Chronic Mountain Sickness (Cms) Misdiagnosed As High Altitude Cerebral Edema (Hace) At Extreme Altitude (6400 M/21000 Ft)

Document Type : Case Report


Clinical Microbiology, Army College of Medical Sciences and Base Hospital, Delhi Cantt 110010, India


Introduction: Chronic mountain sickness (CMS) represents a syndrome of secondary polycythemia along with thrombocytopenia, altered hemorheology, pulmonary and systemic hypertension, and congestive heart failure, occurring due to hypobaric hypoxia-anoxia-induced erythropoiesis reported in both native mountain residents and new climbers after prolonged stays at high and extreme altitudes.
Case Presentation: A healthy non-smoker non-drinker reported occipital headache, breathlessness, and insomnia after an uneventful stay of 70 days at 6400 m/21000 ft. His hemoglobin was 21 gm/dL. The patient was diagnosed as having a case of CMS with a Qinghai CMS score >6. Therapeutic phlebotomy was performed; 350 mL was drained on two occasions, reducing his hemoglobin to 14.6 gm/dL.
Conclusion: The altered presentation, difficult diagnosis, evacuation, and long-term management highlighted in this case occurring at 6400 m/21 000 ft in the Karakoram Himalayas represents the insidious nature of altitude sickness in acclimatized subjects.


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