Swensson O
Klinik für Dermatologie, Venerologie und Allergologie der Christian-Albrechts-Universität zu Kiel.
Hautarzt. 1999 Jul;50(7):483-90. doi: 10.1007/s001050050947.
Pachyonychia congenita (PC) comprises a heterogeneous group of autosomal dominantly inherited conditions showing characteristic nail thickening and associated signs such as palmoplantar keratoderma, follicular keratoses, and mucosal leukokeratoses. Less frequently epidermal cysts, hairshaft abnormalities, natal teeth and laryngeal involvement may be seen. Phenotypically and genetically two major forms of PC are recognized, pachyonychia congenita Jadassohn-Lewandowsky/PC type I (Medelian inheritance in man-MIM-167200) and pachyonychia congenita Jackson-Lawler/PC type II (MIM 167210). Both conditions show nail deformities, focal palmoplantar keratoderma, and follicular hyperkeratoses. Diagnostically relevant are leukokeratoses of the oral mucosa in patients with PC type I. In contrast individuals affected with PC type II show premature dentition and multiple pilosebaceous cysts predominantly affecting the upper trunk. The latter closely resemble eruptive vellus hair cysts and steatocystoma multiplex. By mutational analysis keratin K6a and K16 gene mutations have been detected in patients with PC type I, and keratin K6b and K17 gene mutations have been shown to be the underlying genetic defect in patients with PC type II.
先天性厚甲症（PC）是一组常染色体显性遗传疾病，具有指甲增厚的特征，并伴有掌跖角化病、毛囊角化病和黏膜白斑等相关体征。较少见的表现包括表皮囊肿、毛干异常、 natal teeth（原文有误，可能是natal teeth应为natal teeth or natal teeth anomalies，指出生时即有的牙齿或牙齿异常）和喉部受累。从表型和基因角度可识别出PC的两种主要类型，即先天性厚甲症雅达松 - 莱万多夫斯基型/PC I型（人类孟德尔遗传-MIM-167200）和先天性厚甲症杰克逊 - 劳勒型/PC II型（MIM 167210）。两种类型均表现为指甲畸形、局限性掌跖角化病和毛囊角化过度。PC I型患者口腔黏膜白斑具有诊断相关性。相比之下，PC II型患者表现为出牙过早和多个皮脂腺囊肿，主要累及上半身。后者与发疹性毳毛囊肿和多发性皮脂囊肿极为相似。通过突变分析，在PC I型患者中检测到角蛋白K6a和K16基因突变，而角蛋白K6b和K17基因突变已被证明是PC II型患者的潜在遗传缺陷。
