
•External potassium homeostasis
•Renal failure
•What is calcium resonium?
Insulin? furosemide?
Salbutamol?
Any questions?
What are the functions of our kidneys?
•To produce urine ?
•Removal of waste products and reabsorption of
useful products (eg. glucose, amino acids, etc.)
•Regulation of fluid and electrolyte balance
•Controls BP (renin)
•Maintain acid-base balance (regeneration of
bicarbonate, excretion of H+)
•Stimulates bone marrow (EPO; anaemia of CKD)
•Regulates vitamin D, calcium and phosphate
homeostasis (renal osteodystrophy)
What are the functions of our kidneys?
What can go wrong in renal disease?
What can go wrong in renal disease?
•Uraemia (accumulation of waste products – may need
dialysis)
•Hyper-/ Hypo- volaemia
•Hypertension
•Hyperkalaemia (insulin, dextrose, etc.)
•Metabolic acidosis (oral bicarbonate)
•Normochromic normocytic anaemia*
•Vitamin D deficiency and hypocalcaemia*
•Hyperphosphataemia*
•Renal-bone disease* (osteodystrophy)
•* = more likely to occur in chronic kidney disease
What else can go wrong in renal
disease?
•IMPORTANT! When the glomerulus is
involved….
•Hyperlipidaemia (check lipids)
•Loss of anti-thrombin III (check clotting)
•Loss of complement (beware of infection)
Any questions?
OSCE station
•You are a GP trainee. A 21 year old male
medical student has developed puffy eyes
and ankle oedema after a viral infection he
had last week. Please perform a urine
dipstick and arrange any appropriate
investigations.
What investigations are useful in renal
disease?
•BP
•U+E
•Urinalysis and M,C and S (casts, etc.)
•Urine dipstick
•ABG
•FBC
•BM
•Serum calcium, phosphate, PTH
•Serum lipids
•Clotting (INR)
•Infection screen – CRP, urine and blood cultures, hepatitis screen
•Imaging (renal biopsy, MRI, angiography, US)
What investigations are useful in renal
disease?
What medications are useful in renal
disease?
•Anti-hypertensives
•K+ lowering agents and cardiac protection if required
•Sodium bicarbonate?
•EPO
•Vitamin D analogues
•Phosphate binders
•Statins
•Heparin
•Broad spectrum Abx
•Vaccinations?
•Oral steroids (NS)
•Fluids (? albumin infusion)
•Diuretics (for oedema)
What medications are useful in renal
disease?
Any questions?
What are the three categories of
causes of acute kidney injury?
•Pre-renal (80% of AKI)
•Intrinsic (renal)
•Post-renal
•…best test to differentiate?
What are the three categories of
causes of acute kidney injury?
What are some causes of pre-renal
AKI?
Pre-renal
•Poor perfusion to the kidney
–Haemorrhage
–Dehydration (poor intake, vomiting, diarrhoea)
–Sepsis (septic shock)
–Cardiogenic shock (CCF)
–Burns
–3
rd
space losses
–Clamping during surgery
–Renal artery stenosis (atherosclerosis, fibromuscular dysplasia)
–Drugs (NSAIDs, ACE-Is)
•Progresses to ischaemia and ATN (as vasa recta are poorly
perfused)
What are some key investigations for
each?
•PRE-RENAL …?
–U+Es: high urea to creatinine ratio (exclude other causes of raised
urea eg. GI bleed, rhabdomyolysis)
–Urine chemistry: Na+ <20mmol/l
–Low fractional excretion of Na+ (<1%)
–High urine osmolality (>350 mosm)
•INTRINSIC
–U+Es: low urea to creatinine ratio
–Urine chemistry: Na+ >20mmol/l
–Low urine osmolality (<350 mosm)
–CELL CASTS
•POST RENAL
–Ultrasound
What are some key investigations for
each?
•PRE-RENAL (hypovolemic state)
–U+Es: high urea to creatinine ratio (exclude other causes of raised
urea eg. GI bleed, rhabdomyolysis)
–Urine chemistry: Na+ <20mmol/l
–Low fractional excretion of Na+ (<1%)
–High urine osmolality (>350 mosm)
•INTRINSIC …?
–U+Es: low urea to creatinine ratio
–Urine chemistry: Na+ >20mmol/l
–Low urine osmolality (<350 mosm)
–CELL CASTS
•POST RENAL
–Ultrasound
What are some key investigations to
differentiate between …
•PRE-RENAL
–U+Es: high urea to creatinine ratio (exclude other causes of raised
urea eg. GI bleed, rhabdomyolysis)
–Urine chemistry: Na+ <20mmol/l
–Low fractional excretion of Na+ (<1%)
–High urine osmolality (>350 mosm)
•INTRINSIC
–U+Es: low urea to creatinine ratio
–Urine chemistry: Na+ >20mmol/l
–Low urine osmolality (<350 mosm)
–CELL CASTS
•POST RENAL …?
–Ultrasound
•PRE-RENAL
–U+Es: high urea to creatinine ratio (exclude other causes of raised
urea eg. GI bleed, rhabdomyolysis). Why?
–Urine chemistry: Na+ <20mmol/l
–Low fractional excretion of Na+ (<1%)
–High urine osmolality (>350 mosm)
•INTRINSIC
–U+Es: low urea to creatinine ratio
–Urine chemistry: Na+ >20mmol/l
–Low urine osmolality (<350 mosm)
–CELL CASTS
•POST RENAL
–Ultrasound
What are some key investigations for
each?
What is the general management for
each?
•Pre-renal: ?
•Intrinsic: ?
•Post-renal: ?
What is the general management for
each?
•Pre-renal: ?
•Intrinsic: ?
•Post-renal: ?
What is the general management for
each?
•Pre-renal: ?
•Intrinsic: ?
•Post-renal: ?
•Pre-renal: treat cause
•Intrinsic: depends on cause – SEE NEXT SLIDES
•Post-renal: relieve obstruction
What is the general management for
each?
Chronic Kidney Disease
•Decreased GFR
•Insidious rise in creatinine and urea
•Cf in AKI where there is a sudden rise in
creatinine and urea.
•CKD is initially without specific symptoms and
can only be detected as an increase in serum
creatinine or protein in the urine.
What are the causes of chronic kidney
disease?
What are the causes of chronic kidney
disease?
•75% of cases are due to Hypertension, Diabetes and
Glomerulonephritis
•Classified according to the part of the renal anatomy that is
involved
•1. Vascular - large vessel disease (RAS) and small vessel disease
such as ischemic nephropathy, HUS and vasculitis
•2. Glomerular - Primary Glomerular disease IgA nephritis
• - Secondary Glomerular disease such as
diabetic nephropathy and lupus nephritis
•3. Tubulointerstitial - polycystic kidney disease, drug and toxin-
induced
•4. Obstructive – e.g. bilateral kidney stones and diseases of the
prostate
•Others - pin worms and HIV nephropathy
What are the stages of chronic kidney
disease?
•Stage 1 - Slightly diminished function; kidney damage
with normal or relatively high GFR (≥90 mL/min/1.73
m
2
). Kidney damage is defined as pathologic
abnormalities or markers of damage, including
abnormalities in blood or urine test or imaging studies
•Stage 2 Mild reduction in GFR (60-89 mL/min/1.73 m
2
)
with kidney damage. Kidney damage is defined as
pathologic abnormalities or markers of damage,
including abnormalities in blood or urine test or
imaging studies
•Stage 3 Moderate reduction in GFR (30-59
mL/min/1.73 m
2
)
•Stage 4 Severe reduction in GFR (15-29 mL/min/1.73
m
2
) Preparation for renal replacement therapy
•Stage 5 Established kidney failure (GFR <15
mL/min/1.73 m
2
, or permanent renal replacement
therapy (RRT)
What is dialysis? What are the types?
Dialysis
•Two main types – haemo or
peritoneal
•Hemodialysis uses a machine and an
artificial kidney/ filter to remove the
toxins and excess fluids. This requires
an AV fistula and has to be done 3
times weekly at facility with required
machinery.
•Peritoneal uses the peritoneum which
acts as a natural filter. Requires a
5inch catheter in abdomen. Peritoneal
can be done at home or elsewhere, at
the time that's best for patient.
Dialysate bag needs to be changed
several times daily. Much greater risk
of infection (peritonitis) that
haemodialysis
Any questions?
Single Best Answer Questions
•Not necessarily covered in the lecture (classic
UCL)
Single Best Answer Questions
1A patient with chronic kidney disease is least
likely to have which of the following
metabolic abnormalities?
1Acidosis
2Hyperkalaemia
3Hyperphosphataemia
4Uraemia
5Hypoparathyroidism
Single Best Answer Questions
1A patient with chronic kidney disease is least
likely to have which of the following
metabolic abnormalities?
1Acidosis
2Hyperkalaemia
3Hyperphosphataemia
4Uraemia
5Hypoparathyroidism
Single Best Answer Questions
2A patient presents with a K
+
of 6.7mmol/L. ECG
shows peaked T waves and absence of P waves.
Which of the following is most appropriate in
the initial management of this patient?
1Furosemide
2Dietary restriction of K
+
and amino acids
3Insulin and dextrose
4Calcium chloride and insulin and dextrose
5Calcium resonium
Single Best Answer Questions
2A patient presents with a K
+
of 6.7mmol/L. ECG
shows peaked T waves and absence of P waves.
Which of the following is most appropriate in
the initial management of this patient?
1Furosemide
2Dietary restriction of K
+
and amino acids
3Insulin and dextrose
4Calcium chloride and insulin and dextrose
5Calcium resonium
Single Best Answer Questions
3Which of the following is not routinely
considered as part of a renal screen in the
investigation of new-onset renal failure?
1Complement
2Renal ultrasound
3Caeruloplasmin and serum copper
4Anti-neutrophil cytoplasmic antibodies
5Bence–Jones protein
Single Best Answer Questions
3Which of the following is not routinely
considered as part of a renal screen in the
investigation of new-onset renal failure?
1Complement
2Renal ultrasound
3Caeruloplasmin and serum copper
4Anti-neutrophil cytoplasmic antibodies
5Bence–Jones protein
Single Best Answer Questions
4A 15-year-old boy is referred to the renal clinic by his GP
with a history of worsening haematuria. His mother has
been worried recently that he has been taking illicit drugs
as he has been finding it more difficult to cope at school
and has been falling behind in his schoolwork. He also
seems to be less attentive of late and has become more
withdrawn, watching television on his own with the
volume up loud. Which of the following conditions fits
most closely with the clinical history?
1Alport’s syndrome
2Anderson–Fabry disease
3Goodpasture’s syndrome
4Wegener’s granulomatosis
5Von Hippel–Lindau syndrome
Single Best Answer Questions
4A 15-year-old boy is referred to the renal clinic by his GP
with a history of worsening haematuria. His mother has
been worried recently that he has been taking illicit drugs
as he has been finding it more difficult to cope at school
and has been falling behind in his schoolwork. He also
seems to be less attentive of late and has become more
withdrawn, watching television on his own with the
volume up loud. Which of the following conditions fits
most closely with the clinical history?
1Alport’s syndrome
2Anderson–Fabry disease
3Goodpasture’s syndrome
4Wegener’s granulomatosis
5Von Hippel–Lindau syndrome
Single Best Answer Questions
5A 30-year-old man presents to hospital complaining that
his urine has been very dark recently. He recently has
taken a few days off work with a very sore throat and
coryzal symptoms. Urine dipstick in hospital returns highly
positive for blood and protein. He is admitted for
supportive management and is scheduled for a renal
biopsy, which shows mesangial proliferation with a
positive immunofluorescence pattern. What is the most
likely diagnosis?
1IgA nephropathy
2Post-streptococcal glomerulonephritis
3Rapidly progressive glomerulonephritis
4Membranous glomerulonephritis
5Henoch-Schoenlein purpura
Single Best Answer Questions
5A 30-year-old man presents to hospital complaining that
his urine has been very dark recently. He recently has
taken a few days off work with a very sore throat and
coryzal symptoms. Urine dipstick in hospital returns highly
positive for blood and protein. He is admitted for
supportive management and is scheduled for a renal
biopsy, which shows mesangial proliferation with a
positive immunofluorescence pattern. What is the most
likely diagnosis?
1IgA nephropathy
2Post-streptococcal glomerulonephritis
3Rapidly progressive glomerulonephritis
4Membranous glomerulonephritis
5Henoch-Schoenlein purpura
Single Best Answer Questions
6Which one of the following is an indication
for renal replacement therapy (RRT)
1Pericarditis
2Hyperkalaemia without ECG changes
3Anaemia
4Hypocalcaemia
5Chronic kidney disease stage III
Single Best Answer Questions
6Which one of the following is an indication
for renal replacement therapy (RRT)
1Pericarditis
2Hyperkalaemia without ECG changes
3Anaemia
4Hypocalcaemia
5Chronic kidney disease stage III
Single Best Answer Questions
7Which of the following diseases do
antibodies against type IV collagen in the
glomerular basement membrane cause?
1Wegeners granulomatosis
2Alport’s syndrome
3Goodpasture’s syndrome
4Henoch-Schoenlein purpura
5Scleroderma renal crisis
Single Best Answer Questions
7Which of the following diseases do
antibodies against type IV collagen in the
glomerular basement membrane cause?
1Wegeners granulomatosis
2Alport’s syndrome
3Goodpasture’s syndrome
4Henoch-Schoenlein purpura
5Scleroderma renal crisis
Single Best Answer Questions
8A 71 year old male with chronic kidney
disease develops an acutely hot, tender MCP
joint on her left hand. What is the most likely
diagnosis
1Rheumatoid arthritis
2Reiter’s syndrome
3Gout
4Pseudogout
5Renal bone osteodystrophy
Single Best Answer Questions
8A 71 year old male with chronic kidney
disease develops an acutely hot, tender MCP
joint on her left hand. What is the most likely
diagnosis
1Rheumatoid arthritis
2Reiter’s syndrome
3Gout
4Pseudogout
5Renal bone osteodystrophy
Single Best Answer Questions
9Which one of the following causes of chronic
kidney disease is most associated with a
normal haemoglobin concentration?
1Goodpasture’s syndrome
2Hepatitis C
3Hypertension
4Polycystic kidney disease
5Diabetes mellitus
Single Best Answer Questions
9Which one of the following causes of chronic
kidney disease is most associated with a
normal haemoglobin concentration?
1Goodpasture’s syndrome
2Hepatitis C
3Hypertension
4Polycystic kidney disease
5Diabetes mellitus
Single Best Answer Questions
10A 35 year old lady with IBS is found to be
hypertensive and hypokalaemic following
routine bloods for abdominal pain. She takes
only food supplements as medication. What is
the most likely cause?
1Cushing’s disease
2Peppermint
311-beta hydroxysteroid dehydrogenase deficiency
4Liquorice
5Conn’s syndrome
Single Best Answer Questions
10A 35 year old lady with IBS is found to be
hypertensive and hypokalaemic following
routine bloods for abdominal pain. She takes
only food supplements as medication. What is
the most likely cause?
1Cushing’s disease
2Peppermint
311-beta hydroxysteroid dehydrogenase deficiency
4Liquorice
5Conn’s syndrome
Objectives
At the end of this session you will be able to:
- approach an OSCE scenario relating to nephrology
- list the basic anatomy and physiology of the kidney
- understand the basic problems, investigation and
treatments that renal patients undergo
- describe the causes, investigations and treatments
for AKI
- describe the main features of CKD
- have an improved understanding of how to tackle
SBAs in nephrology
Not Covered
•Nephritic syndrome
•Pyelonephritis and Upper UTIs
•Lower UTIs
•Nephrolithiasis
•Prostatitis and prostatism
•Polycystic kidney disease
•Renal and bladder neoplasms
•Renal drugs (eg. diuretics)