Infantile Systemic Hyalinosis Presenting as Pseudo-Paralysis in Infancy: Study of Six Cases

Vykuntaraju K Gowda1, Sahana M Srinivas2, Priya Gupta1

  • 1Department of Pediatric Neurology, Indira Gandhi Institute of Child Health, Bangalore, Karnataka, India.

PubMed

Insights

Infantile systemic hyalinosis, a rare genetic disorder caused by ANTXR2 gene mutations, presents with painful movements and skin lesions. Early diagnosis aids in avoiding unnecessary tests and enables prenatal diagnosis.

Area of Science:

  • Genetics
  • Pediatrics
  • Dermatology

Background:

  • Infantile systemic hyalinosis (ISH) is a rare, fatal genetic disorder.
  • It stems from mutations in the capillary morphogenesis gene-2 (CMG2)/Human anthrax toxin-2 (ANTXR2) gene.
  • Characterized by spindle cell proliferation and hyaline material deposition.

Purpose of the Study:

  • To report a series of infants diagnosed with ISH.
  • To highlight clinical presentations and diagnostic findings.
  • To emphasize the importance of genetic analysis for diagnosis and counseling.

Main Methods:

  • Retrospective chart review of infants diagnosed with ISH between January 2015 and December 2020.
  • Clinical data collection including symptoms, physical examination, and laboratory tests.
  • Skin biopsy and genetic studies (ANTXR2 gene sequencing).

Main Results:

  • The mean age of presentation was 9.4 months, with a 1:5 male to female ratio.
  • Common symptoms included painful limb movements, joint stiffness, gingival thickening, and skin lesions.
  • Skin biopsies showed hyalinized collagen, and genetic studies confirmed ANTXR2 pathogenic variants.

Conclusions:

  • ISH should be considered in infants with painful limb movements.
  • Diagnosis avoids unnecessary investigations and aids prognostication.
  • Genetic findings facilitate prenatal diagnosis for affected families.