>>> Google says the number was Washington University St. Louis, Dept. of Dermatology. <<<
"Google" doesn't say much of anything -- all it does is index other sites. The trustworthyness of the indexed sites varies and may be subject to question.
When I searched for this number, I saw only one entry from this site in the top three or four pages of listings that had anything to do with Washington University or with dermatology:
http://companies.findthebest.com/l/30830146/W ... -Saint-Louis-MO
I'm not convinced this listing is either accurate or up-to-date. If you want the real scoop, try contacting the university's dermatology department directly:
http://dermatology.wustl.edu/content/contacts.html
I suggest you call one or more of the numbers listed in association with addresses in the 63110 zip code. The other addresses seem rather distant from the location given in the "findthebest" web site. If the number is real and not being spoofed, you should be able to find out who is calling you by asking one of the contacts on the official web site.