Mount Everest has several things in common with the disease multiple sclerosis. Both can cause weakness and numbness, damage nerves, and debilitate humans. Even the most fit people can succumb.
This week, though, one man who has the disease offered a glimmer of hope by successfully ascending the world's highest mountain.
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Niels van Buren, a 37-year-old Internet marketing professional from Haarlem in the Netherlands, was about to go climb Mount Kilimanjaro six years ago with several friends when he received an MS diagnosis. The disease messes with the brain and the spinal cord by attacking the protective sheath covering nerves. Over time it can cause crippling disability for some patients.
Undaunted, van Buren and his crew went on the trip. Then in 2011 they started a foundation called Mission Summit that brings attention to the disease through expeditions and raises money for research. Van Buren also begin training for Everest by climbing other mountains, including the 23,405-foot tall Lenin Peak in the former Soviet Union.
Before setting out for the Himalayas this spring, van Buren noticed some tingling in his foot, Dutch newspaper Algemeen Dagblad reported. Fortunately his neurologist helped him manage what was going on, and he regained feeling in time. Early on Friday morning, van Buren reached the summit.
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"It all feels a little unreal," he said in an update on the Mission Summit site. "I knew beforehand that it would be a bizarre journey, but no one can prepare for the extremes I have experienced."
This season on Everest has already been deadly. Australian climber Maria Strydom and Dutch climber Eric Arnold had each reached the summit but experienced altitude sickness on the way down that took their lives.
While van Buren is the first male with MS to climb Mount Everest, American mountaineer Lori Schneider, who developed the disease in 1999 when she was 43 years old, made it up and back in 2009 as part of a seven summits quest.
Multiple sclerosis symptoms vary widely, as the Mayo Clinic staff points out. There are currently treatments, but no cure.
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Mission Summit posted a Facebook update saying that van Buren had come down from Everest and made it safely to Kathmandu for several days of recovery.
Before he left for Everest, van Buren discussed the deterioration MS can cause. "The feelings in my legs or arms may just be gone," he told the Dutch edition of Metro News. "And that is why I want to do this."
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