Renal presentations
Urine Asymptomatic haematuria
Haematuria Aetiology
Aetiology 1. IgA nephropathy
Renal congenital: PKD, trauma, infection: Commonest GN in developed world
pyelonephritis, neoplasm, immune: GN Signs + symptoms
Extra-renal trauma: stones/catheter, Young male w/ episodic macroscopic
infection: cystitis, prostatitis, urethritis, haematuria occurring a few days after URTI
neoplasm: bladder, prostate, drugs:
Rapid recovery between attacks
NSAIDs, furosemide, ciprofloxacin,
cephalosporins High IgA can occasionally nephritic
Ix biopsy IgA deposition in mesangium
Proteinuria Mx steroids/cyclophosphamide if reduced
30mg/dL = + renal function
300mg/dL = +++ 2. Thin basement membrane
PCR < 20mg/mM = normal Autosomal dominant
PCR > 300mg/mM = nephrotic Commonest cause of asymptomatic
Aetiology DM, minimal change, haematuria
membranous, amyloidosis, SLE Signs + symptoms
Persistent, asymptomatic microscopic
Microalbuminaemia
Albumin: 30-300mg/24h haematuria, very small risk of ESRF
Aetiology DM, high BP, minimal change 3. Alport syndrome
GN 85% X-linked recessive
Casts Haematuria, proteinuria progressive RF
RBC glomerular haematuria SNHL, lens dislocation + cataracts, renal
WBC interstitial nephritis/pyelonephritis ‘flecks’
Tubular ATN Females: haematuria only
Urea + Creatinine Haematuria Mx
Creatinine Testing
Synthesized during muscle turnover Urine dipstick is the test of choice for
Freely filtered + small portion secreted by detecting haematuria
PCT Persistent non-visible = blood present
Increase muscle mass high creatinine: 2/3 samples tested 2-3 weeks apart
age, sex, race Renal function ACR, PCR + BP should be
Plasma Cr doesn’t rise above normal until
tested
50% reduction in GFR
MCS
Urea
Produced from NH3 by liver in ornithine Urgent referral (i.e. w/i 2 weeks)
cycle Aged ≥ 45 yrs + unexplained visible
High w/ protein meal (e.g. upper GI bleed,
haematuria w/o UTI
supplements)
Low w/ hepatic impairment
OR visible haematuria that
10-70% absorbed back: depends on urine persists/recurs after Rx for UTI
flow Aged ≥ 60 yrs + unexplained non-visible
Low flow High urea reabsorption (e.g. haematuria + either dysuria/raised WCC
dehydration) Non-urgent referral
Interpretation
Aged ≥ 60 yrs + recurrent/persistent
Isolated high urea = low flow (e.g. unexplained UTI
hypoperfusion/ dehydration)
High urea + creatinine = low filtration (i.e.
renal failure)
Urine Asymptomatic haematuria
Haematuria Aetiology
Aetiology 1. IgA nephropathy
Renal congenital: PKD, trauma, infection: Commonest GN in developed world
pyelonephritis, neoplasm, immune: GN Signs + symptoms
Extra-renal trauma: stones/catheter, Young male w/ episodic macroscopic
infection: cystitis, prostatitis, urethritis, haematuria occurring a few days after URTI
neoplasm: bladder, prostate, drugs:
Rapid recovery between attacks
NSAIDs, furosemide, ciprofloxacin,
cephalosporins High IgA can occasionally nephritic
Ix biopsy IgA deposition in mesangium
Proteinuria Mx steroids/cyclophosphamide if reduced
30mg/dL = + renal function
300mg/dL = +++ 2. Thin basement membrane
PCR < 20mg/mM = normal Autosomal dominant
PCR > 300mg/mM = nephrotic Commonest cause of asymptomatic
Aetiology DM, minimal change, haematuria
membranous, amyloidosis, SLE Signs + symptoms
Persistent, asymptomatic microscopic
Microalbuminaemia
Albumin: 30-300mg/24h haematuria, very small risk of ESRF
Aetiology DM, high BP, minimal change 3. Alport syndrome
GN 85% X-linked recessive
Casts Haematuria, proteinuria progressive RF
RBC glomerular haematuria SNHL, lens dislocation + cataracts, renal
WBC interstitial nephritis/pyelonephritis ‘flecks’
Tubular ATN Females: haematuria only
Urea + Creatinine Haematuria Mx
Creatinine Testing
Synthesized during muscle turnover Urine dipstick is the test of choice for
Freely filtered + small portion secreted by detecting haematuria
PCT Persistent non-visible = blood present
Increase muscle mass high creatinine: 2/3 samples tested 2-3 weeks apart
age, sex, race Renal function ACR, PCR + BP should be
Plasma Cr doesn’t rise above normal until
tested
50% reduction in GFR
MCS
Urea
Produced from NH3 by liver in ornithine Urgent referral (i.e. w/i 2 weeks)
cycle Aged ≥ 45 yrs + unexplained visible
High w/ protein meal (e.g. upper GI bleed,
haematuria w/o UTI
supplements)
Low w/ hepatic impairment
OR visible haematuria that
10-70% absorbed back: depends on urine persists/recurs after Rx for UTI
flow Aged ≥ 60 yrs + unexplained non-visible
Low flow High urea reabsorption (e.g. haematuria + either dysuria/raised WCC
dehydration) Non-urgent referral
Interpretation
Aged ≥ 60 yrs + recurrent/persistent
Isolated high urea = low flow (e.g. unexplained UTI
hypoperfusion/ dehydration)
High urea + creatinine = low filtration (i.e.
renal failure)