Molar Tooth Sign Is Not Pathognomonic for Joubert Syndrome

Abstract

A 12-year-old girl was admitted for the evaluation of epilepsy and psychomotor retardation. She was born at term after an uneventful pregnancy. There was no consanguinity. Developmental milestones were delayed and she had been treated for epilepsy since 3 months of age. She was walking with support and was able to say a few words like “mama” and “dada.” She had dysmorphologic findings including broad nasal tip, frontal bossing, hypertelorism, tongue hamartomas, notching of the teeth (Fig 1), high arched palate, low set ears, and bilateral preaxial poly-syndactyly of bilateral feet with bifid hallux. Deep tendon reflexes were hyperactive. Echocardiography, abdominopelvic ultrasonography, and ophthalmologic examinations were normal. Brain magnetic resonance imaging revealed molar tooth sign and vermian agenesis (Fig 2). A diagnosis of Varadi-Papp syndrome (orofaciodigital syndrome type VI) was made based on her clinical and radiologic findings. Genetic analysis of INPP5 E and TMEM216 genes revealed no mutation. Figure 2T1-weighted axial scan showing “molar tooth sign.” View Large Image Figure Viewer Download Hi-res image The Molar Tooth Sign Is Pathognomonic for Joubert Syndrome!Pediatric NeurologyVol. 50Issue 6PreviewAs researchers deeply involved in clinical, neuroimaging, and genetic studies on Joubert syndrome (JS), we read with great interest the article by Dirik et al.1 The authors report on a 12-year-old girl with intellectual disability, tongue hamartomas, preaxial poly-syndactyly of both feet, and notching of the teeth. Brain magnetic resonance imaging showed a molar tooth sign (MTS). The authors correctly made the diagnosis of oral-facial-digital syndrome type VI (OFDVI), and based on this they concluded that the MTS is not pathognomonic for JS, but may be seen in other disorders including OFDVI. Full-Text PDF Clinical Syndromes or Ciliopathies Associated With Molar Tooth SignPediatric NeurologyVol. 50Issue 6PreviewWe have read with interest the letter to the Editor by Poretti et al.1 regarding our publication “Molar tooth sign is not pathognomonic for Joubert syndrome.”2 We agree with the authors that a distinction between Joubert syndrome, Joubert syndrome-related disorders, and individual syndromes included in the Joubert syndrome-related disorders does not appear to contribute to the diagnostic definition of patients and may be confusing. The authors suggested a less confusing and clinically more relevant nomenclature, which uses only the term Joubert syndrome and adopt a descriptive classification based on the extent of involvement. Full-Text PDF