Clinical Features
Diagnostic and Clinical Features:
- Heavy proteinuria (3+/4+ on dipstick) or urine protein:creatinine (PCR) >200 mg/mmol.
- Hypoalbuminaemia: serum albumin <25 g/L
- Generalised oedema:
Peri-orbital swelling, noticed particularly in the morning
Ankle and lower limb swelling – pitting oedema Abdominal swelling and scrotal/vulval oedema
Typical versus atypical features
Typical Features
Age 1-10 years
Normotensive
Normal creatinine
Microscopic haematuria (≤25%)
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Atypical Features
<1yr, >10years Hypertensive
Macroscopic haematuria
+/- Family history of nephrotic syndrome
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Those presenting with atypical features are more likely to be unresponsive to steroid treatment.
Initial Assessment
Initial clinical assessment to include:
- Height and weight
- Calculation of body surface area - √([Ht (cm) x Wt (kg)] / 3600) Cardiovascular status and perfusion
- Heart rate
- Blood pressure
- Capillary refill time
- Jugular venous pressure (JVP) or presence of hepatomegaly – particularly in older children
- Assessment of oedema - Lower limb
- Spine – sacral
- Ascites
- Scrotal/vulval
- Assessment of fluid status
- Fluid overload
(tachycardia; hypertension; warm peripheries; respiratory distress; hepatomegaly; raised JVP)
- Euvolemia
- Hypovolemia
(tachycardia; hypertension; cool peripheries; delayed capillary refill time; severe abdominal pain)
Note: Hypovolemia is relatively common and can lead to serious complications. Tachycardia and hypertension can be present in both fluid overload and hypovolemia. Peripheral and central perfusion remain the most discriminatory physical findings with warm peripheries and possible respiratory distress in fluid overload, and cool peripheries with delayed capillary refill time in hypovolemia.
Initial Investigations
Investigations to be performed in all children.
Children with nephrotic syndrome can be difficult to bleed due to oedema, therefore only take the following bloods on initial assessment.
Bloods:
- FBC
- U&Es – including bicarbonate; chloride
- Bone profile – calcium; phosphate; serum albumin
- LFTs
- Varicella IgG
- Vitamin D
Urine:
- Urinalysis including glucose - document proteinuria and the presence of any haematuria
- Urinary protein:creatinine ratio (PCR)
- Urinary sodium concentration – helpful in aiding fluid status
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Further investigations to be performed in children with atypical features:
- ASOT – may be elevated in Streptococcal throat infection
- Anti-DNaseB – may be elevated in Streptococcal skin/throat infection
- C3/C4 – low C3 levels may be seen in post-Streptococcal/infectious glomerulonephritis (PIGN), C3 glomerulopathy (previously called MPGN types I-III), systemic lupus erythematosus (SLE)
- Hepatitis B status in children at high risk: family history of hepatitis B infection or history of travel in endemic areas.
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Indications for discussion with a paediatric nephrologist
If there are any of the following features, the child/young person should be discussed with a paediatric nephrologist:
- Any atypical features
- Before giving IV albumin (see section)
- Any complications: the nephrotic state can be complicated by hypovolaemia; thrombosis and infection
- If not responsive to Prednisolone after 4 weeks
Management
Fluid Restriction
Fluid restriction may also be helpful in limiting the increase in oedema. However, if a child is felt to be intravascularly deplete and peripherally shut down (cool peripheries, prolonged capillary refill time, tachycardic, and/or hypotensive) then fluid restriction may increase the risk of thrombotic episodes so the need for a fluid restriction should be evaluated carefully and reviewed daily. Discussion with nephrology is advised if in doubt.
General Recommendations for fluid restriction:
<5 years: 750 mL per day
>5 years: 1000 mL per day
These restrictions should always be lifted once the child goes into remission. An increased urine output is often an early sign of entering remission.
Remember hidden fluids may be present in certain foods (e.g. soups, yogurts, ice lollies, fruit).
Dietary Advice
A low salt diet limits thirst and also prevents further fluid retention and oedema.
Dietetic advice regarding calorie control should be given whilst on steroids. Dietetic restrictions can be lifted once in remission.
Drug Treatment
Drug treatment in children with INS can prove challenging.
Pharmacy advice is helpful in many aspects of appropriate drug treatment in NS:
- Drug dosing and administration
- Appropriate formulation
- Steroid treatment and tapering regimen
- Antibiotic prophylaxis
- Gastro-protection
- Vitamin D supplementation
A Renal Medication Information Booklet should be issued to all patients.
Prednisolone
Prednisolone is the drug of choice in INS. Patients should be issued with a steroid warning card.
Dose
Currently an 8-12-week initial course is recommended.
Note – increased risk of adrenal suppression after 4 weeks of high dose steroids. See below for further comment.
Prednisolone dose is based on body surface area (BSA).
(BSA = √([Ht (cm) x Wt (kg)]/3600) Mosteller method.
Height is essential to calculate BSA.
- 60 mg/m2/day for 4 weeks (maximum 60 mg/day)
- 40 mg/m2 on alternate days for 4 weeks (maximum 40 mg/day)
- Then reduce dose by 5-10 mg/m2 each week for another 4 weeks, then stop.
An alternative regimen is to stop after 8 weeks total. Risk of adrenal suppression should be considered.
Dosing regimen for initial presentation for ranges of BSA, with rounding of dose can be found in Appendix 2.
Monitoring
Monitor BP and urine PCR.
If proteinuria persists beyond the first 4 weeks of steroid treatment, then children should be referred to the paediatric nephrology team.
Adverse effects
Steroids can be associated with stomach ache, nausea, vomiting, indigestion, increased appetite, weight gain, trouble sleeping and nightmares, low mood, emotional lability, and changes in behaviour.
Long-term use of prednisolone can result in adrenal suppression, short stature, cataracts, and hypertension.
For all first presentations, a steroid warning card should be issued, as required for steroid usage > 6 weeks and adrenal suppression guidelines should be followed. Adrenal suppression secondary to exogenous glucocorticoid - guidance for children onlong term steroid therapy (scot.nhs.uk)
Availability & Prescribing
Prednisolone liquid (10 mg/mL) can be sourced through pharmacy. The use of liquid prednisolone (rather than tablets) in young children has improved compliance considerably and outweighs the cost.
Prednisolone dispersible 5 mg tablet
Prednisolone plain tablets: 1 mg, 2.5 mg, 5 mg, 10 mg, 20 mg, 25 mg, 30 mg (these contain lactose)
Prednisolone enteric-coated (EC) tablets: 1 mg, 2.5 mg, 5 mg (these contain lactose)
Antibiotic Prophylaxis – Phenoxymethylpenicillin (Pen V)
Infection remains the main cause of death in children with nephrotic syndrome. Whilst nephrotic, children are at increased risk of infection, particularly with encapsulated organisms such as Pneumococcus. Recommendations on the use of antibiotic prophylaxis vary as there is no strong evidence of its benefit. Grossly oedematous children are at particular risk of cellulitis/peritonitis and may benefit from antibiotic prophylaxis.
Our policy is to give Phenoxymethylpenicillin prophylaxis only in children who are severely oedematous/ascitic on first presentation.
Note Penicillin V is generally not recommended in relapses.
Age <1 year: 62.5 mg twice daily
Age 1-5 years: 125 mg twice daily
Age ≥6 years: 250 mg twice daily
If penicillin allergic, consider Erythromycin as per BNFc
Pneumococcal vaccination is recommended for children with NS not previously vaccinated. See Vaccination advice below.
Gastroprotection
Protection against steroid-induced gastric irritation should be started at the time of commencing steroids.
Use a proton pump inhibitor (PPI) as per local policy, dosing as per BNFc.
Consider stopping the PPI once the Prednisolone dose is weaned to 10 mg on alternate days in the absence of gastric symptoms.
Diuretics
Whilst not routine, there may be a role for diuretics in persistent oedema with no hypovolemia. Discussion with nephrology is advised.
Diuretics should only be used in a child/young person who is not clinically hypovolaemic. Furosemide alone may be tried initially. However, if oedema is severe, the addition of spironolactone or amiloride may be more effective.
- Furosemide: 0.5-1 mg/kg twice daily orally. Give second dose before 6pm to avoid the effect disturbing sleep.
- Spironolactone: 0.5 -1 mg/kg twice daily orally; or Amiloride: 0.1-0.2mg/kg twice daily orally
Patients on diuretics need close and regular review as they are at risk of intravascular depletion if entering remission. If discharged, review within 48-72 hours is advised to assess the ongoing need for diuretics. A maximum 5 day supply is advised. Review should include clinical assessment with weight measurement, urine PCR quantification and assessment of renal function.
If diuretics are felt to be required beyond 7 days then there is an additional need to monitor ionised calcium levels.
Vitamin D
This is measured as levels of 25-hydroxyvitamin D, see Table 1 for definition.
Definition
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Serum 25-hydroxyvitamin D
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Severe deficiency
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<12 nmol/L
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Deficiency
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12-50 nmol/L
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Insufficiency
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50-75 nmol/L
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Sufficiency
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>75 nmol/L
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Table 1: Definition of serum levels of 25-hydroxyvitamin D
Follow local policy for management of vitamin D deficiency and treatment.
Manage Complications
Hypovolaemia
Hypovolaemia in an oedematous child is common, particularly on first presentation. Hypovolaemia is associated with a risk of thrombosis.
Hypovolaemia management can be challenging. Seek nephrology input early on.
Consider fluid repletion if the initial assessment suggests hypovolemia. This can be delivered with 5% Albumin (5-10 mL/kg). The rate will vary depending on clinical severity and this is generally given over 1- 4 hours.
Severe Oedema
Albumin infusion
Albumin infusions are associated with a significant risk of fluid overload and pulmonary oedema.20% albumin should not be given out with daytime hours and only with medical supervision readily available.
- Ideally this should be done with adequate nursing supervision, in a high dependency unit, if possible and only following consultation with the on-call paediatric nephrologist.
- Estimate dry weight to establish dose of albumin. It is safer to round down and give less.
- Administer 1 g/kg (5 mL/kg) 20% albumin over 4-6 hours. In severe oedema, or if a child has previously been treated for hypovolaemia, give over 6 hours.
- Administer 1 mg/kg IV furosemide mid-way through infusion and a further 1 mg/kg IV furosemide at end of infusion. Prior to end dose, carry out a clinically assessment of the child to assess if it is clinically safe for a second dose of furosemide. If the child remains peripherally cool to touch with reduced perfusion then it may be reasonable to omit the second dose of furosemide provided their lung fields are clear with no tachypnoea, and no tachycardia or hypertension.
See Nursing Albumin Standard Operating Procedure(SOP)
Hypertension
Most children presenting with nephrotic syndrome are normotensive when their BP is checked in the setting of them being relaxed and using an appropriate sized cuff on an upper limb. If the BP is truly elevated, it is often associated with oedema and should resolve when oedema subsides. Adhering to the set fluid restriction and a low salt diet is helpful. Fluid removal using diuretics will help reduce BP. If it persists, antihypertensives may be required in the short term. However, this should be discussed with a paediatric nephrologist.
Persistent hypertension (systolic BP >95th centile) can be treated with longer acting agents such as Amlodipine. This is particularly useful in young children as it is a once daily dose and comes in a liquid formulation. Dose: start at 0.1mg/kg; can be increased incrementally (ideally weekly) to 0.4mg/kg per day (max 10 mg daily).
Children who have been discharged on antihypertensives should be reviewed in clinic within a week from discharge as their BP may return to normal as the oedema subsides.
Thrombosis
Patients with nephrotic syndrome are predisposed to a pro-coagulant state due to loss of anti-thrombin III in the urine and intravascular depletion. Thrombosis is a rare (occurring in approximately 3% of patients), majority within the venous circulation, but significant complication of nephrotic syndrome, contributing to significant morbidity and mortality.
Thromboses may develop in the locations including the extremities (i.e. deep venous thrombosis), renal vasculature (i.e. renal vein thrombosis), pulmonary vessels (i.e. pulmonary embolism), cerebral venous sinuses (i.e. cerebral venous sinus thrombosis) – headache being the first symptom. Any clinical features which point towards a thrombosis warrants an urgent clinical review and should be followed up by prompt imaging studies. In the event of a suspected thrombus, refer urgently to paediatric nephrology.
Vaccination
Live vaccines should not be given to children who are on, or have recently been taking immunosuppressive medication, as defined by our immunisation guideline: Immunisation guideline for children with chronic kidney disease
Please note, particular consideration needs to be given to the following vaccines:
Pneumococcal Polysaccharide Vaccine (PPV) 23 Valent
- Recommended for all children with NS over 2 years.
- Confirm prior vaccination with the pneumococcal conjugate vaccine (PCV) 13 valent.
- Request GP to administer 23 valent if the child has previously had the 13 valent as part of routine childhood immunisations. Include this in the child’s discharge letter.
- If the child has not had the 13 valent vaccine, refer to the vaccination schedule as per immunisation of unknown/incomplete immunisation.
- Repeat PPV 23 vaccination every 5 years.
Varicella Zoster Vaccine
Chicken pox in children who are, or have been on immunosuppressive medication, can be a very serious illness. Establish varicella status with parents on admission and document this in the patient’s case notes.
Varicella zoster IgG should be taken with bloods on initial presentation. If negative with a positive history of having had chicken pox, this will need to be repeated as it may be a false negative.
Varicella status confirmed non-immune (VZIgG negative)
- For all children confirmed VZIgG negative, consider active immunisation with Varicella-zoster vaccine when off all immunosuppressive therapy.
Chicken pox contact
For children who are not immune to chicken pox (VZIgG negative) and who are immunosuppressed (classified as being on ≥2 mg/kg/day of prednisolone for >1 week or 1 mg/kg/day for >1 month or on second line immunosuppression), it is important that they contact their healthcare provider if they have had a close contact exposure (deemed to be a household contact or within the same class at nursery or school). They will need to attend the hospital.
The guidance for VZ prophylaxis has changed recently due to the shortage of Varicella Zoster Immunoglobulin (VZIG) within the UK.
Options:
- Oral Aciclovir or Valaciclovir treatment for 7 days. This should be started on days 7-14 post Evidence suggests that giving aciclovir immediately following exposure is actually associated with an increased incidence and severity of varicella infection, hence the recommendation for a delay. Dosing of Aciclovir and Valaciclovir is as per BNFc. This is the current option of choice.
- Varicella-zoster immunoglobulin (VZIG) can be given if readily available. Dosing as per BNFc. VZIG would be preferential in those with significant renal impairment (whereby aciclovir may be contraindicated due to risk of nephrotoxicity) or intestinal malabsorption disorders (e.g. inflammatory bowel disease).
Chicken pox infection
All children who report a rash thought to be chickenpox should be reviewed in hospital. If chickenpox is confirmed then the child should be admitted and treated appropriately. If they remain clinically well then they may be able to be treated with a course of treatment-dose oral aciclovir. Unwell children should be given treatment-dose IV aciclovir.
Seasonal Influenza
Annual seasonal flu vaccination is required but children/young people with NS should be given a non-live injection and NOT the live nasal vaccination. Please include this in the discharge letter.
Ongoing care
Admission and inpatient management is advisable with the first presentation. Regular review thereafter to monitor for complications and assessment of oedema is recommended. The frequency of follow-up will be guided by the patient’s clinical status.
Parental teaching and education
INS is defined by relapses and remissions. Families need education on how to manage the condition on discharge, and how to recognise and manage relapses. Education should commence as soon as possible following admission.
Parents should be taught to test urine daily on discharge with Albustix® using a first morning urine sample.
Areas of education:
- Urine testing and recording.
- Medicationadministration – ensure the child is taking the medication from their parents prior to discharge. Ensure parents are aware of the correct dosing and timing of medication.
- Fluid restriction – ensure parents are aware of daily fluid allowance and to get in touch with the unit when their child starts to pass more urine, and urinary protein starts to reduce on home testing. As children respond to steroids and go into remission, they can often pass large volumes and are at risk of becoming dehydrated if still on a fluid restriction. This risk is greater if they are also on diuretics.
- Outpatient review - children should be seen in clinic within one week of discharge or earlier if discharged home on diuretics.
Web links for patient information on Nephrotic Syndrome (NS)
InfoKid provides information for parents and carers regarding various kidney conditions in infants, children and young people http://www.infokid.org.uk
There are links to the Medicines for Children website regarding medications used in Nephrotic Syndrome: Leaflets – Medicines For Children
https://www.kidneykids.org.uk/ Kidney Kids Scotland have set up a Facebook page which aims to connect families if patients with nephrotic syndrome.
Nephrotic Syndrome Trust- NeST NeST | Nephrotic Syndrome Trust (nstrust.co.uk)
Discharge planning
Discharge planning and parent education should begin soon after admission and diagnosis. A checklist can be used and a printed copy can be provided to the patient and family at discharge (Appendix 1).
Nursing
See Nursing Albumin SOP
Response to treatment
Most children with nephrotic syndrome will respond to steroid treatment within 2-4 weeks. A remission is defined as 3 or more days of dipstick testing either showing trace or negative for protein. Up to 80% of patients enter remission within 14 days on steroids.