先天性無爪甲症の2例

TWO CASES OF ANONICHIA CONGENITA

I．はじめに

　無爪甲症とは爪甲の欠如した状態をいい，爪甲萎縮症とは爪甲が発育停止によつて萎縮している状態であり，このような変化は先天性奇型として出現する場合と後天性に出現する場合とがある。後天性の原因としては，爪甲自体の変化によるものと爪甲周囲の病変あるいは全身性疾患に続発するものがある。先天性無爪甲症とは生下時より既に全ての，あるいは殆どの爪甲が欠如しており，永久に正常な爪甲の新生をみず，原因と考えうる異常状態が併存しないという稀な疾患である。先天性無爪甲症と先天性爪甲萎縮症は合併している症例が多く，両者の区別は病状の程度によるものであり，本質的には同義とされている^1）。本症は時に遺伝性，家族性発生や他の奇型との合併がみられることは興味深い。

　本稿では昭和19年に谷奥が東大在職中に経験した本症症例と，最近著者らが経験した症例を合せて2例報告する。

Two cases of anonichia congenita were reported.

Case 1 was 5-month-old male who was born by a normal delivery. All nails of the hands and feet were absent at birth and the regeneration was not found. The distal phalanges were poorly developed. No other complications were observed. Histological findings of the nail bed showed the same keratinizing process as in the normal epidermis but the nail matrix was absent.

Case 2 was a 4-year-old female who was born by a forceps operation in asphyxia. Two of the right foot nails were deformed and the rest were absent. The distal phalanges of the feet were poorly developed. All the finger nails were normal. The complications of thromboasthenic purpura and suspected congenital heart disease were observed.

There were no family history of the same nail diseases and consanguinity in these two cases.