(Pretend you are in south Louisiana overlooking a wetlands area)
Phycomycoses are diseases caused by several different infective agents.  Pythiosis and lagenidiosis are two specific types of infection that are grouped under this heading.  The ailments are caused not by true fungi, but by a group of organisms known as oomycetes.  Oomycetes are single celled or filamentous organisms with both sexual and asexual reproductive patterns.  Pythium and Lagenidium are water molds often found in tropical climates around the world where they are able to thrive in warm climates with many available aquatic habitats.  During the hot, damp summers a danger invisible to the human eye lurks in these habitats throughout the Gulf Coast Region.  This danger is the oomycetes, which are capable of infecting mammals, even humans.  Pythium insidiosum begins its attack on the body after being ingested when contaminated water is ingested or infecting through open wounds. Gastrointestional symptoms can include vomiting, diarrhea, and a mass in the stomach.  These diseases are found not only in the Gulf Coast Region of the United States, but in places as far flung as southeast Asia and New Zealand.  Unlike the gastrointestinal infections caused by Pythium, Lagenidium sp. usually infects mammals in subcutaneous tissues, causing sores to develop on the extremities of the body.  Both diseases are treated through surgery, although recurrence of the infection is common.  Anti-fungal medications do little to aid in the treatment of the disease, an early indication that the infectious agents were not true fungi.  Currently only one drug, Caspofungin, is available that targets water molds infections specifically.  Caspofungin works by inhibiting cell wall synthesis in the oomycete.  This treatment option, however, like all other phycomycosis treatment plans, is extemely expensive, and the prognosis for animals infected with a phycomycosis is almost always very poor.  --B. Cranfield

Dog infected with Lagenidium resulting in subcutaneous lesions.
Picture courtesy of the Center for Disease Control.

Read more about it:


Return to Virtual Highway of Biological Historical Markers Index
You write the next one!
Last modified 26 April 2004
Return to Mycology at LSU