Introduction

Classification

Taxonomy

• Aquatic micro-organism, fungus.

Active Forms

Clinical Effects

Epidemiology

Habitat

• Found in aqueous environments.

Lifecycle

• Reproduces asexually in aqueous environment to form motile zoospores which infect the host.
• Reproduces sexually on solid substrates via male antheridia and female oogonia.

Transmission

• Animals infected by standing in or drinking water infected with zoospores.

Pathological effects

• Causes cutaneous pythiosis (swamp cancer or Florida horse leeches).
• Skin lesions are pyogranulomatous or fibrogranulomatous.
• Disease is chronic and progressive. In horse lesions <45 cm, discharging swellings.
• Lesions usually on ventral trunk, head or extremities.
• Nasal mucosa may be involved.
• Hyphae can be found within granulomatous coagula ('leeches').
• Dogs can also have intestinal form; more rarely systemic.
• Recently reported as cause of intraprostatic infection.

Control

Control via animal

Surgery

• Excise affected tissue.

Control via chemotherapies

• Amphotericin B Amphotericin B (plus surgery).

Diagnosis

Further Reading

Publications

Refereed papers

• Recent references from PubMed and VetMedResource.
• Jaeger G H, Rotstein D S & Law J M (2002) Prostatic pythiosis in a dog. J Vet Intern Med 16 (5), 598-602 PubMed.
• Bentinck-Smith J, Padhye A A, Maslin W R et al (1989) Canine phythiosis--isolation and identification of Pythium insidiosum. J Vet Diag Inv 1 (4), 295-298 PubMed.
• Howerth E W, Brown C C, Crowder C (1989) Subcutaneous pythiosis in a dog. J Vet Diag Inv 1 (1), 81-83 PubMed.
• Foil C S O, Short B G, Fadok V A et al (1984) A report of subcutaneous pythiosis​ in five dogs and a review of the etiologic agent Pythium spp. JAAHA 20 (6), 959-966 VetMedResource.