renal

Question 1

what is the normal GFR

Answer 1

120-130 ml/min
take as 100ml/min

decraeses with age

Question 2

what are the 2 equations used in calculating renal

Answer 2

Cockcroft-gault equaiton
- uses age, weight, sex, serum creatinine levels
- calculates CrCl

CKD-EPI equation
- uses age, weight and serum creatinine
- increasingly used ot categorise CKD
- estimate of GFR –> eFGR

Question 3

what is the definition of renal failure

Answer 3

it is the deterioration of renal funciton, leading to signs and symptoms
- azotaemia = increased concentration of nitrogenous substances and this reflects a decreased GFR (BIOCHEMICAL PRESENTATION)
- uraemia = toxic effects of the nitrogenous substances (CLINICAL PRESENTATION) plasma urea concentration increase

Question 4

what can renal failure be classified into

Answer 4

1. time of onset (acute - days/weeks vs chronic > 3 months)
2. location (pre-renal, renal and post-renal)

Question 5

criterion for AKI

Answer 5

1. serum cr increased 0.3 mg/dL over 24h
2. serum cr increased x 1.5 ULN within 1 week
3. urine output < 0,5ml/min/kg over past 6h

Question 6

pre-renal
intrarenal and
post-renal

give some examples that can cause renal failure

Answer 6

pre-renal - decreased circulating volume (volume depletion, e.g. vomiting, diarrhoea) and decreased renal perfusion pressure (e.g. renal artery stenosis)

renal - vascular/glomerular, acute tubular necoris (prolonged tubular hypoperfusion leading to intrinsic renal damage( , acute interstitial necrosis (autoimmune)

post-renal - outflow blockage, urethral or bladder blocks s (BPH, strictures)

Question 7

complications of AKI

Answer 7

• metabolic acidosis (clinically presenting as increased resp rate)
• hyperkalaemia
• uraemia (can lead to encephalopathy and pericarditis)
• fluid overload (fluid retention signs - oedema), heart failure and pulmonary oedema

Question 8

what are some causes of chronic kidney disease

Answer 8

diabetic nephropathy
hypertensive nephropathy
glomerulonephritis

Question 9

presentations of CKD

Answer 9

1. fatigue and pallor (anaemia)
2. foamy urine (proteinuria) and haematuria
3. nausea, loss of appetite, pruritus
4. oedema, hypertension (due to fluid retention stimulating the RAAS, renal scarring and subsequent focal renal ischaemia - increased renin and hypertensio further causing glomerular damage, decreased GFR)
5. peripheral neuropahty

Question 10

what are the 2 diagnostics for CKD

Answer 10

1. eGFR < 60 ml/min/1,73m2
2. urine albumin:creatine ration (ACR) > 3mg/mmol

Question 11

biochemical abnormalities in CKD (short term)

Answer 11

1. hypernatremia (decreased Na clearance, leading to oedema and hypertension)
2. urine becomes iso-osmotic (inability to concentrate or dilute the urine)
3. hyperkalemia
4. acidosis - due to renal tubular acidosis and / or high anion gap (AG)

Question 11

long-term complications of CKD (5)

Answer 11

1. bone disease (renal osteodystsrophy)
   - hypocalcaemia: vitamin D activated into calcitriol in the kidney, cannot absorb calcium from diet
   - secondayr hyperparathyroidism: decreased Ca level increased PTH, causing increased bone resorption
   - hyperphosphataemia: decreased secretion, contributing to hypoCa
   - acidosis: due to bone acting as buffer, increased PTH demineralises the bone
2. anaemia - decreased EPO production
3. dyslipidaemia - increasing risk of CVDs
4. hypertension - due to renin secretion
5. endocrine - hyperPRL and hypergonadism (hyperPRL due to decreased renal excretion of PRL and uremic toxins accumulation, impariing the HPA axis)

bone issues
- bone disease (osteomalacia, osteoporosis, osteitis fibrosa cystica, adynamic bone disease)
- metastatic calcification (deposition of calcium phosphate crystal) on soft tissues, arteries and viscera

Question 12

what is the presentation of nephrotic syndrome

Answer 12

1. proteinuria
2. hypoalbuminaemia
3. oedema
4. hyperlipidaemia and lipiduria

Question 13

what is the presentation of nephritic syndrome

Answer 13

1. haematuria (red cell casts)
2. azotemia
3. oligouria
4. mild to moderate hypternsion
5. proteinuria, oedema

Question 14

what is the difference btwn nephrotic and nephritic syndrome

Question 15

what are the causes of nephrotic syndrome (got 5)

Answer 15

1. minimal change disease
2. focal segmental glomerulonephritis
3. membranous nephropathy
   4.. membranoproliferative GN
4. systemic - diabetic, HSP, lupus, GPA/MPA

Question 16

what are the causes of nephritic syndrome (4. 4)

Answer 16

children:
1. IgA nephropathy (Berger’s disase)
2. acute proliferative GN (post-strep),
3. Henoch-Scholein Purpura (HSP)
4. HUS

adults
1. rapidly progressive GN (cresenteric, RAPGN)
- goodpasture (type 1), anti-GBM (type 2)
2. membranoproliferative GN
3. SLE, IE
4. ANCA-mediated vasculitis

Question 17

obstructive causes of kidney - go

Answer 17

increases risk of stone formtaion and infection, and can lead to permamny renal atrophy if not cleared

congenital or acquired
congenital can be: posterior urethral valves or urethral stricture
acquired can be:
tumours, BPH
renal stones
pregnancy uterine collapse
neutrogenic (e.g. spinal cord issues)

Question 18

are men or female more likely for renal sontes

Answer 18

arise from naywhere in the urinary tract but mainly from kidney
male, 30-60y

genetics can play a rile
- primary hyperoxaluria or cystinuria