altitude sickness acute disease acute mountain sickness https://rarediseases.info.nih.gov/diseases/5730/acute-mountain-sickness high altitude pulmonary oedema altitude anoxia UMLS:C0238284 ICD9:993.2 acute mountain sickness SCTID:78590007 altitude sickness MEDGEN:536790 MONDO:0021811 high altitude pulmonary edema high altitude cerebral oedema Mountain sickness high altitude cerebral edema Acute mountain sickness is characterized by altitude sickness that affects otherwise healthy persons, develops within hours after arriving at altitude, and results in functional impairment from symptoms that may include headache, anorexia, nausea, vomiting, dizziness, fatigue, and sleep disturbances.