Neuronal intranuclear inclusion disease showing intranuclear inclusions in renal biopsy 12 years earlier

Neuronal intranuclear inclusion disease (NIID) is a slowly progressive neurodegenerative disorder characterized by eosinophilic hyaline inclusions in neuronal and somatic cells on histopathologic examination.1,2 NIID occurs in both sporadic and hereditary forms, and shows various clinical manifestations, including dementia and cerebellar ataxia.3 NIID is a rare disease, and can be difficult to distinguish from other leukoencephalopathies. Several recent case reports have described NIID following the description of pathognomonic MRI and skin biopsy findings of NIID.4 The time points at which the eosinophilic intranuclear inclusions of NIID may form and be detectable in CNS and systemic organs remain to be elucidated. We present a case of sporadic NIID demonstrating eosinophilic intranuclear inclusions in a renal biopsy obtained 12 years preceding diagnosis.