Mycophenolate mofetil treatment of an H syndrome patient with a SLC29A3 mutation

Dermatol Ther. 2020 Nov;33(6):e14375. doi: 10.1111/dth.14375. Epub 2020 Oct 26.


H syndrome is a complex multi-organ disorder with autosomal recessive inheritance. The skin manifestations include early onset hyperpigmentation and hypertrichosis, followed by skin induration often diagnosed as scleromyxedema and morphea. There is no effective treatment. Our objective was to study the efficacy of mycophenolate mofetil in a patient with genetically confirmed H syndrome. We sought the genetic cause of H syndrome with whole-exome sequencing (WES) of the proband. Genome-wide homozygosity mapping (HM) provided additional evidence for causality of the variant suggested by WES. Here, we report a patient with characteristic clinical features of H syndrome, and the diagnosis was confirmed by identification of a homozygous SLC29A3 mutation (p.Gly437Arg). The patient was initially treated with prednisolone and cyclosporine, but after development of side-effects she was placed on mycophenolate mofetil. After the treatment with mycophenolate mofetil was initiated, resolution of hyperpigmentation was noted, and no new lesions developed during an 18-month follow-up period. Thus, mycophenolate mofetil could be considered as a safe and partially effective treatment of H syndrome.

Keywords: H syndrome; SLC29A3; genodermatosis; mycophenolate mofetil; next generation sequencing.

Publication types

  • Case Reports

MeSH terms

  • Female
  • Hearing Loss, Sensorineural*
  • Histiocytosis*
  • Humans
  • Immunosuppressive Agents / adverse effects
  • Mutation
  • Mycophenolic Acid / therapeutic use
  • Nucleoside Transport Proteins / genetics


  • Immunosuppressive Agents
  • Nucleoside Transport Proteins
  • SLC29A3 protein, human
  • Mycophenolic Acid