The risk of developing AMS is high on Mt Kilimanjaro. Although taking an extra day to acclimatize with the use of acetazolamide did provide some protection against AMS, ideally trekkers need a more gradual route profile for climbing this mountain.

OBJECTIVES To review the patient characteristics and management of 56 cases of high altitude pulmonary edema (HAPE) at the Pheriche Himalayan Rescue Association Medical Aid Post, and to measure the use of medications in addition to descent and oxygen. METHODS In a retrospective case series, we reviewed all patients diagnosed clinically with HAPE during the 2010 Spring and Fall seasons. Nationality, altitude at onset of symptoms, physical examination findings, therapies administered, and evacuation methods were evaluated. RESULTS 23% of all patients were Nepalese, with no difference in clinical features compared to non-Nepalese patients. 28% of all patients were also suspected to have high altitude cerebral edema. 91% of all patients developed symptoms at an altitude higher than the aid-post (median altitude of onset of 4834m). 83% received oxygen therapy; 87% received nifedipine, 44% sildenafil, 32% dexamethasone, and 39% acetazolamide. Patients administered sildenafil, dexamethasone, or acetazolamide had presented with significantly lower initial oxygen saturations (p ≤.05). After treatment, 93% of all patients descended; 38% descended on foot without a supply of oxygen. CONCLUSIONS A significant number of patients presenting to the Pheriche medical aid post with HAPE were given dexamethasone, sildenafil, or acetazolamide in addition to oxygen, nifedipine and descent. This may be related to perceived severity of illness and evacuation limitations. While no adverse effects were observed, the use of multiple medications is not supported by current evidence and should not be widely adopted without further study.

The I-allele rather than the D-allele of the human angiotensin converting enzyme (ACE) gene has been associated with high-altitude mountaineering success. We investigated whether the I-allele was associated with summit success, and also with AMS development, in altitude-naïve trekkers. Subjects ascended from 1,860 m to the summit over 4 days (n = 34, 'direct-profile') or 5 days (n = 82, 'slower-profile'). Proportionally more II direct-profile subjects were successful than ID or DD, although the difference was not significant (100% of II subjects, 52% ID and 43% DD, P = 0.09). There was no difference in success amongst subjects on the slower-profile (50% II, 45% ID and 58% DD, P = 0.54). There was a non-significant trend for increasing AMS scores in ID/DD subjects. Amongst tourist trekkers on Mt. Kilimanjaro the I-allele is not associated with summit success. No evidence is found to support an association between ACE genotype and AMS development.

More than 30 000 climbers attempt to reach the summit of Mount Kilimanjaro every year; it is likely that a significant proportion have diabetes [1]. Summit success rates in climbers with diabetes appear to be similar to those without diabetes [2,3], with the exception of a study carried out on Mount Kilimanjaro in 2001, in which all 15 climbers with Type 1 diabetes failed to reach the summit [4]. One explanation suggested for this discrepancy is the short time of 5 days allowed for climbers to reach the summit of Kilimanjaro at 5895 m.Whilst investigating altitude physiology and acute mountain sickness (AMS) on tourist trekkers attempting Kilimanjaro, we compared a group of 11 climbers with Type 1 diabetes [six males, five females, age 20 ± 7.6 years (mean ± SD ), body mass index (BMI) 22.0 ± 2.3 kg/m 2 ] with 275 subjects without diabetes (180 males, 95 females, age 33 ± 12.1 years, BMI 23.0 ± 2.8 kg/m 2 ). All subjects gave written informed consent and ethical approval was obtained from the Tanzanian Commission for Science and Technology (COSTECH reference 2005-261-NA-2005. Eight of the eleven diabetic climbers (73%) took regular acetazolamide as AMS prophylaxis, compared with 66 (24%) of subjects without diabetes. The climbers with diabetes attempted the mountain over 7 days, with two acclimatization nights at 3700 m during ascent. Seven of the eleven climbers (64%) reached the summit, a success rate comparable with that of the rest of the hiking population (61%); three reached 5600 m, and one reached 4700 m. Reasons for turning back were AMS symptoms of dizziness, fatigue and nausea.AMS scores (Lake Louise questionnaire) were not different between those with or without diabetes (median = 6, range 1-15 versus median = 6, range 1-21 respectively on the summit day, P = 0.389). The physiological response to high altitude in the diabetic group was not different to that in nondiabetic climbers (SaO 2 , respiratory rate, heart rate and lung function). Although we did not have access to capillary blood glucose measurements, members of the group monitored their own measurements regularly whilst on the mountain.Mount Kilimanjaro is an extremely popular tourist mountain, and the risk of AMS is high for everyone. Climbers with Type 1 diabetes should not have a higher rate of AMS and should not have a reduced chance of success if they are well prepared and acclimatize, and we suggest the two extra acclimatization nights and the high rate of acetazolamide use were critical factors in this group's success. References1 Brubaker PL. Adventure travel and type 1 diabetes: the complicating effects of high altitude. Diabetes Care 2005; 28 : 2563 -2572. 2 Pavan P, Sarto P, Merlo L, Casara D, Ponchia A, Biasin R et al . Extreme altitude mountaineering and type 1 diabetes: the Cho Oyu alpinisti in Alta Quota expedition. Diabetes Care 2003; 26 : 3196-3197. 3 Admetlla J, Leal C, Ricart A. Management of diabetes at high altitude. Br J Sports Med 2001; 35 : 282-283.