PEDIATRIC NEPHROLOGY😊

PEDIATRIC NEPHROLOGY

Hematuria in a child

• Schistocytes.

Hemolytic Uremic Syndrome (HUS)

• Endothelial injury triggers the other events in HUS leading to a triad of injuries.
• Microangiopathic Hemolytic Anemia.
• Thrombocytopenia.
• Acute kidney injury.

Types of HUS

• Classical (D+ HUS):
• Secondary to infection
• by Shiga toxin-producing E. coli or Shigella dysentery.

• Atypical (D- HUS):
• Excess activation or
• insufficient inhibition
• of alternative complement pathway.
• E.g.:
• Factor H deficiency or
• factor I deficiency or
• presence of Anti-factor HADb.
• Secondary to infection by Streptococcal infection or Malaria.

Treatment of HUS

• Plasmapheresis/Therapeutic plasma exchange.

• Eculizumab: Useful in cases of refractory atypical HUS.

KDIGO Staging of AKI

• KDIGO: Kidney Disease Improving Global Outcomes.

• Stage 1:
• 0.3 mg/dl increase or 1.5-1.9 times baseline.
• < 0.5 ml/kg/hr for 6-12 hrs.

• Stage 2:
• 2-2.9 times baseline.
• < 0.5 ml/kg/hr for >12 hrs.

• Stage 3:
• 1 criteria
• 3 times baseline (or)
• serum creatinine > 4 mg/dl (or)
• indication of Renal replacement therapy (or)
• eGFR < 35 ml/min/1.73m².
• < 0.3 ml/kg/ml for > 24 hrs (or)
• Anuria for >12 hrs.

CKD - KDIGO Guidelines

Stage	GFR (ml/min/1.73 m²)	Notes
Stage 1	>90	Reversible
Stage 2	60 to 89	Reversible
Stage 3a	45 to 59	Treat complications
Stage 3b	30 to 44	Treat complications
Stage 4	15 to 29	Prepare for Renal Replacement
Stage 5	< 15 (ESRD)	Renal Replacement Therapy

Drugs Safe in AKI

• Paracetamol

• Warfarin

• Statins

• Aspirin

• B-blockers

• Clopidogrel

 

What is the appropriate next course of action in the management of a neonate who has not voided urine since birth and is now 1 day old?
A. Continue breast feeding not observed
B. Admit to NICU’
C. Start artificial feeding
D. Start intravenous fluids

Bedside assessment of GFR

Schwartz formula:

• Unit: ml/min/1.73 m2

• eGFR= (k x Ht (cm)) / Serum creatinine (mg/dl)
• where k=0.413 in children.

Pelviureteric Junction Obstruction (PUJO)

• MC cause of hydronephrosis in children is PUJO.

Posterior Urethral Valves (PUVV)

• Mc cause of obstructive uropathy in boys is PUV.

• Diagnosed by:
• Strain during urination.
• Improper urinary stream.
• Palpable urinary bladder.

• MC cause of renal scarring in children is Reflux induced nephropathy.

Urinary Tract Infection (UTI)

Recommended Imaging in Children with UTI

• Age <5 years
• USG KUB.
• If Abnormal → DMSA Scan.
• If Abnormal → Voiding Cysto-Urethrogram (VCUG).

Significance

• UTI is an important cause of fever without focus, especially in infants.

• <5 years: Must investigate for:
• Renal scarring
• Urinary tract anomalies

Classification

• Simple UTI
• Low-grade fever,
• dysuria,
• increased frequency

• Complicated UTI
• High-grade fever (>39°C)
• Systemic toxicity
• Renal angle tenderness
• ↑ Serum creatinine

• Recurrent UTI
• ≥ 2 episodes
• Investigate for anomalies

Etiology

• Most common cause of UTI in children
• E-coli > Klebsiella & Proteus.

• Bowel and bladder dysfunction is associated with UTI infection

Definitions

• Significant Bacteriuria (based on collection method & CFU/mL):
• Suprapubic aspiration: >10³ CFU/mL (99% probability)
• Urethral catheterization: >10⁴ CFU/mL (95%)
• Midstream clean catch: >10⁵ CFU/mL (90–95%)

• Asymptomatic Bacteriuria
• Significant bacteriuria without symptoms
• No treatment required

• Leukocyturia
• 10 WBC/mm³ in uncentrifuged urine
• 5 WBC/HPF in centrifuged sample
• Not diagnostic of UTI

Management

Hospitalization Indications

• Complicated UTI

• Infants <3 months

Antibiotic Therapy

• Simple UTI:
• Duration: 7–10 days
• Drugs: Co-amoxiclav, Cefixime

• Complicated UTI:
• Duration:
• 10–14 days
• Drugs:
• Ceftriaxone,
• Cefotaxime,
• Aminoglycosides
  (Amikacin/Gentamicin – single daily dose)

Investigations: First Episode

• USG KUB
• Check for anomalies and post-void residual
• If normal:
• No further imaging
• If abnormal or recurrent UTI or non-E. coli UTI:
• VCUG (voiding cystourethrogram) = MCU

• Micturating Cystourethrogram (MCU)
• Performed 2–4 weeks post-treatment
• Indications:
• Recurrent UTI
• Abnormal USG
• Detects VUR, PUV

• DMSA Scan
• Done 4–6 months post-treatment
• Detects renal scars
• Helps differentiate scarring from acute inflammation

Contrast X-rays

Dye studies for urethra	Route
IVP	Intravenous Pyelogram • via IV • Urethra is not seen
RGP	Retrograde Pyelogram • from down upwards • No bladder distension • view Ureter/Renal Pelvis
RGU	Retrograde Urethrogram • Preferred for anterior urethra evaluation for strictures. • e.g., urethral strictures, urethral injury/rupture.
MCU / VCUG	Micturating Cystourethrogram / Voiding cystourethrogram • 300ml contrast via foleys cannulation • Distend the bladder with contrast • IOC for 1. VUR 2. PUV

Computed Topography (CT) Scans

CT Scans	Identify	ㅤ
CT-IVU or CT-IVP.	KUB + White bone	Colourful imaging can be produced from urine.
T2 Magnetic Resonance (MR).	KUB NO White bone	Advantages 1. without contrast → Urine appears white 2. Safe in renal failure

Potter Syndrome/Sequence

Potters syndrome:

• Severe oligohydramnios due to kidney defects
• Renal agenesis
• B/L renal agenesis (incompatible with life).
• PCKD

• C/f:
• Lung hypoplasia
• most common cause of mortality in Potter syndrome
• Typical flat facies
• Potters sequence
• Severe oligohydramnios due to non renal causes

Clinical features:

• Extremities anomaly.
• Wrinkled skin.
• Facial dysmorphism.
• Renal agenesis B/L (primary anomaly).
• Oligohydramnios.
• Eyes widely separated.
• Epicanthic folds.
• Flat facies.
• High forehead.
• Receding chin.
• Washer man's hand.
• Potter facies.
 

 

Nephrotic Syndrome

• MC cause of Nephrotic syndrome in children is Minimal change disease.
• Kidney biopsy: Normal on light microscopy and flattened footplate of podocytes on electron microscopy.

• Nephrotic range/massive proteinuria (Up : Uc ratio > 2).

• Generalized edema.

• Hypoalbuminemia.

• Hyperlipidemia.

Treatment

• Drug of choice: Prednisolone 2mg/kg/day daily for 6 weeks followed by 1.5 mg/kg/day every alternate day for the next 6 weeks.
• 80%-90% of children respond within 2-3 weeks.

• Treat each relapse.

• Prednisolone 2mg/kg/day till remission or 60 mg/m²/day daily till remission followed by 4 weeks of alternate day steroids (1.5 mg/kg).

• FRNS (or) SDNS:

• Steroid threshold >0.5 mg/kg alternate day (or) features of steroid Toxicity:
• Levamisole.
• Oral Cyclophosphamide.
• Mycophenolate Mofetil.
• Drug of choice: Calcineurin inhibitors (Cyclosporine/Tacrolimus).

• Refractory cases:
• Rituximab (Anti CD20 Ab).

Nephritic Syndrome

• The most common cause of nephritic syndrome in children— PSGN (Post streptococcal Glomerulonephritis).

Definition

• Gross hematuria — Cola-colored urine.

• Proteinuria — Nephritic range (Up: Uc:- 0.2-2).

• Sudden onset of edema.

• With or without renal dysfunction.

Investigations in PSGN (Post streptococcal Glomerulonephritis)

Diagnosis

• Urine examination - Proteinuria, RBC, RBC casts, and Active sediments.
• C3 level decreased in 90% of patients, but normalized in 6-8 weeks of onset.

• Increased ASO (Anti Streptolysin O) titer following pharyngitis.

• Increased Anti DNASe B following pyoderma.