Severe dermatitis, multiple allergies and metabolic wasting (SAM) syndrome caused by de novo mutation in the DSP gene misdiagnosed as generalized pustular psoriasis and treatment of acitretin with gabapentin

J Dermatol. 2019 Jul;46(7):622-625. doi: 10.1111/1346-8138.14925. Epub 2019 May 20.

Abstract

Severe dermatitis, multiple allergies and metabolic wasting (SAM) syndrome is a recently recognized syndrome caused by mutations in the desmoglein 1 (DSG1) and desmoplakin (DSP) genes. Only two cases of SAM-DSP have been reported. We report on a 2-year-old girl presenting with pustular lakes within areas of erythema and large accumulations of intraepidermal neutrophils, which initially led to our misdiagnosis of generalized pustular psoriasis. No mutation was found in either the IL36RN or CARD14 genes by Sanger sequencing. The distinctive manifestations of erythroderma with severe itching, hypotrichosis, enamel defects, onychodystrophy, palmoplantar keratoderma and the crucial result of de novo missense mutation in exon 14 of the DSP gene (c.1828T>C, p.S610P) discovered by next-generation sequencing finally confirmed the diagnosis of SAM syndrome. The eruptions significantly improved after a 4-week treatment with oral acitretin and topical pimecrolimus. Oral gabapentin was prescribed simultaneously for 4 months, relieving her skin pruritus and suggesting that early treatment with pimecrolimus, acitretin and gabapentin for SAM-DSP syndrome is effective. It may even inhibit multiple allergies induced by skin barrier injury. In this work we also review the clinical features, differential diagnoses and pathological manifestations of SAM-DSP syndrome.

Keywords: DSP gene; hypotrichosis; palmoplantar keratoderma; pustular psoriasis; severe dermatitis, multiple allergies and metabolic wasting (SAM) syndrome.

Publication types

  • Case Reports

MeSH terms

  • Acitretin / administration & dosage*
  • Administration, Cutaneous
  • Administration, Oral
  • Child, Preschool
  • DNA Mutational Analysis
  • Dermatitis, Exfoliative / diagnosis*
  • Dermatitis, Exfoliative / drug therapy
  • Dermatitis, Exfoliative / genetics
  • Dermatitis, Exfoliative / pathology
  • Desmoplakins / genetics*
  • Diagnosis, Differential
  • Diagnostic Errors
  • Female
  • Gabapentin / administration & dosage*
  • Humans
  • Hypersensitivity / diagnosis*
  • Hypersensitivity / drug therapy
  • Hypersensitivity / genetics
  • Hypersensitivity / pathology
  • Mutation, Missense
  • Psoriasis / diagnosis
  • Severity of Illness Index
  • Skin / drug effects
  • Skin / pathology
  • Syndrome
  • Tacrolimus / administration & dosage
  • Tacrolimus / analogs & derivatives
  • Treatment Outcome
  • Wasting Syndrome / diagnosis*
  • Wasting Syndrome / drug therapy
  • Wasting Syndrome / genetics
  • Wasting Syndrome / pathology

Substances

  • DSP protein, human
  • Desmoplakins
  • Gabapentin
  • pimecrolimus
  • Acitretin
  • Tacrolimus