Investigations Flashcards
What causes proteinuria?
- CKD
- Exercise
- Fever
- Pregnancy
- UTI
- High BP
- Nephrotic/nephritic syndrome
What will show blood only on a urine dip?
- Trauma
- Malignancy
- Stones
- Rhabdomyolysis (myoglobin)
What will show blood and protein on a urine dip?
- Glomerulonephritis
- Vasculitis
- Malignant HTN
- UTI (along with leu/nit)
What will show protein on a urine dip?
- Glomerulonephritis
- Amyloid
- Severe HTN
- Diabetic nephropathy
- Renal scarring
What would negative for blood and protein indicate on a urine dip?
- Interstitial nephritis
- Drugs
- Myeloma - cast nephropathy
What would nitrites and leucocytes indicate on a urine dip?
- UTI
- Catheter/stone
- Interstitial nephritis (eosinophils)
What is ACR and PCR?
24 hr urine collection for total protein and creatinine clearance.
To detect and identify proteinuria ACR is the preference as it is more sensitive to lower levels. For quantification and monitoring PCR can be used (ACR in diabetics).
What is proteinuria classified as?
> 150mg/day
What are the clinical findings of diabetic nephropathy?
- Increased GFR
- Microalbuminuria: 3-30mg/mmol
- Microhaematuria
What are the stages of CKD?
- Kidney damage with normal or raised GFR - >90
- Kidney damage with mild decreased GFR - 60-89
- Moderate decreased GFR - 30-59
- Severely decreased GFR - 15-29
- Established kidney failure - <15
When would a CKD stage 3 need to be referred to renal services?
- Microscopic haematuria
- Urinary PCR >45mg/mmol
- Unexplained anaemia
- Abnormal K+>6, Ca < 2.1
- Systemic illness e.g. SLE, arthritis
- Uncontrolled BP (>150/90)
- Fall in GFR >5ml/min in 1yr
- Fall in GFR >15% after ACEi/ARB
When would an immediate referral be required?
- Malignant HTN
- Hyperkalaemia (>7mmol/l)
Urgent: proteinuria with oedema and low serum albumin (nephrotic syndrome)
When would a routine referral be required?
- Dipstick proteinuria and urine PCR >100mg/mmol
- Dipstick proteinuria and microscopic haematuria
- Macroscopic haematuria but urological tests negative
What are the categories used for albumin levels?
A1. Albumin excretion <30mg/24h, A:CR <3mg/mmol
A2. 30-300, A:CR 3-30
A3. >300, A:CR >30
What are the investigations for CKD?
- Bloods: U+E’s, Hb (EPO + ferritin), glucose, decreased Ca, increased phosphate, increase PTH, vit D (BMD)
- Directed tests: ANA, ANCA, anti-GBM
- Urine: dipstick, A:CR or P:CR
- Imaging: USS (size, symmetry etc, in CKD kidneys may be small [<9cm] except in infiltrative disorders [amyloid, myeloma], APKD + DM
- Histology: renal biopsy in progressive, nephrotic syndrome, systemic disease
