Neuronal ceroid lipofuscinosis diagnosed via skin biopsy

Broadening phenotype of adenylosuccinate lyase deficiency: A novel clinical pattern resembling neuronal ceroid lipofuscinosis

We describe a 7-year-old boy presenting with a developmental encephalopathy, severe epilepsy, retinopathy with salt and pepper fundus, and ultrastructural skin alterations resembling a neuronal ceroid lipofuscinosis. Whole exome-sequencing detected biallelic variants in the ADSL gene (c.65C > T [p.(Ala22Val)] and c.340 T > C [p.(Tyr114His)]). The increase of SAICAR and S-Ado in blood and urine was consistent with the pattern of adenylosuccinate lyase deficiency (OMIM 103050). An unusual increase of AICAR, that was due to a residual ADSL enzyme activity of about 28%, was also detected.

Neither salt and pepper retinopathy nor ultrastructural skin alterations had been reported in ADSL deficiency before. Impaired purinergic signaling inside the retina is probably involved in visual failure. Ultrastructural alterations in fibroblasts suggest a possible damage of autophagic processes, whose role in the pathogenesis of neurological dysfunction deserves further study.

Late infantile neuronal ceroid lipofuscinosis: A case report with review of literature

Neuronal ceroid lipofuscinosis (NCL) are a group of genetically mediated neurodegenerative disorders affecting children and young adults. They are characterized by global mental and motor deterioration, vision loss, and epilepsy ultimately resulting in death. Of the various types, late infantile variety is the 2^nd most common form of NCL. Here the authors report a case of a 9-year-old boy who presented with progressive mental and social deterioration since the age of 2½ years. As the disease progressed, he developed progressive vision loss, gait ataxia, action myoclonus, and epilepsy. Electroencephalogram revealed generalized sharp and slow wave discharges with background slowing. Magnetic resonance imaging of the brain revealed diffuse cerebral and cerebellar atrophy markedly affecting the cerebellum along with periventricular T2 hyperintensities. Skin biopsy from axilla revealed characteristic intracytoplasmic eosinophilic inclusions and periodic acid Schiff positive bodies within the eccrine ducts suggestive of NCL.