Supplementary Material for: Treatment of Hereditary Leukonychia with Intramatricial Triamcinolone: Case Report

Introduction:
Hereditary leukonychia is a rare genetic nail disorder characterized by whitening of the nail plate, which is sometimes due to mutations in the phospholipase C delta-1 (PLCδ1) gene. While leukonychia is typically asymptomatic, it carries significant psychosocial burden, and patients often report that others comment that they look like they are wearing nail polish. There are no known treatment options.

Case Presentation:
A 39-year-old Kuwaiti male with autosomal recessive variant of PLCδ1-related non-syndromic leukonychia affecting nine fingernails presented for treatment because he was socially stigmatized. Treatment with 30% glycolic acid chemical peel was ineffective. Because there is evidence suggesting a link between PLCδ1-related hereditary leukonychia and abnormal keratinization, we hypothesized that intralesional steroids, which inhibit keratinocyte activity and reduce inflammation within the nail matrix, may be an effective treatment. Following treatment with intramatricial triamcinolone, the patient experienced complete resolution of leukonychia in five fingernails and partial improvement in the remaining four.

Conclusion:
We present a case of successful treatment of hereditary leukonychia due to a phospholipase C δ-1 gene mutation with intramatricial triamcinolone. This case highlights the potential of this treatment approach for leukonychia and warrants further investigation in larger cohort studies.

引言：遗传性白甲病（hereditary leukonychia）是一类罕见的遗传性甲部疾病，以甲板发白为核心临床特征，部分病例由磷脂酶Cδ1（phospholipase C delta-1, PLCδ1）基因突变诱发。该病症通常无明显临床症状，但会给患者带来显著心理社会负担，不少患者表示他人常会误以为其涂抹了指甲油。目前尚无公认的有效治疗方案。

病例报告：1例39岁科威特男性患者，罹患常染色体隐性遗传型PLCδ1相关性非综合征性遗传性白甲病，累及9个手指甲，因遭受社会歧视前来就诊。予30%乙醇酸化学剥脱治疗，未见明显疗效。鉴于已有研究提示PLCδ1相关性遗传性白甲病与角质形成异常存在关联，我们推测可通过抑制角质形成细胞活性、减轻甲母质炎症的皮损内注射糖皮质激素，实现有效治疗。予甲母质内曲安奈德治疗后，患者5个手指甲的白甲病损完全消退，剩余4个手指甲的症状得到部分改善。

结论：本文报告1例由磷脂酶Cδ1基因突变所致的遗传性白甲病，经甲母质内曲安奈德治疗后获得成功缓解。本案例凸显了该治疗方案用于白甲病的潜在应用价值，有待开展更大规模的队列研究以进一步验证其疗效与安全性。