Café-au-lait Spots

What is it?

Café-au-lait spots (also called café-au-lait macules or CALMs) are flat, pigmented birthmarks that appear as light to dark brown patches on the skin, resembling the color of coffee with milk—hence their French name. These well-defined patches result from increased melanin (skin pigment) and melanocytes (pigment-producing cells) in the affected area. While often present at birth or appearing during the first year of life, they may become more visible with age. A single café-au-lait spot is common and typically harmless, occurring in approximately 10% of the general population. However, multiple spots (six or more) may indicate an underlying genetic condition, particularly neurofibromatosis type 1 (NF1), making proper evaluation essential for children with numerous café-au-lait spots.

Who is affected?

Café-au-lait spots occur across all populations with notable demographic variations:

• General prevalence: Approximately 10% of people have at least one café-au-lait spot
• Newborn occurrence: Present in 0.3% of white infants to 18% of African American infants
• Childhood prevalence: Found in 25% of preschool-aged children
• Ethnic variations: More common and visible in individuals with darker skin tones
• Age of appearance: Often present at birth or emerging during the first year of life
• Multiple spots: Having 3 or more spots occurs in 1-14% of the population
• Syndromic association: Six or more spots meeting size criteria warrant evaluation for genetic syndromes

What causes it?

The pathophysiology involves complex melanocyte (pigment cell) regulation:

Isolated café-au-lait spots:

• Mechanism: Localized increase in melanin production and melanocyte number
• Genetics: Usually sporadic, not inherited
• Triggers: Unknown in most isolated cases
• Significance: Benign variation of normal pigmentation

Multiple café-au-lait spots - Associated syndromes:

• Neurofibromatosis Type 1 (NF1) - Most common association:

  • Genetic mutation affecting nerve tissue growth
  • 77% of children with ≥6 typical spots develop NF1
  • Associated with benign nerve tumors (neurofibromas)

• Legius syndrome:

  • Similar presentation to NF1 but without tumors
  • Caused by SPRED1 gene mutation

• McCune-Albright syndrome:

  • Classic triad: bone abnormalities, hormonal dysfunction, café-au-lait spots
  • Spots have characteristic jagged borders

• Constitutional mismatch repair deficiency (CMMRD):

  • Rare cancer predisposition syndrome
  • All patients have café-au-lait spots plus early cancers

• Noonan syndrome and RASopathies:

  • Heart defects, facial features, short stature with café-au-lait spots

What are the clinical features?

Café-au-lait spots present with characteristic appearance and distribution patterns:

Physical characteristics:

• Color: Light brown to dark brown ("coffee with milk" appearance)
• Shape: Well-circumscribed, evenly pigmented flat patches
• Size: Variable, ranging from 1-2 millimeters to over 20 centimeters
• Borders:
  • Smooth borders ("coast of California") in isolated spots or NF1
  • Jagged borders ("coast of Maine") in McCune-Albright syndrome
• Location: Can appear anywhere but commonly on trunk and extremities
• Texture: Smooth surface, same texture as surrounding skin

Diagnostic size criteria (for syndrome evaluation):

• Before puberty: Six or more spots measuring >5 millimeters
• After puberty: Six or more spots measuring >15 millimeters
• Wood's lamp examination: Ultraviolet light enhances visualization, particularly helpful in newborns or fair-skinned individuals

How is it diagnosed?

Diagnosis involves clinical assessment and potential genetic evaluation:

Clinical evaluation:

• Visual inspection: Count, measure size, assess border characteristics
• Wood's lamp examination: Enhances visibility under ultraviolet light
• Dermoscopy: Reveals reticular pigment pattern with follicular sparing
• Family history: Important for identifying hereditary syndromes

When to seek further evaluation:

• Six or more spots meeting age-appropriate size criteria
• Associated features: Freckling in armpits/groin, bumps on skin, learning difficulties
• Family history of neurofibromatosis or related conditions
• Atypical features: Jagged borders, unusual distribution

Genetic testing indications:

• Multiple café-au-lait spots without other diagnostic features
• Young children requiring early diagnosis
• Family planning considerations
• Distinguishing between similar syndromes (NF1 vs. Legius syndrome)

What treatment options are available?

Management depends on whether spots are isolated or syndrome-associated:

Isolated café-au-lait spots:

• No treatment necessary: Benign condition without health risks
• Cosmetic options (if desired):
  • Laser therapy: Most effective treatment for cosmetic improvement
    • Q-switched 1064-nm Nd:YAG laser shows best results
    • Picosecond lasers offer fewer side effects
    • Multiple sessions required (typically 12-24 treatments)
    • 50% clearance achieved in 75% of patients
  • Predictors of laser success:
    • Jagged or irregular borders respond better
    • Smooth-bordered spots show poorer response
  • Camouflage makeup: Non-invasive cosmetic coverage

Syndrome-associated spots:

• Primary focus: Managing underlying genetic condition
• Regular monitoring: Based on specific syndrome requirements
• Multidisciplinary care: Genetics, dermatology, neurology coordination
• Laser treatment: May be considered for cosmetic concerns after syndrome management

Key points for patients

• Single or few café-au-lait spots are common and harmless
• Six or more spots warrant medical evaluation for genetic syndromes
• Size criteria differ before and after puberty (5mm vs. 15mm)
• Most children with multiple spots meeting criteria develop NF1 by age 6
• Spots themselves have no malignant potential
• Laser treatment can improve appearance but requires multiple sessions with possible recurrence
• Regular monitoring is essential for syndrome-associated cases
• Genetic counseling helps families understand inheritance patterns and risks