Dental and Orofacial Skeletal Findings in Young Male Twins with Mild Lowe Syndrome

Lowe syndrome (LS), also reported as oculocerebrorenal syndrome (OCRL), is a rare genetic X-linked recessive disorder. It affects more males than females [1,2] and its prevalence was estimated at 1 out of 500.000 individuals with only 190 individuals affected in the year 2000 [3,4]. LS is caused by a mutation in the OCRL1 gene localized to Xq24-Xq26, resulting in a deficiency of an enzyme called phosphatidylinositol 4,5-biphosphate which regulates the normal activity of the Golgi apparatus [5-7]. Several reports described the combination of ocular manifestations (congenital cataract, glaucoma, and nystagmus), manifestations of the central nervous system (mental retardation), and of the kidneys (reduced ammonia production, proteinuria, phosphaturia, and aminoaciduria) for the identification of the LS [4,8-11]. Unusual and atypical renal features have also been reported in a mildly affected boy [12]. Other significant clinical manifestations include joint hyper mobility, scoliosis, frontal bossing, thin and sparse hair, protruding ears, decreased muscle reflexes and hypotonia [1,13]. Oral manifestations associated with LS are more scarcely described and consist of isolated case reports. The reported abnormalities include cases with taurodontism of molars [14,15] crowding and constricted palate, constricted dental arches [4] underdevelopment of the maxilla and mandible, impaction of permanent teeth, gross periodontal disease and severe bone loss. Multiple eruption cysts and odontogenic cyst formation was also reported [1,4] as well as enamel hypoplasia by some [16] and no hypoplastic enamel by others. Delayed tooth eruption was reported in another patient while no delay in the eruption of primary teeth was reported in another. Moreover, in the one case studied with the lateral cephalometric radiography, the analysis showed an increased vertical facial height [10]. The present report provides findings on male twins with particular reference to the dental findings and the maxillofacial cephalometric characteristics. It also provides results of the orthodontic treatment performed to ameliorate the dental and skeletal relationships. We believe that reports of different patients suffering of this rare syndrome are useful in order to enhance knowledge about LS, to better define the maxillofacial manifestations related to it, and to approach rehabilitation solutions for the improvement of their quality of life.