gms | German Medical Science

Objectives/Interrogation: Joubert syndrome (JS), first described by Marie Joubert in 1968, is a congenital anomaly characterized by episodic hyperpnea, abnormal eye movement, ataxia, and intellectual disability. Congenital deformities of the extremities are mostly postaxial polydactyly of the hands and preaxial polydactyly of the feet. Typically, a y-shaped metacarpal bone between the middle and ring finger is seen on x-ray. Our patient had bilateral polysyndactyly of the ring finger from the middle phalanx to distal phalanx in the right hand and from the metacarpal bone to the distal phalanx on the left and polydactyly from the proximal phalanx to the distal phalanx of the right great toe. Here, we describe this atypical case in comparison with previous reports.

Methods: Case report: The patient was a male infant born in normal vaginal delivery with a weight of 3278g at 38 weeks and 3days' gestation. He was referred to our hospital due to screening because of tongue tumor and hand malformations. Examination revealed abnormal eye movement, polydactyly of the ring fingers bilaterally, and polysyndactyly of the right great toe with the typical molar tooth sign on magnetic resonance imaging. There were no retinal, renal, hepatic, or orofacial defects. Our comprehensive literature search of PubMed on congenital hand anomalies in JS revealed that from 1968 to 2017.

Results and Conclusions: Only 12 reports have described about polydactyly in detail. The average of morbidity of polydactyly is 30.19% (8-100%). In our case, first, separation was successfully performed for the right hand and right foot, and then 3 months later for the left hand. The incidence of JS is between 1/80,000 and 1/100,000 live births. JS is classified into 6 types, pure JS, JS with ocular defect, JS with renal defect, JS with oculorenal defects, JS with hepatic defect, and JS with orofaciodigital defects. Our case was diagnosed as JS with orofaciodigital defects. Several candidate genes were published such as AHI1,CC2D2A,CEP290, ARL13B,C5ORF42,TCTN2 in JS with orofaciodigital defect, but we have not done genetic testing yet.

Considering the associated intellectual disability, it is important to make use of the fingers easier by surgery because of the lack of active flexion in the right ring finger. Careful observation and guidance for the patient and the family are also important.