Growth Hormone Response in a Child With a Homozygous TOMM7 Mutation: Novel Therapeutic Insights.

BACKGROUND Translocase of the outer mitochondrial membrane 7 (TOMM7) encodes a subunit of the mitochondrial translocase complex, which has a critical role in stabilizing the complex and regulating mitochondrial function. Rare individual case reports have identified homozygous TOMM7 mutations associated with Garg-Mishra progeroid syndrome (GMPGS), characterized by dwarfism, facial dysmorphia, developmental delay, and macular scarring. However, few therapeutic interventions have been documented. CASE REPORT We describe a 2-year-old Han boy from China with severe growth retardation who carries a homozygous TOMM7 mutation (p.Pro29Leu), inherited from consanguineous parents; he has a confirmed diagnosis of GMPGS. Because of growth stagnation, the child has been receiving long-acting recombinant human growth hormone since 31 months of age. After 10 months of treatment, his length increased by 3.8 cm (change in standard deviation score [SDS] of -0.34). This modest decline in SDS sharply contrasted with the precipitous drop of 1.28 SDS during the 10 months before treatment; it represented distinct improvement from the near-complete growth arrest observed between 24 and 31 months of age. CONCLUSIONS This case highlights the clinical characteristics of children with TOMM7 mutations and offers a potential strategy for managing growth retardation associated with mitochondrial dysfunction.