He was a co-founder and president of four different professional societies and was the founding chairman of the Division of Dermatology at the University of California, San Diego Medical Center.
He completed a residency in his field (which was then called Dermatology and Syphilology) as a Medical Fellow at the Mayo Clinic in Rochester, Minnesota, earning an M.S.
[5] In 1969 he became a clinical professor of medicine and pathology for the fledgling medical school at the University of California, San Diego, serving as the founding chair of the Division of Dermatology until 1974.
[6] His students at the Naval Hospital compiled a list of his aphorisms and sayings, which they called “Nick’s Nuggets,” as a teaching aid for residents.
[4] In the 1940s he created the Clinicopathologic Conference, a study of individual cases from both the clinical and pathological standpoint, at the annual meeting of the Pacific Dermatologic Association.
[10] Citizen of the Year, San Diego City Club, 1983[citation needed] In 1989 when Nickel died, then-Senator Pete Wilson eulogized him on the floor of the Senate and placed his obituary in the Congressional Record.