Congenital facial erythema is an extremely common lesion, commonly known as “red birthmark”, which is easy to distinguish and is diagnosed as “wine spot” or “bright red nevus”, which is essentially a It is essentially a congenital capillary or microvascular malformation. But is the diagnosis of erythema really that simple? Can you tell at a glance? In most cases it is, but we must realize that underneath the erythema, are there other lesions that gradually age and reveal their killer-like appearance? This erythema, which grows on the scalp, when touched will feel a higher than normal skin temperature and a slight pulse-like eruption in some areas, not unlike the usual erythema. The early “arteriovenous malformation” hidden under this erythema can be further clarified when imaging is performed, but it has not shown obvious symptoms yet. This case may also have intracranial lesions, which is equivalent to a “time bomb” and difficult to treat. The effective treatment of arteriovenous malformations is still an international challenge. In addition to the scalp, this erythema can be seen on other parts of the body, especially the face and neck. The disease progresses at different rates, sometimes slowly, and can remain stable into adulthood. This erythema, located around the eye, is nothing special, but in a few cases it may occur together with two other diseases, DD “chronic glaucoma” and “intracranial venous malformation”, which we call ” Sturge-Weber syndrome” (which will be described later in the topic “Vascular disease syndrome”). Glaucoma can lead to blindness in severe cases, but intracranial venous malformations can be treated without special treatment if they are asymptomatic. If the erythema involves the upper eyelids and forehead, the risk of this condition is relatively high. These erythema on the legs are probably a manifestation of “Klippel-Trenaunay”, where there may be extensive venous malformations deep in the skin, although they may not be apparent. As the limb grows, it may develop abnormally, with length discrepancies that can be severe enough to affect function. Early intervention will likely reduce the deformity later in life. Therefore, we can see that although the typical wine stain is easy to diagnose, we should never underestimate it and need to take care to examine the subtleties of each lesion and try to exclude other conditions that may be present. Physical examination and imaging will provide a strong diagnostic basis. In addition to this, there are other lesions that can exhibit erythema and require a specialist to better identify them. Therefore, if you have doubts about your condition, it is best to seek help from a medical professional.