Psorosperm (from the Greek ψωρα itch and σπερμα seed) is a name formerly given to a number of parasitic protozoa which produce cystlike or sporelike structures in the tissue of hosts, but now essentially obsolete.
The term was introduced in German (as Psorospermien) by J. Müller in 1841.
Psorosperm was at one point believed to be the cause of Darier's disease.
"Psorospermiasis" is classified under 136.4 in ICD-9.
References
Psorosperm Wikipedia(Text) CC BY-SA