.jpg) # Café-au-lait Macules (카페오레반점) --- ## 1. Definition - **Café-au-lait macules (CALMs, 카페오레반점)** are **well-circumscribed, flat, hyperpigmented patches** with a light- to dark-brown color resembling “coffee with milk.” - Caused by increased melanin within basal keratinocytes. - **Not raised, not scaly**, and usually present at birth or early childhood. --- ## 2. Pathophysiology - **Cellular basis**: - Increased melanin in keratinocytes. - Number of melanocytes may be normal or slightly increased. - Melanosomes are larger and more numerous. - **Molecular drivers**: - Sporadic lesions: usually isolated, non-syndromic. - Syndromic lesions: linked to **NF1 gene mutation** (neurofibromin, tumor suppressor). - **Histology**: - Basal layer with increased melanin pigmentation. - Normal epidermal architecture, no atypia. --- ## 3. Clinical Features - **Appearance**: - Oval, uniform, tan-to-brown macules. - Borders: smooth (“coast of California”) in NF1; irregular (“coast of Maine”) in McCune–Albright syndrome. - **Size**: usually >0.5 cm in children, >1.5 cm in adults for diagnostic significance. - **Distribution**: commonly on trunk, buttocks, extremities. - **Persistence**: lifelong, do not fade with age. --- ## 4. Epidemiology & Prevalence - Isolated CALM: common in general population (10–20%). - Multiple CALMs: uncommon, strongly associated with genetic syndromes. - Present at birth or early childhood; number may increase with age. --- ## 5. Clinical Significance ### A. Isolated CALM - Benign, no systemic risk. - Often solitary or <3 lesions. ### B. Multiple CALMs - **Neurofibromatosis type 1 (NF1, 신경섬유종증 1형)**: - Diagnostic criterion: ≥6 CALMs >0.5 cm in children or >1.5 cm in adults. - Often accompanied by axillary/inguinal freckling and neurofibromas. - **McCune–Albright syndrome (맥쿤-올브라이트 증후군)**: - Large, irregular “coast of Maine” CALMs, endocrine abnormalities, fibrous dysplasia of bone. - **Other associations**: - Legius syndrome, Noonan syndrome with lentigines, Watson syndrome. --- ## 6. Differential Diagnosis - Post-inflammatory hyperpigmentation (PIH, 염증후 과색소침착). - Lentigines (렌티고). - Congenital melanocytic nevus (선천성 모반). - Becker’s nevus (베커 모반) — has hypertrichosis. --- ## 7. Management - **Isolated lesions**: reassurance; benign, cosmetic only. - **Multiple lesions**: investigate for syndromic associations (NF1, McCune–Albright, etc). - **Treatment (cosmetic)**: - Q-switched pigment lasers (Nd:YAG 532/1064 nm, Alexandrite, Ruby). - Results variable; recurrence common. - Strict photoprotection reduces recurrence. --- ## 8. Prognosis - Isolated CALMs: excellent prognosis. - Syndromic CALMs: prognosis depends on associated systemic disease (e.g., NF1 complications). --- ## 9. Clinical Pearls 1. **One café-au-lait spot = normal. Six or more = think NF1.** 2. Border morphology is a diagnostic clue: “coast of California” (smooth, NF1) vs. “coast of Maine” (jagged, McCune–Albright). 3. Histology shows only **increased basal melanin** — not a nevus, not a melanocytic proliferation. 4. Cosmetic laser treatment has **high recurrence rates**; patient counseling is crucial. --- ✅ **Summary for a doctor**: Café-au-lait macules (카페오레반점) are benign pigmented macules due to increased basal melanin. While isolated CALMs are common and harmless, multiple CALMs are a hallmark of systemic disorders, especially **Neurofibromatosis type 1**. Differentiation from other pigmented lesions is essential. Management is cosmetic, with lasers offering partial benefit but high recurrence. ---