What is a café-au-lait macule?
A café-au-lait macule (abbreviated CALM) is a light-brown pigmented flat patch on the skin; the name means literally “coffee-with-milk spot”. It is a fairly common and benign pigment mark.
What does it look like?
A café-au-lait macule has a characteristic, evenly light-brown colour and can vary in size from one to several centimetres. The border with the normal skin is sharp.
How does it develop?
The mechanism by which a café-au-lait macule develops is not entirely clear. The density of pigment-forming cells (melanocytes) in the skin is normal, but the cells produce an abnormal pigment.
Who gets café-au-lait macules?
They are usually seen immediately after birth, or arise in the first months of life. Usually there are only one or a few, but sometimes there is a large number. When there is a larger number (more than six), there may be neurofibromatosis. Neurofibromatosis is a genetic condition that, besides various skin complaints, can also be accompanied by neurological and eye problems.
How are they treated?
Because a café-au-lait macule is benign it does not in principle need to be treated. If it presents a cosmetic drawback, treatment with the pigment laser is possible, but the results are variable: the macule disappears completely in only a minority of cases, and in some the spot can even become darker after laser treatment. It is therefore important to have a test spot treated first, before treating the whole area, to assess the effects.
When to see a doctor
See your GP if a child has several café-au-lait spots (six or more), especially if larger than about half a centimetre, so that they can be checked and, if needed, followed up for neurofibromatosis. A single café-au-lait macule is harmless, but any pigment mark that becomes irregular, changes or has an unusual colour is worth having assessed.