Hyperpigmented Lesions in Pediatric Dermatology

Hyperpigmented lesions represent a diverse group of skin conditions characterized by increased melanin deposition or other pigments in the skin, resulting in darkened patches or spots.

Key Points

• Common presentation in all skin types, but more noticeable in lighter skin
• Can be congenital or acquired
• May indicate underlying systemic conditions
• Pattern recognition crucial for accurate diagnosis

Etiology

Common Causes

• Post-inflammatory hyperpigmentation (PIH)
• Café-au-lait macules
• Mongolian spots (dermal melanocytosis)
• Lentigines
• Melasma

Pathophysiology

• Increased melanin production
• Abnormal melanin distribution
• Dermal melanin deposition
• Increased number of melanocytes

Risk Factors

• Genetic predisposition
• Sun exposure
• Trauma or inflammation
• Hormonal changes
• Certain medications

Clinical Features

Common Presentations

• Café-au-lait Macules:
  • Light brown, well-defined patches
  • Oval or irregular shape
  • Present at birth or early childhood
  • Multiple lesions may indicate neurofibromatosis
• Mongolian Spots:
  • Blue-gray patches
  • Common in sacral region
  • Present at birth
  • Usually fade by school age
• Post-inflammatory Hyperpigmentation:
  • Dark patches in areas of previous inflammation
  • Variable shapes and sizes
  • May be temporary or permanent

Associated Symptoms

• Usually asymptomatic
• May cause psychological distress
• Can be associated with systemic symptoms in syndromic cases

Diagnosis

Clinical Assessment

• Detailed history:
  • Age of onset
  • Evolution of lesions
  • Family history
  • Associated symptoms
• Physical examination:
  • Distribution pattern
  • Color and texture
  • Associated findings

Diagnostic Tools

• Wood's lamp examination
• Dermoscopy
• Skin biopsy (when indicated)
• Genetic testing (for suspected syndromes)

Differential Diagnosis

• Nevus of Ota
• Becker's nevus
• Fixed drug eruption
• Acanthosis nigricans
• Tinea versicolor

Management

Treatment Approaches

• Preventive Measures:
  • Sun protection
  • Avoiding trauma
  • Treatment of underlying conditions
• Topical Treatments:
  • Hydroquinone (with caution in children)
  • Kojic acid
  • Azelaic acid
  • Vitamin C derivatives
  • Retinoids
• Procedural Treatments:
  • Chemical peels
  • Laser therapy
  • Intense pulsed light

Monitoring and Follow-up

• Regular assessment of lesion progression
• Photography for documentation
• Screening for associated conditions
• Psychological support when needed