Rare diseases · Sign or symptom
Coma
HP:0001259
What it means
The complete absence of wakefulness and consciousness, which is evident through a lack of response to any form of external stimuli.
Coma is generally a result of diffuse or extensive involvement of both hemispheres of the brain or lesions in the brainstem.
In everyday care
Most people with this sign do not have a rare disease — it appears in common conditions far more often. These general reference pages cover the same topic:
Rare diseases that can present with this85
Very common80–99%
8- ABetaL34V amyloidosis
- Congenital hyperinsulinism due to HNF4A deficiency
- Familial acute necrotizing encephalopathy
- Non-insulinoma pancreatogenous hypoglycemia syndrome
- Vitamin B12-responsive methylmalonic acidemia
- Vitamin B12-unresponsive methylmalonic acidemia
- Vitamin B12-unresponsive methylmalonic acidemia type mut-
- Vitamin B12-unresponsive methylmalonic acidemia type mut0
Common30–79%
11- ABeta amyloidosis, Italian type
- Acquired aneurysmal subarachnoid hemorrhage
- Alpers-Huttenlocher syndrome
- Beta-ketothiolase deficiency
- Carnitine palmitoyl transferase 1A deficiency
- Idiopathic catatonia
- Immune-mediated thrombotic thrombocytopenic purpura
- Lujo hemorrhagic fever
- Marchiafava-Bignami disease
- Ornithine transcarbamylase deficiency
- Thrombotic thrombocytopenic purpura
The range is how often this sign appears among people diagnosed with each disease — it is not a probability of having any of them. Many of these signs also occur in common, non-rare conditions. A sign on this page is a conversation to have with a clinician, not a conclusion.
Part of the broader category
Also called: Persistent vegetative state · Stupor · Trance · Unconsciousness
Tracking symptoms like this for someone? Eleplan keeps symptoms, diagnoses, medications and every specialist in one plan.
Start free with EleplanThis page uses the Human Phenotype Ontology (2026-06-23) — Human Phenotype Ontology Consortium, hpo.jax.org. Disease associations from Orphanet (INSERM), CC BY 4.0. Content is educational and is not medical advice.