Nephrology Flashcards
(128 cards)
what kind of anaemia do you usually get in CKD
normocytic anaemia
what does anaemia in CKD lead to?
left ventricular hypertrophy
what are the causes of anaemia in CKD?
reduced EPO levels which leads to diminished red blood cell production
reduced absorption of iron
reduced erythropoesis due to toxic effects of uraemia on bone marrow
reduced red cell survival especially in haemodyalysis
blood loss due to capillary fragility and poor lately function
stress ulceration leading to chronic blood loss
how does CKD cause reduced absorption of iron?
hepcidin is an acute-phase reactant
in CKD, hepcidin levels are often increased due to inflammation and reduced renal clearance
elevated hepcidin levels lead to decreased iron absorption from the gut and impaired release of stored iron from macrophages and hepatocytes, reducing the iron available for erythropoiesis
additionally, metabolic acidosis, a common condition in CKD, can inhibit the conversion of ferric iron (Fe³º) to its absorbable form, ferrous iron (Fe²º), in the duodenum → reduced iron absorption.
how is anaemia in CKD managed?
aim for Hb 100 - 120
oral iron should be offered for patients not erythropoiesis agents
if target Hb levels not reached in 3 months patients should be on IV iron
ESAs such as EPO or darbepoetin should be used in those who are likely to benefit in terms of quality of life and physical function
those on ESAs generally require IV iron
what are the complications of nephrotic syndrome?
Increased risk of VTE related to loss of antithrombin III and plasminogen in the urine
DVT, PE , renal vein thrombosis, resulting in a sudden deterioration in renal function
hyperlipidaemia- increasing risk of acute coronary syndrome, stroke etc
chronic kidney disease
increased risk of infection due to urinary immunoglobulin loss
hypocalcaemia (vitamin D and binding protein lost in urine)
what is minimal change disease?
a form of nephrotic syndrome
accounts of 75% of cases in children and 25% of cases in adults
what is the pathophysiology of minimal change disease?
T-cell and cytokine mediated damage to the glomerular basement membrane –> polyanion loss
the resultant reduction of the electrostatic charge - increase glomerular permeability to serum albumin
what are the features of minimal change disease and what is seen on renal biopsy?
nephrotic syndrome
Normotension, hypertension is rare
highly selective proteinuria - only intermediate sized proteins such as albumin and transferrin leak through the glomerulus
renal biopsy - normal glomeruli on light microscopy
electron microsocopy shows fusion of podocytes and effacement of foot processes
how is minimal change disease managed?
oral corticosteroids - majority of cases are steroid responsive - 1mg/kg daily
cyclophosphamide is the next step
what is the prognosis in minimal change disease ?
1/3 have just one episode
1/3 have infrequent relapses
1/3 have frequent relapses which stop before adulthood
what is nephrotic syndrome characterised by?
- Proteinuria (> 3g/24hr) causing
- Hypoalbuminaemia (< 30g/L) and
- Oedema
what are the causes of nephrotic syndrome?
Primary causes: Minimal change disease, focal segmental glomerulosclerosis (FSGS), membranous nephropathy.
Secondary causes: Diabetes mellitus, systemic lupus erythematosus (SLE), amyloidosis, infections (HIV, hepatitis B and C), drugs (NSAIDs, gold therapy).
why is there an increased risk of thrombosis in nephrotic syndrome>
Loss of antithrombin-III, proteins C and S and an associated rise in fibrinogen levels predispose to thrombosis
what are the characteristics and symptoms of nephritic syndromes?
haematuria
hypertension
mild proteinuria <3.5g/day
mild oedema
oliguria and uraemia
what are types of nephritic syndromes?
IgA nephropathy
post strep glomerular nephritis
rapid progressive glomerular nephritis -
anti GBM glomerularnephritis
ANCA vasculitis
what are the types of autosomal dominant polycystic kidney disease?
Type 1 - 85% of cases, chromosome 16, presents with renal failure earlier
Types 2 - 15% of cases - chromosome 4
what is the USS diagnostic criteria for patient with a positive family history?
two cysts, unilateral or bilateral, if aged < 30 years
two cysts in both kidneys if aged 30-59 years
four cysts in both kidneys if aged > 60 years
how is PKD managed?
tolvaptan (vasopressin receptor 2 antagnost
Nice recommends the use of it if:
they have chronic kidney disease stage 2 or 3 at the start of treatment
there is evidence of rapidly progressing disease and
the company provides it with the discount agreed in the patient access scheme.
what is the classification of CKD?
1 Greater than 90 ml/min, with some sign of kidney damage on other tests (if all the kidney tests* are normal, there is no CKD)
2 60-90 ml/min with some sign of kidney damage (if kidney tests* are normal, there is no CKD)
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
When does post step glomerulonephritis develop compared to IgA nephropathy?
PSGN - develops 1-2 weeks after URTI
IgA nephropathy develops 1-2 days after URTI
what is post-streptococcal glomerulonephritis?
Post-streptococcal glomerulonephritis typically occurs 7-14 days following a group A beta-haemolytic Streptococcus infection (usually Streptococcus pyogenes). It is caused by immune complex (IgG, IgM and C3) deposition in the glomeruli. Young children are most commonly affected.
what are the features of post streptococcal glomerulonephritis?
general - headache, malaise
visible haematuria
proteinuria - this may result in oedema
hypertension
oliguria
what would bloods show in post-steptococcal glomerulopnephririts ?
raised anti-streptolysin O titre are used to confirm the diagnosis of a recent streptococcal infection
low C3