Osteomyelitis in Children
Pediatric Osteomyelitis
Definition
Osteomyelitis is an infection of bone that primarily affects the metaphysis of long bones in children. It can be caused by hematogenous spread, direct inoculation, or contiguous spread from adjacent soft tissue infection.
Epidemiology
- Age Distribution:
- Most common in children < 5 years
- Peak incidence: 2-3 years
- Male:Female ratio = 2:1
- Risk Factors:
- Recent trauma
- Immunocompromised state
- Sickle cell disease
- Indwelling catheters
- Sepsis
Classification
By Duration
- Acute: < 2 weeks
- Subacute: 2 weeks to 3 months
- Chronic: > 3 months
By Mechanism
- Hematogenous (most common in children)
- Contiguous spread
- Direct inoculation
By Waldvogel Classification
- Hematogenous
- Contiguous focus with vascular insufficiency
- Contiguous focus without vascular insufficiency
By Cierny-Mader Classification
- Anatomical Type:
- Stage 1: Medullary
- Stage 2: Superficial
- Stage 3: Localized
- Stage 4: Diffuse
- Host Status:
- Type A: Normal host
- Type B: Compromised host
- Type C: Treatment worse than disease
Pathophysiology
Microbiology
- Common Organisms:
- Staphylococcus aureus (80-90%)
- Group A Streptococcus
- Kingella kingae (< 4 years)
- Salmonella (Sickle cell disease)
- Age-Specific Considerations:
- Neonates: Group B Strep, E. coli
- Toddlers: Kingella kingae
- School-age: S. aureus
Anatomical Considerations
- Metaphyseal Location:
- Rich blood supply
- Slow blood flow in sinusoids
- Thin endothelial walls
- Common Sites:
- Femur (27%)
- Tibia (22%)
- Humerus (12%)
- Pelvis (7%)
Disease Progression
- Initial Phase:
- Vascular congestion
- Inflammatory response
- Increased intraosseous pressure
- Development:
- Pus formation
- Cortical perforation
- Subperiosteal abscess
Clinical Presentation
Symptoms
- General:
- Fever
- Irritability
- Lethargy
- Decreased appetite
- Local:
- Pain
- Tenderness
- Warmth
- Swelling
- Limited range of motion
- Pseudo-paralysis
Age-Specific Presentations
- Neonates:
- Subtle presentation
- Irritability
- Poor feeding
- Pseudo-paralysis
- Older Children:
- More localized symptoms
- Better able to communicate pain
- May have antecedent trauma
Diagnostic Approach
Laboratory Studies
- Blood Work:
- Complete blood count
- ESR (>20 mm/hr)
- CRP (>20 mg/L)
- Blood cultures (40-50% positive)
- Aspirate Studies:
- Gram stain
- Culture and sensitivity
- PCR for specific organisms
Imaging Studies
- Plain Radiographs:
- First line imaging
- Normal early in disease
- Changes visible after 7-14 days
- MRI:
- Gold standard
- Early changes visible
- Defines extent of infection
- Identifies abscess
- CT Scan:
- Better bony detail
- Surgical planning
- Nuclear Studies:
- Bone scan for multifocal disease
- Gallium scan
Treatment Approach
Initial Management
- Stabilization:
- Pain control
- Immobilization
- Supportive care
- Empiric Antibiotics:
- Coverage for MSSA/MRSA
- Age-appropriate coverage
- Consider local resistance patterns
Antibiotic Therapy
- Initial IV Therapy:
- Duration: 5-7 days minimum
- Choice based on local guidelines
- Common regimens:
- Clindamycin
- Vancomycin
- Nafcillin/Oxacillin
- Transition to Oral:
- After clinical improvement
- Total duration: 3-6 weeks
- Based on clinical response
Surgical Management
- Indications:
- Abscess formation
- Failed medical management
- Diagnostic uncertainty
- Procedures:
- Aspiration
- Decompression
- Debridement
- Drainage
Complications and Prognosis
Acute Complications
- Local:
- Septic arthritis
- Growth arrest
- Pathological fracture
- Deep vein thrombosis
- Systemic:
- Sepsis
- Multi-organ dysfunction
Chronic Complications
- Chronic osteomyelitis
- Growth disturbance
- Angular deformity
- Limb length discrepancy
- Chronic pain
Prognostic Factors
- Good Prognosis:
- Early diagnosis
- Appropriate antibiotics
- Good host response
- Single focus
- Poor Prognosis:
- Delayed treatment
- Resistant organisms
- Immunocompromised host
- Multifocal disease
Disclaimer
The notes provided on Pediatime are generated from online resources and AI sources and have been carefully checked for accuracy. However, these notes are not intended to replace standard textbooks. They are designed to serve as a quick review and revision tool for medical students and professionals, and to aid in theory exam preparation. For comprehensive learning, please refer to recommended textbooks and guidelines.
