title: X-linked hypophosphatemic rickets without "rickets".
abstract: Wrist and knee radiographs from children with X-linked hypophosphatemic rickets were analyzed and compared with those from normal children and children with established rickets to assess whether radiographically apparent rickets is a consistent abnormality in X-linked hypophosphatemia. The absence or presence of rickets was correctly identified in 94.8% of wrist and knee films from normal and positive controls. In contrast, patients with X-linked hypophosphatemia exhibited rachitic abnormalities in only 5 of 11 wrist and 13 of 15 knee radiographs. As a result, 4 patients within this study group had rickets at the knee and not at the wrist, whereas 5 displayed classic defects at both sites. Perhaps more important, 2 patients, aged 3.8 and 5.2 years, displayed no evidence of rickets in either wrist or knee films, although relatives exhibited demonstrable rachitic abnormalities. Our data indicate that radiographically detectable rickets is a variable abnormality of X-linked hypophosphatemia and does not provide an unambiguous index for the diagnosis of this disease.
authors.affiliation: Department of Medicine, Duke University Medical Center, Durham, NC 27710.
authors.forename: M J
authors.initials: MJ
authors.lastname: Econs
authors.forename: J R
authors.initials: JR
authors.lastname: Feussner
authors.forename: G P
authors.initials: GP
authors.lastname: Samsa
authors.forename: E L
authors.initials: EL
authors.lastname: Effman
authors.forename: J B
authors.initials: JB
authors.lastname: Vogler
authors.forename: S
authors.initials: S
authors.lastname: Martinez
authors.forename: N E
authors.initials: NE
authors.lastname: Friedman
authors.forename: L D
authors.initials: LD
authors.lastname: Quarles
authors.forename: M K
authors.initials: MK
authors.lastname: Drezner
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D005260:Female; D008040:Genetic Linkage; D006801:Humans; D007015:Hypophosphatemia, Familial / Q000000981:diagnostic imaging / Q000453:epidemiology* / Q000235:genetics; D007223:Infant; D007717:Knee / Q000000981:diagnostic imaging; D008297:Male; D015588:Observer Variation; D015995:Prevalence; D011859:Radiography; D012279:Rickets / Q000000981:diagnostic imaging / Q000453:epidemiology* / Q000235:genetics; D016037:Single-Blind Method; D014953:Wrist / Q000000981:diagnostic imaging; D014960:X Chromosome