Kidney Biopsy

Pediatric Kidney Biopsy

Overview

Kidney biopsy in pediatric patients is a crucial diagnostic procedure that involves obtaining kidney tissue samples for microscopic examination. This procedure is essential for diagnosing specific kidney diseases, determining the severity of kidney damage, and guiding treatment decisions.

Key Points

Gold standard for diagnosing many kidney diseases
Usually performed under ultrasound guidance
Requires careful patient selection and preparation
Success rates >95% in experienced centers
Essential tool for treatment planning and prognosis determination

Common Indications

Nephrotic syndrome
- Steroid-resistant cases
- Steroid-dependent cases with atypical features
- Frequent relapsers
Persistent proteinuria
- Protein/creatinine ratio >2.0
- Unexplained persistent proteinuria
Systemic diseases with kidney involvement
- Systemic lupus erythematosus
- Henoch-Schönlein purpura
- Systemic vasculitis
Unexplained acute kidney injury
Chronic kidney disease of unknown etiology

Absolute Contraindications

Uncontrolled bleeding disorders
Severe thrombocytopenia (<50,000/μL)
Uncontrolled hypertension
Single functioning kidney (relative)
Active kidney infection

Relative Contraindications

Small kidney size (<9 cm in length)
Multiple cysts
Anatomical abnormalities
Hydronephrosis

Pre-procedure Preparation

Laboratory Tests
- Complete blood count
- Coagulation profile
- Kidney function tests
- Blood type and cross-match
Imaging
- Ultrasound of kidneys
- Assessment of kidney size and structure
Medication Review
- Discontinue anticoagulants
- Hold NSAIDs for 5-7 days

Procedure Steps

Patient positioning in prone position with pillow under abdomen
Ultrasound marking of biopsy site
Local anesthesia administration
Real-time ultrasound guidance
Core needle biopsy (usually 16G or 18G)
Multiple passes (2-3) to obtain adequate tissue
Immediate specimen evaluation for adequacy

Major Complications

Severe bleeding requiring transfusion (1-2%)
Perirenal hematoma
Arteriovenous fistula
Adjacent organ injury

Minor Complications

Microscopic hematuria (common)
Transient gross hematuria
Local pain
Vasovagal reactions

Post-Procedure Monitoring

Bed rest for 4-6 hours
Vital signs monitoring
- Every 15 minutes for first hour
- Every 30 minutes for next 2 hours
- Hourly for next 4 hours
Urine monitoring for hematuria
Post-procedure ultrasound if indicated

Discharge Criteria

Stable vital signs
No significant hematuria
Adequate pain control
No signs of complications

Follow-up Instructions

Avoid strenuous activity for 1-2 weeks
Monitor for complications
Follow-up appointment in 1 week
Contact information for emergencies