Objectives Childhood osteoporosis is often a consequence of a chronic disease or its treatment. Lysinuric protein intolerance (LPI), a rare secondary cause of the osteoporosis, is an autosomal recessive disorder with clinical features ranging from minimal protein intolerance to severe multisystemic involvement. We report a case diagnosed to have LPI using a Next Generation Sequencing (NGS) panel and evaluate the utility of reverse phenotyping. Case presentation A fifteen-year-old-boy with an initial diagnosis of osteogenesis imperfecta, was referred due to a number of atypical findings accompanying to osteoporosis such as splenomegaly and bicytopenia. A NGS panel (TruSight One Sequencing Panel) was performed and a novel homozygous mutation of c.257G>A (p.Gly86Glu) in the SLC7A7 gene (NM_001126106.2), responsible for LPI, was detected. The diagnosis was confirmed via reverse phenotyping. Conclusions Reverse phenotyping using a multigene panel shortens the diagnostic process.

中文翻译：

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反向表型的效用：一例因儿童骨质疏松症而出现的赖氨酸尿蛋白不耐受病例

目标 儿童骨质疏松症通常是慢性疾病或其治疗的结果。赖氨酸尿蛋白不耐受 (LPI) 是一种罕见的骨质疏松症继发性病因，是一种常染色体隐性遗传疾病，临床特征范围从轻微的蛋白质不耐受到严重的多系统受累。我们报告了一个使用下一代测序 (NGS) 面板诊断出患有 LPI 的病例，并评估了反向表型分析的效用。病例介绍 一名最初诊断为成骨不全症的 15 岁男孩因与骨质疏松症相关的许多非典型表现（如脾肿大和双血细胞减少症）而被转诊。进行了 NGS 面板（TruSight One Sequencing Panel），并检测到负责 LPI 的 SLC7A7 基因 (NM_001126106.2) 中 c.257G>A (p.Gly86Glu) 的新型纯合突变。通过反向表型证实了诊断。结论 使用多基因面板进行反向表型分析缩短了诊断过程。