Coffee Spots

Coffee spots

Café-au-lait spots, also known as cafe-au-lait spots, are light brown patches that can be found at birth. The color of coffee spots ranges from light brown to dark brown, but each piece is the same color and very uniform. The depth is not affected by sun exposure. The size ranges from a few millimeters to tens of centimeters, with clear boundaries and completely normal surface skin texture. Under a microscope, its appearance is very similar to that of freckles, mainly manifested by an abnormal increase in the amount of melanin in the epidermis. 

1.Cause and pathogenesis

Café-au-lait spots are mostly hereditary skin diseases and have nothing to do with sun exposure. They can be a sign of multi-system diseases, such as neurofibromatosis, Albright syndrome, Watson syndrome, Russell-Silver dwarfism, multiple lentigo syndrome and ataxia telangiectasia. Most coffee spots are not hereditary. However, it should be noted that if coffee spots occur in multiple parts and multiple areas (accumulated in more than three parts), this is a sign of neurofibroma. This type of coffee spots is highly hereditary.

2. Clinical manifestations

Café de café spots are light brown spots, ranging from brown to dark brown, of varying sizes, round, oval or irregular in shape, with clear borders and smooth surfaces. They may appear at birth or later and increase in number throughout childhood. They are more common on the trunk and will not disappear on their own. Some people believe that 90% of patients with neurofibromatosis have café de café spots. If there are 6 café de café spots with a true diameter greater than 1.5cm, the patient often has neurofibromatosis. Café de café spots that appear in different diseases may have different characteristics and be accompanied by other abnormal manifestations.

3. Pathological characteristics

During the pathological changes of café de café spots, epidermal melanin increases, especially in the basal layer. There are giant melanosomes in dopa-stained melanocytes and basal keratinocytes, and basal melanocytes are normal or slightly increased.

4. Diagnosis and differential diagnosis

According to the age of onset, milk coffee spots with clear edges can be diagnosed, and they need to be differentiated from freckles and simple freckles. Freckles mainly occur on the face, with small spots and no large flaky lesions. Simple freckles are mostly unilateral and can occur at any age.

5. Treatment

Previous traditional treatment methods such as ionization, cryotherapy, and CO2 laser often produce serious adverse reactions such as permanent pigment changes or scar formation, and have been eliminated clinically. At present, pulsed laser treatment is still the main treatment, but the effect after treatment is often unpredictable, the recurrence rate is high, and no laser can achieve ideal therapeutic effects. Laser treatment of coffee spots is similar to freckles. Lasers that are effective for melanin can be used to treat coffee spots. Treatment parameters and efficacy judgment are also the same as freckles.
(I) Pulsed dye (510nm) laser treatment
Energy density 2~3J/cm’, spot 5mm, no overlap between spots. The immediate reaction during treatment is that the tissue immediately changes to grayish white. The treatment cycle is generally 6~8 weeks apart, and 2~12 treatments are required. Pigmentation or hypopigmentation rarely occurs.
(II) Q-switched frequency-doubled Nd:YAG (532nm) laser treatment Energy density 2.0~2.5J/cm’, spot 1~3mm, pulse frequency 10Hz The treatment effect is unpredictable. (III) Q-switched ruby ​​laser
Wavelength 694nm, energy density 2~5J/cm’, spot 2~4mm, treatment cycle is generally 1~2 months apart and requires 4 or more treatments.
(IV) Q-switched alexandrite laser
Wavelength 755nm, energy density 6~7J/cm’, spot 2~4mm, treatment cycle and number of times are the same as ruby ​​laser. Domestic reports show that it has lower efficacy than Q-switched 694nm laser and relatively higher recurrence rate. (V) Quasi-continuous wave copper vapor laser (511nm) and laser (520~530nm)
The treatment parameters of copper vapor laser (511nm) are 0.16~0.25W, 150pm spot, interval time 0.2s, krypton laser is 700mW, 1mm spot, 0.2s pulse. Both lasers are effective in treating coffee spots, but usually cause skin texture changes or scars.
(VI) Intense Pulsed Light (IPL) Treatment
The energy density is 20~24J/cm2, and the number of treatments is 1~5 times. The intense pulsed light generated by IPL removes melanin in the basal layer and above more thoroughly. Yamnshita et al. found that the melanosomes in the basal layer of the epidermis after IPL treatment quickly migrated to the surface of the skin. However, coffee spots require multiple treatments to prevent nearby unirradiated melanocytes from re-pigmenting. After treatment, avoid light to reduce the activity of residual melanin. Generally speaking, if there is no recurrence within 6 months after the treatment is stopped, it means that the treatment effect of this type of patients is relatively good, and may even be completely cured in the end.

Source: Coffee Spots