Discovery of a large deletion of KAL1 in 2 deaf brothers.

Objectives: Kallmann syndrome (KS) usually combines an anosmia and a hypogonadotrophic hypogonadism. Hearing impairment was described in a few cases of KS. Our objective is to describe an unusual presentation of KS in 2 cases and to explore the pattern of inheritance in this family.
Patients: Two brothers presented with a sensorineural hearing impairment associated with cryptorchidism and abnormal movements.
Results: Genome-wide array analysis identified a large deletion of KAL1 in both patients confirming the diagnosis of Kallmann syndrome. The absence of familial history has been explained by a somatic mosaicism identified in their mother.
Conclusion: The description of a hearing defect in 2 brothers with Kallmann syndrome allows asserting that deafness is part of the clinical features of this disease and must lead the physician to monitor the hearing function of Kallmann patients.