Neuronal ceroid lipofuscinosis 11 (CLN11) presenting with early-onset cone-rod dystrophy and learning difficulties.

Neuronal Ceroid Lipofuscinosis 11 (CLN11) is an ultra-rare subtype of adult-onset Neuronal Ceroid Lipofuscinosis. Its phenotype is variable and not fully known. A 21-year-old man was evaluated in our neurogenetic outpatient clinic for early onset complex phenotype, including learning difficulties, cerebellar ataxia, cone-rod dystrophy, epilepsy, and dystonia. The patient was submitted to neurological and neuropsychological assessment, neuro-ophthalmological tests, brain MRI, EEG and whole exome sequencing. A homozygous frameshift variant (NM_002087.4: c.768_769dup; p.Gln257Profs*27) was found. Distinct type descriptions, as in this case, increase the clinical spectrum of the disease.