Goldberg I, Mashiah J, Kutz A, Derowe A, Warshauer E, Schwartz M E, Smith F, Sprecher E, Hansen C D
Department ofDermatology, Tel Aviv University, Tel Aviv, Israel.
Department ofOtolaryngology, Head and Neck and Maxillofacial Surgery, Tel-Aviv Sourasky Medical Center, affiliated to Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.
Br J Dermatol. 2020 Mar;182(3):708-713. doi: 10.1111/bjd.18742. Epub 2019 Dec 25.
Pachyonychia congenita (PC) is a rare autosomal dominant genodermatosis caused by a mutation in any one of five keratin genes (KRT6A, KRT6B, KRT6C, KRT16 or KRT17). Characteristic features of PC are painful palmoplantar keratoderma, variable nail dystrophy, cysts, follicular hyperkeratosis and often oral leukokeratosis. Although oral leukokeratosis can go unnoticed, mucosal involvement of the oral cavity and upper airways can manifest with pain during feeding, hoarseness, stridor and, occasionally, life-threatening obstruction.
To characterize patients with PC with symptomatic mucosal involvement.
We present a case series of nine children with PC with symptomatic mucosal involvement, all with heterozygous mutations in KRT6A. Seven patients complained of painful feeding problems. Four patients were diagnosed with failure to thrive, three of whom required a feeding tube. Simple feeding solutions were beneficial in most cases. Seven patients had laryngeal involvement and one patient died at 4 years of age from acute laryngeal obstruction.
It is important for dermatologists and otolaryngologists to be aware that symptomatic mucosal involvement, and very rarely laryngeal obstruction, can occur in patients with PC. Usually simple feeding solutions may prevent complications and failure to thrive. What's already known about this topic? Pachyonychia congenita (PC) is a rare autosomal dominant genodermatosis due to a mutation in any one of five keratin genes. Symptomatic mucosal involvement is an important clinical feature of PC and appears to be more pronounced in KRT6A mutation carriers. Only leukokeratosis is frequently seen in PC and can be one of the earliest signs of disease. Laryngeal involvement is a less common feature. It might be symptomatic but usually presents as hoarseness, stridor and, occasionally, as a life-threatening respiratory distress. What does this study add? In most cases of laryngeal involvement, there is no need for any intervention. Although pain and feeding difficulties are usually attributed to the oral leukokeratosis, they can be related to a phenomenon called 'first bite syndrome' (FBS). Symptomatic mucosal involvement with feeding difficulty is important but can be managed in most cases with simple feeding solutions (e.g. softer nipple with a larger hole, thicker formula and feeding with a syringe). Linked Comment: Youssefian and Vahidnezhad. Br J Dermatol 2020; 182:536-537.
先天性厚甲症（PC）是一种罕见的常染色体显性遗传性皮肤病，由五个角蛋白基因（KRT6A、KRT6B、KRT6C、KRT16或KRT17）中任何一个发生突变引起。PC的特征性表现为掌跖角化病伴疼痛、指甲营养不良程度不一、囊肿、毛囊角化过度，且常伴有口腔黏膜白斑病。尽管口腔黏膜白斑病可能未被注意到，但口腔和上呼吸道的黏膜受累在喂养时可表现为疼痛、声音嘶哑、喘鸣，偶尔还会出现危及生命的梗阻。
对有症状性黏膜受累的PC患者进行特征描述。
我们报告了一组9例有症状性黏膜受累的PC患儿病例系列，均为KRT6A基因杂合突变。7例患儿主诉有喂养疼痛问题。有4例患儿被诊断为发育不良，其中3例需要鼻饲管喂养。大多数情况下，简单的喂养方案有益。7例患儿有喉部受累，1例患儿4岁时死于急性喉梗阻。
皮肤科医生和耳鼻喉科医生应认识到，PC患者可能出现有症状性黏膜受累，喉梗阻则非常罕见。通常，简单的喂养方案可预防并发症和发育不良。关于该主题已了解哪些内容？先天性厚甲症（PC）是一种罕见的常染色体显性遗传性皮肤病，由五个角蛋白基因中任何一个发生突变所致。有症状性黏膜受累是PC的一个重要临床特征，在KRT6A突变携带者中似乎更为明显。在PC中，仅黏膜白斑病较为常见，且可能是该病最早的体征之一。喉部受累是较不常见的特征。可能有症状，但通常表现为声音嘶哑、喘鸣，偶尔表现为危及生命的呼吸窘迫。本研究补充了哪些内容？在大多数喉部受累病例中，无需任何干预。尽管疼痛和喂养困难通常归因于口腔黏膜白斑病，但它们可能与一种称为“第一口综合征”（FBS）的现象有关。有症状性黏膜受累伴喂养困难很重要，但大多数情况下可通过简单的喂养方案（如使用孔较大的较软奶嘴、较稠的配方奶和用注射器喂养）进行处理。相关评论：Youssefian和Vahidnezhad。《英国皮肤病学杂志》2020年；182:536 - 537。
