Skip to
  1. Homepage
  2. Rare diseases
  3. Search
Simple search

Simple search

(*) mandatory field


Other search option(s)

Neuronal intranuclear inclusion disease

Synonym(s) -
Prevalence Unknown
Inheritance -
Age of onset All ages
  • G31.0
  • C1863843
  • C537395
MedDRA -


Neuronal intranuclear inclusion disease (NIID) is a very rare multisystem neurodegenerative disorder characterized by the presence of eosinophilic intranuclear inclusions in neuronal and glial cells, and neuronal loss. Infantile, juvenile, and adult-onset cases have been described in approximately 30 patients word-wide. As any part of the nervous system can be affected (central, peripheral, and autonomic nervous systems), the clinical manifestations depend on the sites involved, and widely vary. The most common neurological signs include ataxia, extra-pyramidal signs (tremor and oculogyral crises), lower motor neuron findings (absent deep tendon reflexes, weakness, muscle wasting, foot deformities), and less apparent behavioural or cognitive difficulties. Dementia is reported as a predominant neurological symptom in adult patients, while infantile/juvenile cases show disproportionate ataxia and other movement symptoms. Occasionally, gastrointestinal dysmotility with severe weight loss may be present, if the enteric nervous system is involved. NIID may be diagnosed by a full thickness rectal biopsy. The differential diagnosis should consider spinocerebellar ataxias, progressive juvenile parkinsonism and dystonia. Most cases are sporadic. Despite reports of several familial cases (including a pair of identical twins), no causative gene has been identified. Autosomal dominant transmission has been suggested in these families. NIID is slowly progressive (within 10 to 20 years) and fatal. There is no cure or treatment that slows the progression of the disease. Symptomatic treatments may improve the quality of life.

Expert reviewer(s)

  • Pr Bertrand FONTAINE

(*) Required fields.

Attention: Only comments seeking to improve the quality and accuracy of information on the Orphanet website are accepted. For all other comments, please send your remarks via contact us. Only comments written in English can be processed.

Captcha image
The documents contained in this web site are presented for information purposes only. The material is in no way intended to replace professional medical care by a qualified specialist and should not be used as a basis for diagnosis or treatment.