Congenital aural atresia in 18q deletion or de Grouchy syndrome.

Objective: To study the occurrence of congenital aural atresia in patients with a deletion of the long arm of chromosome 18 (18q- deletion or de Grouchy syndrome).

Study Design And Patients: This retrospective study presents an overview of the otologic findings in 33 Dutch and Belgian patients with a deletion of 18q.

Materials And Methods: Detailed information on otorhinolaryngological findings was obtained from otorhinolaryngologists and audiologic centers. Data about medical and developmental history and phenotype were collected from physical examination by a clinical geneticist, by interviewing parents, and by reviewing medical and developmental records. Determination of deletion breakpoints was established by routine karyotyping, prometaphase studies, and/or fluorescence in-situ hybridization (FISH).

Results: Twenty out of 33 patients (61%) with a deletion 18q had congenital aural atresia (CAA) ranging from narrow external auditory canals to meatal atresia type IIB. Fifteen patients (45%) had conductive hearing impairment (range: 30 dB-70 dB). Twelve of these 15 patients (80%) received hearing aids, which resulted in improved hearing but not in speech development. CAA was found only in patients with a distal deletion of 18q (including band 18q22.3 or 18q23) and not in patients with more proximal 18q deletions.

Conclusion: In patients with narrow ear canals or meatal atresia and unexplained mental retardation, chromosomal analysis is indicated. If de Grouchy syndrome is diagnosed in a young patient, auditory examination and surveillance are highly recommended.