Psorosperm Explained

Psorosperm (from the Greek ψωρα itch and σπερμα seed) is a former name of a number of parasitic protozoa that produce cystlike or sporelike structures in the tissue of hosts. The term is now essentially obsolete.

• Some that affect vertebrate hosts are now called coccidia.
• Others, such as the cause of pébrine in silkworms, are now recognized as microsporidians, and some are myxosporidians.
• The genus Psorospermium (which includes the species Psorospermium haeckeli) itself is a parasite of crayfishes, and belongs to an enigmatic group of unicellular organisms that some biologists think may be related to the common ancestors of animals and fungi.^[1]

J. Müller introduced the term in German (as Psorospermien) in 1841.^{[2] [3]}

Psorosperm was at one point believed to be the cause of Darier's disease.^{[4] [5]}

"Psorospermiasis" is classified under 136.4 in ICD-9.^[6]

Notes and References

1. Ragan MA, Goggin CL, Cawthorn RJ, etal . A novel clade of protistan parasites near the animal-fungal divergence . Proc. Natl. Acad. Sci. U.S.A. . 93 . 21 . 11907–12 . October 1996 . 8876236 . 38157 . 10.1073/pnas.93.21.11907. 1996PNAS...9311907R . free .
2. Müller J. 1841: Über Psorospermien. Arch. Anat. Physiol. Wissensch. Med. 5: 477–496
3. Book: Revere Randolph Gurley. The Myxosporidia, or Psorosperms of fishes: and the epidemics produced by them. 10 April 2010. 1894. Govt. print. off.. 72.
4. Web site: Arch Derm Syphilol -- Excerpt: KERATOSIS FOLLICULARIS (DARIER'S DISEASE) A VITAMIN A DEFICIENCY DISEASE, February 1941, PECK et al. 43 (2): 223 . https://archive.today/20110716115320/http://archderm.highwire.org/cgi/content/summary/43/2/223 . 2011-07-16 . dead .
5. F. J. Darier. De la psorospermose folliculaire végétante. Étude anatomo-pathologique d'une affection cutanée non décrite ou comprise dans le groupe des acnés sebacées, cornées, hypertrophiantes, des kératoses (ichtyoses) folliculaires, etc. Annales de dermatologie et de syphilographie, Paris, 1889, 10: 597-612.
6. Web site: 2009 ICD-9-CM Diagnosis Code 136.4 : Psorospermiasis .