Mongolian Spots

Mongolian spots are the macular bluish-gray pigmentation that affects the sacral area of infants. These spots are present from the time of birth. It can also develop in the first few weeks of infant life. Although Mongolian spots are said to disappear within 4 years, in extreme cases it may be present for a lifetime.

Mongolian spots is a congenital disorder involving only the skin. It is caused by the trapping of melanocytes in the skin. This happens when they travel from the neural crest to the epidermis.

The disorder is more common among Native Americans, Asians, and Hispanics. On the brighter side, Mongolian spots do not cause mortality or morbidity. More than 90% infants belonging to the Mongoloid race are affected. The disorder has no sexual preference. Mongolian spots occur at birth, but it can develop in the first few weeks of neonatal period.

The skin discoloration is because of the deep placement of the pigment in the skin. The Tyndall effect of scattered light is responsible for the bluish hue. The spots spread over a few centimeters in diameter. Lesions can be solitary or several in number. The lumbosacral area is the primary area to be affected. The buttocks, flanks, and shoulders are secondary areas. Severe forms of the disorder affect the entire trunk region.

Severe cases involve larger areas and sharper margins. These can persist for many years. Persistent aberrant Mongolian spots are also known as macular-type blue nevi. Superimposed Mongolian spots are also possible. In such cases, darker spots cover lighter ones.

The disease has an association with cleft lip, spinal meningeal tumor, and melanoma. In some cases, the spots may occur in combination with metabolic disorders, such as Hurler syndrome, Niemann-Pick disease, and mannosidosis. In such cases, the disease persists for longer periods of time. Mongolian spot is hereditary disorder.