Pythiosis: An endemic fatal infectious disease

Abstract

Pythiosis is a life threatening infectious disease of humans and animals living in tropical and subtropical areas of the world. The causative agent is the fungus-like microorganism Pythium insidiosum , which is a member of the oomycetes. Most of the pathogenic oomycetes infect plants, several infect animals, and P. insidiosum is capable of infecting humans. Pythiosis in animals has been increasingly found worldwide, while the disease state in humans has been mostly reported in Thailand. Pythiosis has high rate of morbidity and mortality. Patients usually come with clinical features associated with an infection of eye (called ocular pythiosis, which presents with cornea ulcer or keratitis) or arteries (called vascular pythiosis, which presents with claudication and gangrenous ulcer at leg). Diagnosis of pythiosis can be difficult and delayed. Conventional antifungal drugs are not effective against P. insidiosum . Main treatment option for most patients with pythiosis is radical excision of infected organs. In advanced case, death is a final outcome. Information on the disease and its causative agent is limited. It is apparent that more needs to be done in the way of basic and applied research to provide insights into the disease, and thereby lead to the discovery of novel strategies for diagnosis and infection control, such as, better diagnostic assays, new antimicrobial agents, and vaccines. This talk will present update information on the disease, including biology of P. insidiosum , and diagnosis and treatment of pythiosis.