Childhood apraxia of speech without intellectual deficit in a patient with cri du chat syndrome

We report an 11-year-old girl for whom the diagnosis of cri du chat syndrome (CdCS) was made during a genetic investigation of childhood apraxia of speech. The patient presented with the classic chromosome 5 short arm deletion found in CdCS. The microdeletion, characterised using aCGH (array Comparative Genomic Hybridisation), was 12.85 Mb, overlapping the 5p15.2 and 5p15.3 critical regions. CdCS is typically associated with severe mental retardation while this patient had normal intellectual performance, confirmed by normal results from categorisation tasks. This mild phenotype was assessed using a comprehensive cognitive battery. Language evaluation showed normal receptive vocabulary scores, in contrast with obvious oro-facial dyspraxia. Disabled fine motor skills were confirmed as well as weak visuo-spatial reasoning abilities. In conclusion, fine cognitive assessment may be worthwhile for patients with CdCS since good intellectual functioning may be masked by severe speech and gestural dyspraxia, thus requiring specific teaching and rehabilitation strategies.

► Children bearing a classical 5p deletion may have spared intellectual skills.
► Good intellectual functioning may be masked by speech and gestural apraxia.
► Fine and comprehensive cognitive assessment is worthwhile in 5p deletion.
► Genetic studies are useful in the diagnosis of complex learning disorders.