I doubt seriously whether there is a more humiliating moment in the life of a medical man, either as teacher or practitioner, than when asked by a student or patient, "What is the cause of this?" and he is forced to say, "I do not know."
While it is true that few diseases of the skin end fatally, they not infrequently play havoc with the lives of the afflicted. I recall the case of an otherwise beautiful woman whose life was devoted to social service work among the handicapped, the blind and the crippled, who gave up her work and is now living in seclusion because of the marring effect of vitiligo. In another instance, one of the most brilliant young lawyers of our community was forced to withdraw from a promising career in both law and politics, for the same reason. And I have never been able to satisfy
HAASE M. "ETIOLOGY UNKNOWN". JAMA. 1923;81(9):703-704. doi:10.1001/jama.1923.02650090001001