Paediatric Nephrology Flashcards
Breaking it Down
Haematuria/Proteinuria = Glomerular disease
glomerular disease = nephrotic/nephritic syndromes
Acute Kidney injury = Haemolytic uraemic syndrome
Chronic Kidney injury
Developmental anomalies - Reflux nephropathy
the nephron and GFR
Nephron receives 25% of CO/minute
GFR - neonate = 20-30ml/min/1.73m^2
by aged 2 this increases to around 90-120
5 kidney Functions - Do not change in adulthood
Waste - Urea and creatinine
Ion balance - Na/Cl/K
Acid base control - Bicarb
Endocrine - RAAS/PTH/activation of Vit D
Glomerulonephropathy
Blood and Protein in varying volumes will dictate: Clinical presentation and may suggest Dx
However:
damage to one area of GFB affects the other components too
HAEMATURIA = GLOMERULAR INJURY
Acquired glomerulonephroathy
M/C damaged = Epithelial cells (podocytes)
minimal Change, FSGN, Lupus
Basement Membrane - Membranous GN, MPGN, PIGN
Endothelial Cell - PIGN, HUS, MPGN, Lupus
Mesangium - IgA, HP, Lupus
Congenital is more rare
Podocyte Cytoskeleton
Basement membrane proteins
Endothelial/microvascular integrity
Definition of Nephrotic Syndrome
Nephrotic range proteinuria
Hypoalbuminaemia (normal is 36-44g/ - oedema at 25-30)
Oedema ( hypoalbuminaemia –> lack of oncotic pressure and vessels leak)
Typical Presentation of Nephrotic Syndrome
2.5 year old
Gastroenteritis 10 days ago
3-4 day hx of swollen face (worse in mornings) one eye closed in morning, swollen legs
No allergies
Great grandmother had a nephrectomy
Presentation of Nephropathy
Looks well but a bit pale Periorbital oedema, pitting in legs, ascities, small pleural effusions BP Normal or mildly raised FROTHY URINE
Ix for Nephrotic Syndrome
FBC - Albumin Low Creatinine normal
Urine Dip - ++++ protein (24hr urine collection should be done + protein creatinine ratio)
BP
Renal function
Common Causes of Nephrotic Syndrome
Minimal Change GN
Typical features - 2-5yrs, Norm BP, Micro haematuria Normal Renal Function
Atypical features - Suggestions of autoimmune, Abnormal Renal Function, Steroid resistance
ONLY CONSIDER Bx IF ATYPICAL
Mx of nephrotic syndrome
Typically 8weeks prednisolone
S/E Varicella status Pneumococcal Vaccination CUSHINGS BEHAVIOUR
Common Causes of Nephrotic Syndrome
Minimal Change GN
Typical features - 2-5yrs, Norm BP, Micro haematuria Normal Renal Function
Atypical features - Suggestions of autoimmune, Abnormal Renal Function, Steroid resistance
ONLY CONSIDER Bx IF ATYPICAL
Mx of nephrotic syndrome
Typically 8weeks prednisolone
S/E Varicella status Pneumococcal Vaccination CUSHINGS BEHAVIOUR
Why would nephrotic syndrome be steroid resistant
Focal segmental GN - loss of podocytes and progressive inflammation with sclerosis
Congenital presentation also
Microscopic Haematuria Confirmation
If you investigate and there is more than tract on 2 or more separate occasions
(Macroscopic is easier as you will see the blood)
Haemaglobinuria
Stix positive + Microscopy Negative
Persistent haematuria + proteinuria =
Glomerular disease
causes of Microscopic haematuria
Glomerulonephritis: Post infective, IgA/HSP, MPGN, Lupus, ANCA positive vasculitis
UTI/Trauma/Stones
Benign recurrent haematuria (family Hx
Alports syndrome
Thin basement membrane
HUS
Nephrotic Syndrome
MCGN
FSGN
Wilm’s tumour
Sickle cell
Exercise
Clotting abnormalities
Causes of Macroscopic haematuria
Glomerulonephritis: Post infective, MPGN, Lupus, IgA/HSP
UTI
Trauma
Stones
Benign recurrent (FHx) Alports
HUS
Wilm’ tumour
Clotting abnormalities
What is nephritic Syndrome (clinical Diagnosis)
Describes glomerulonephritis
Haematuria and Proteinuria
Reduce GFR - Oliguria, Fluid overload (raised JVP, oedema), Hypertension, Worsening renal failure= Rapidly progressing GN)
Intrarenal Cause of acute kidney injury (AKI)
Causes of GlomeruloNEPHRITIS
PIGN HSP/IgA MPGN Lupus ANCA positive vasculitis
Acute post infective glomerulonephritis
Usually caused by a Group A strep
Beta Haemolytic
Most commonly in the throat or on the skin
Dx of PIGN
Bacterial Culture (e.g. throat swab)
Positive ASOT - anti-streptolysin O Titre (Ab against strep)
Low C3 that normalises
Bx not required at this moment
Remember possible DDx - IgA/Lupus/MCGN
Treamtnet of PIGN
Abx
Supportive of renal Function
Treat overload.Hypertension - Diuretics
Condition is mostly self limiting and should not come back
IgA nephropathy
M/C glomerulonephritis
1-2 days after URTI
usually in older children and adults
Dx of IgA
Clinical Dx based on…
Recurrent macroscopic haematuria
+/- microscopic
varying degrees of proteinuria
Clinical picture
negative autoimmune workup
normal compliment –> confirm with Biopsy
Pathogenesis
Circulating IgA1 –> Abs made against IgA1 –> immune complexes develop and circulate –> complexes develop in situ in kidneys –> immune response results in injury
Henoch-Schonlein Purpura
Age of onset - 5-15 years
Dx of HSP
MANDATORY - palpable purpura \+ one of the 4 1. Abdo pain 2. Renal Involvement 3. Arthritis or arthralgia 4. Bx for IgA deposition
IgA vasculitis
Most common child hood vasculitis –> small vessel
IgA nephropathy/IgA vasculitis with nephritis (HSP)
What triggers IgA vasculitis
1-3 days post Viral Infection (70% URTI)
Streptococcus, Drugs
Duration - 4-6 weeks
Causes mesangial Cell injury
Treatment of IgA vasculitis
Symptoms - Joints and Gut
Glucocorticoid therapy - Not helpful with renal disease but may help GI situation
Immunosuppression - Trial in Mod to Severe renal dysfunction
Long term hypertension and Proteinuria screening
Small Summary so far
NEPHRITIC SYNDROME
PIGN/HSP/IgA
increasing haematuria
Intravascular overload
Hypertension
NEPHROTIC SYNDROME
FSGN/minimal Change
Increasing proteinuria
Intravascular depletion
Acute kidney injury
Abrupt loss of kidney function, resulting in the retention of urea and other nitrogenous waste products and in the dysregulation of extracellular volume and electrolytes
Some Feature of AKI
Anuria/Oliguria <0.5ml/Kg/hr for 8 hours
Hypertension with fluid oveload
Rapid rise in PLASMA CREATININE (1.5 x age reference)
Interpreting AKI severity
AKI 1 - Creatinine 1.5- 2 x reference range
AKI 2 - Creatinine 2-3 x reference range
AKI 3 - Creating > 3 x reference range
AKI Management
The 3 Ms of prevention
Monitor - urine output, PEWS, BP, Weight
Maintain - good hydration
Minimise - Drugs
Causes of AKI
Intra-renal Problems: Glomerular disease (HUD, GN)
Tubular injury (acute tubular necrosis) - Hypoperfusion/drugs
Interstitial nephritis - NSAIDs, autoimmune
Post renal = Obstructive
Haemolytic uraemic syndrome
Typically post diarrhoea (enterohaemotthagic E. coli - EHEC) - Verotoxin Producing/ Shigatoxin (VTEC/STEC)
other causes may involve - pneumococcal infection/drugs
Presentation of HUS
E. Coli 0157:H7 serotype
Period of HUS risk - up to 14 days post diarrhoea
BLOODY DIARRHOEA IS A MEDICAL EMERGENCY IN CHILDREN (blood = Thrombotic)
child will develop Diarrhoea, pain fever and possibly vomiting - blood will come 1-3 days later
HUS Triad
Microangipathic haemolytic anaemia
Thrombocytopaenia
AKI
Renal Transplant required in 30-40% of cases
DDx for HUS
ITP
3Ms of HUS
Monitor - 5 key kidney functions
Be aware of other organs
Maintain - IV normal saline and fluid - renal replacement therapy
Minimise - NO ANTIBIOTICS
Long term Consequences of AKI
Blood pressure
Proteinuria monitoring
Evolution to CKD
Urinary Tract infection
Making the Dx
MSSU/Clean Catch? consider catheterisation
Suggestive Tests
Urine Dip - Leucocyte esterase activity - Unreliable <2
Microscopy - Pyuria > 10 wBC per cubic mm
Culture >10^5 colony forming units - E. Coli
possible organisms causing UTI in children
E. Coli
Klebsiella
Proteus (stones)
Step Faecalus
Worry about Scarring -Triad
UTI
VUR
Vulnerable Kidney
Scarring is found in the middle of it all
VUR = Vesicoureteric reflux - Graded 1-5
1 - ureter only 2 - ureter, pelvis, Calyces 3 - dialation of ureter 4 - Moderate/advancing dilation of ureter (involves other structures/may be torturous) 5 - Gross Dilation/Tortuosity
Screening for scarring
Imaging of the renal tract
Screening children at risk of scarring - Reflux nephropathy
Capture those with renal dysplasia
Urological abnormalities/unstable bladder - Voiding dysfunction
Guidlines on who to investigate
- Upper tract symptoms
Younger
Recurrent
Renal Investigation
Ultrasound - Structure
DMSA (isotope scan) - Scarring and function
Good hydration required
MAG 3 scan - Dynamic flow/obstruction
Good hydration
Requires to be very still
Treatments of UTI
Lower tract - 3 days oral Abx - Trimethoprime, Co-amoxiclav, Caphalosporin
Upper tract/Pyelonephritis- Abx for 7-10 days - oral if systemically well
IV - 3rd generation Cephalosporin or Co-amoxiclav, IV Aminoglycosides effective (good renal excretion)
Factors that may affect outcome of CKD
Late referral HYPERTENSION PROTEINURIA high protein intake poor bone health Acidosis Recurrent UTIs
