Chronic mountain sickness on the Qinghai-Tibetan plateau

摘要

In 1925, Carlos Monge Medrano described a new illness that he called ' erythremia syndrome of high altitude', which is now known as 'chronic mountain sickness' (CMS) or 'Monge's disease' in his honour. His patient was a 38-year old man who was a resident of Cerro de Pasco (4330 m), Peru, and had a red cell count of 8. 86 million, much higher than the average value at that altitude. Polycythemia has frequently been used as a marker of CMS, so 'high altitude polycythemia' is a synonym of CMS. CMS is a syndrome of loss of adaptation to life at high altitude, which occurs to indigenous or long-term residents at altitude above about 3000 m. This clinical syndrome is characterized by excessive erythrocytosis and severe hypoxemia and by reversibility on descent. CMS is found most commonly in the Andes. In China, the first report of ' high altitude polycythemia' (HAPC) was by Wu of 82 cases living at altitudes between 3008 m and 4888 m in Qinghai-Tibet. The clinical features of the patients were related to erythrocytosis and were similar to those of CMS or Monge' s disease reported from Peru. The average haemoglobin (Hb) concentration and haematocrit (Hct ) values were (228 +-14) g/L, and (76. 8 +- 3. 5) % , respectively. Over the next twenty-four years, more than one thousand similar cases were reported of persons who permanently resided at high altitude. However, many questions about CMS developed in residents of the Qinghai-Tibetan plateau have been raised: How to diagnose CMS in China? Does CMS really exist in indigenous Tibetans? What are the epidemiological characteristics of CMS among Tibetan populations? What are the predisposing factors that put persons at risk for CMS? What is the pathogenesis of CMS in Tibet? Based on the recent achievements of high altitude medicine attained by the Chinese researchers, these and other questions are discussed in this brief review article.