Vitiligo (leukoderma)

Japanese: 白斑 - はくはん（英語表記）leukoderma; vitiligo

It is a white skin lesion with a clear border and no three-dimensional change, caused by lack of pigment production, depigmentation, or local anemia. The most common disease in which vitiligo is the only lesion is vitiligo vulgaris, commonly known as white catfish. There are two types of this disease: one in which the lesion is localized unilaterally in a certain nerve distribution area, and one in which white spots of various sizes occur in no particular location on the contralateral side. The most likely causes of the former are autonomic nervous system disorders, and the latter are autoimmune. The shapes of the vitiligo vary, and hair often turns gray in the vitiligo area. In extremely rare cases, redness and itching are observed in the affected area.

Vitiligo
facula

A bright spot on the surface of the Sun that can be seen with the naked eye. It can be seen relatively clearly in the slightly darker parts of the outer rim, and is often found around sunspots. The white spots appear brighter because they are several hundred degrees warmer than the rest of the Sun. However, when observed closely with a telescope, it can be seen that the surface of the Sun itself does not glow uniformly, but is covered with small white granular spots that are repeatedly created and destroyed with a life span of just a few minutes. White spots are areas where many of these white particles gather together.

Source: Encyclopaedia Britannica Concise Encyclopedia About Encyclopaedia Britannica Concise Encyclopedia Information

Japanese:

立体的変化を欠き，境界鮮明な白色の皮膚病変で，色素の産生を欠くとか色素脱失，または局所性貧血に起因する。白斑を唯一の病変とする疾患で最もしばしばみられるものが，俗に白なまずといわれる尋常性白斑である。本症は，一定の神経支配領域に限局して片側性に生じる型と，大小種々の白斑が特に部位を定めずに対側性に多発する型とがある。原因として前者は自律神経障害説，後者は自己免疫説が有力視されている。白斑の形状は種々で，白斑部では毛髪もしばしば白毛化する。きわめてまれに，病変部に一致して発赤やかゆみが認められる。

白斑
はくはん
facula

肉眼で見て，太陽表面の特に光の強い部分。周縁のやや暗い部分で比較的はっきり観測され，黒点の周囲にみられることが多い。白斑の部分は，ほかより温度が数百度程度高いためにより輝いて見えるが，望遠鏡で細かく観測すると，太陽面そのものが一様な輝きではなく，小さな白い粒状の斑点におおわれ，それが数分の寿命で生成消滅を繰返している。白斑はその白粒の多く集った部分である。

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