Department of Rheumatology and Clinical Immunology, University Medical Center Freiburg, Freiburg, Germany.
Hum Immunol. 2010 Sep;71(9):916-9. doi: 10.1016/j.humimm.2010.06.002. Epub 2010 Jun 9.
Cartilage hair hypoplasia (CHH) is an autosomal recessive disorder caused by mutations in the ribonuclease mitochondrial RNA-processing (RMRP) gene. Although its most constant feature is metaphyseal dysplasia with short stature, CHH is associated with extraskeletal defects such as thin hair, anemia, immunodeficiency, and increased incidence of lymphomas. The spectrum of immunologic phenotypes in CHH translates into clinical severity. Whereas T-cell deficiency may remain subclinical or may result in severe combined immunodeficiency or Omenn syndrome, humoral immunodeficiency has only rarely been noted in these patients. Here we report the diagnosis of CHH in a woman who presented with severe short stature and a full-blown antibody deficiency, clinically resembling common variable immunodeficiency. Sequencing of the RMRP gene revealed compound heterozygosity for two novel mutations (g.68_69delinsTT and g.76C>T). Despite the late onset of immunodeficiency in the patient, its clinical course was severe, and the patient died 3 years after the first diagnosis.
软骨毛发发育不良症（CHH）是一种常染色体隐性遗传病，由核糖核酸内切酶线粒体 RNA 加工（RMRP）基因突变引起。虽然其最常见的特征是干骺端发育不良伴身材矮小，但 CHH 还与骨骼外缺陷有关，如毛发稀疏、贫血、免疫缺陷和淋巴瘤发病率增加。CHH 的免疫表型谱转化为临床严重程度。虽然 T 细胞缺陷可能处于亚临床状态，也可能导致严重联合免疫缺陷或 Omenn 综合征，但这些患者中很少注意到体液免疫缺陷。在这里，我们报告了一名女性 CHH 的诊断，她表现为严重的身材矮小和完全的抗体缺陷，临床上类似于常见的可变免疫缺陷。RMRP 基因突变的测序显示了两种新突变（g.68_69delinsTT 和 g.76C>T）的复合杂合性。尽管患者的免疫缺陷发病较晚，但病情严重，患者在首次诊断后 3 年内死亡。
