title: Early characteristic radiographic changes in mucolipidosis II.
abstract: BACKGROUND
  Although mucolipidosis type II has similar metabolic abnormalities to those found in all the mucopolysaccharidoses and mucolipidoses, there are distinctive diagnostic radiographic changes of mucolipidosis II in the perinatal/newborn/infant period.
  
  
  OBJECTIVE
  To describe the early characteristic radiographic changes of mucolipidosis II and to document when these changes manifest and resolve.
  
  
  METHODS
  We retrospectively reviewed radiographs and clinical records of 19 cases of mucolipidosis II from the International Skeletal Dysplasia Registry (1971-present; fetal age to 2½ years). A radiologist with special expertise in skeletal dysplasias evaluated the radiographs.
  
  
  RESULTS
  The most common abnormalities were increased vertebral body height (80%, nonspecific), talocalcaneal stippling (86%), periosteal cloaking (74%) and vertebral body rounding (50%). Unreported findings included sacrococcygeal sclerosis (54%) and vertebral body sclerosis (13%). Rickets and hyperparathyroidism-like (pseudohyperparathyroidism) changes (rarely reported) were found in 33% of cases. These changes invariably started in the newborn period and resolved by 1 year of age. The conversion from these early infantile radiographic features to dysostosis multiplex changes occurred in 41% of cases, and within the first year after birth.
  
  
  CONCLUSIONS
  Several findings strongly suggest the diagnosis of mucolipidosis II, including cloaking in combination with one or more of the following radiographic criteria: talocalcaneal stippling, sacrococcygeal or generalized vertebral body sclerosis, vertebral body rounding, or rickets/hyperparathyroidism-like changes in the perinatal/newborn/infancy period. These findings are not found in the other two forms of mucolipidosis nor in any of the mucopolysaccharidoses.
authors.affiliation: Pediatric Radiology, Lucile Packard Children's Hospital and Stanford University, 725 Welch Road, Palo Alto, CA, 94302, USA.
authors.forename: Lillian M
authors.initials: LM
authors.lastname: Lai
authors.affiliation: Pediatric Radiology, Lucile Packard Children's Hospital and Stanford University, 725 Welch Road, Palo Alto, CA, 94302, USA. rrlachman@earthlink.net.|International Skeletal Dysplasia Registry, University of California, Los Angeles, CA, USA. rrlachman@earthlink.net.
authors.forename: Ralph S
authors.initials: RS
authors.lastname: Lachman
mesh_terms: D000367:Age Factors; D002675:Child, Preschool; D005260:Female; D006801:Humans; D006961:Hyperparathyroidism / Q000150:complications; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D009081:Mucolipidoses / Q000000981:diagnostic imaging*; D011247:Pregnancy; D011859:Radiography; D012189:Retrospective Studies; D012279:Rickets / Q000150:complications; D012445:Sacrococcygeal Region / Q000000981:diagnostic imaging; D013131:Spine / Q000000981:diagnostic imaging
keywords: Dysostosis multiplex; Fetus; I-cell disease; Infant; Mucolipidosis type II; Newborn; Radiography