This is an abbreviated version of the full GGC Guideline on Nephrotic Syndrome which can be accessed here.
Nephrotic syndrome is defined clinically by:
- Urinary protein losses of >3g/day (~urine protein:creatinine ratio >300mg/mmol)
- Serum Albumin <30g/L
- Oedema (may be mild)
- Dipstick urinalysis
- Clinical history
- Consider and investigate potential causes (Box 1)
Box 1 - Common causes of nephrotic syndrome
|Common causes of nephrotic syndrome
- Multisystem disorders – e.g. Diabetes or Systemic Lupus Erythematous
- Chronic inflammatory disorders (e.g. Inflammatory bowel disease, Rheumatoid arthritis)
- Primary Glomerulonephritis (GN)
- Secondary Glomerulonephritis due to obesity, hypertension or certain drugs
- Malignancy including multiple myeloma
- Review patient observations: blood pressure is often high and oxygen saturations low.
- Outside of critical care areas, measurement of fluid intake/urinary output are often inaccurate. Weigh daily during admission whilst adjusting treatment, ideally using the same scales each time.
- Examine daily for pulmonary oedema. Be wary of skin integrity and risk of infection.
- Urinary protein:creatinine ratio
- GN screen - ANCA, ANA, anti-GBM antibody, rheumatoid factor and C3/C4
- Myeloma screen (in those aged >60 years) - serum electrophoresis, immunoglobulins and Bence-Jones protein
- Virology testing (HCV, HBV, HIV)
- Renal tract ultrasound
Nephrotic syndrome complications: protein malnutrition, hypovolaemia (often iatrogenic), acute kidney injury, thromboembolism and infection.
All cases of nephrotic syndrome should be referred to renal to discuss the need for a renal biopsy.
- Salt restrict to <2g daily, fluid restrict to <1.5L daily.
- Loop diuretics. IV administration is often necessary as absorption can be inhibited by generalised oedema.
- Aim to lose ~1-2kg of body weight per day, using patient-predicted 'dry' body weight as a target.
- Examples of diuretic regimes can be seen below in table 1.
Table 1: Diuretics - initial dose suggestions
||Initial dose suggestion
Currently on diuretics
Give usual dose as a stat IV dose, then give usual daily dose (e.g. 80mg daily, give 80mg IV daily).
Inadequate response options:
- Increase dose
- Add further bolus at ~2pm
- Commence continuous infusion
eGFR >60ml/minute: 40mg daily
eGFR 30-60ml/minute: 80mg daily
eGFR <30ml/minute: 120mg daily
|Ototoxicity, hypokalaemia, hypovolaemia, acute renal decline.
- Only commence on specialist/senior advice.
- Addition of bendroflumethiazide 2.5mg or metolazone 5mg on alternate or each day.
|Profound hypovolaemia, hypokalaemia, hyponatraemia.
- Weak diuretic effect, beneficial in preventing hypokalaemia.
- Amiloride 5mg daily
- Commence anti-hypertensives if necessary to control blood pressure (<140/90mmHg).
- New or uncontrolled hypertension requires further investigations, see GGC Nephrotic Syndrome guidance.
- Examples of anti-hypertensive regimens are shown in table 2.
Table 2: Antihypertensives - initial dose suggestions
||Initial dose suggestion
- Avoid whilst using high dose diuretic due to risk of hypovolaemia induced AKI.
- Ramipril 2.5mg daily
Calcium channel blockers
- Refer patient to dieticians for protein and fat intake advice.
- Commencing lipid-lowering therapy for nephrotic syndrome is not generally recommended in the absence of confirmed aetiology.
- The greatest risk of venous thrombus occurs when serum albumin is <20g/L. Use mechanical measures to reduce risk of DVT in all patients
- Do NOT commence anticoagulation without discussing with renal as this may delay, or substantially increase the risk from, performing a renal biopsy
- All unexplained uPCR results >100mg/mmol should be discussed, non-urgently with renal; out-patient follow-up may be required
- Transient proteinuria often occurs in association with a systemic inflammatory response. A repeat sample in convalescence can clarify
Guideline reviewed: February 2023
Page last updated: March 2023