LEC 6 - Opportunistic Fungal Infections Flashcards
What is an important step in the life cycle of Phyium insidiosum?
Needs to infect plants to complete cycle
What allows P. Insidiosum to invade animal tissue?
Motile zoospores w/ germ tube production
Affected Animals: P. Insidiosum
Horses Dogs Calves Sheep Cats
Lesions: P. Insidiosum
Granulomatous tissues - Subcutaneous or Intestinal
Infective stage: P. Insidiosum
Animal wades in water
Zoospore infects = oppurtunistic
How doe the zoospores of P. Insidiosum invade the tissue?
Through the germ tubes that produce aseptate hyphae
What does P. Insidiosum do while its disseminating?
Causes thrombosis
What causes tissue damage with P. Insidiosum infections?
Degranulating EOS + Mast cells
Where do lesions in horses tend to occur with P. Insidiosum infections?
Body parts that contacted the water
Disease: P. Insidiosum
Cutaneous pythiosis
Lession appearance: P. Insidiosum in Horse
Large, circular granulomatous nodules
Ulcerate
Pruritus
Necrotic yellowish coral-like mass
What can happen with chronic P. Insidiosum infections?
Bone involvement
Define: Enteric pythioss
Stenotic fibrous GI lesions
Target Organs: P. Insidiosum in DOgs
Stomach + SI
Clinical Signs: P. Insidiosum in Dogs
Vomiting
Wt. Loss
Diarrhea
PALPABLE ABDOMINAL MASS
What is causing the abdominal mass in a dog with a P. Insidiosum infection?
Extension into pancreas + bile ducts + mesenteric LN
Where do cutaneous lesions in dogs tend to occur with P. Insidiosum infections?
Base of tail
Extremities
Perineum
Ventral Neck
Diagnosis: P. Insidiosum
Tissue stain Immunofluorescence PCR Culture Serology
Culture: P. Insidiosum
Sabouraud dex. agar
ID colony: P. Insidiosum
Aseptate hyphae
Colorless to white w/ short aerial hyphae
Stain: P. Insidiosum
PAS + Methenamine silver
P. Insidiosum: Treatment Dogs
Aggressive surgery
Remove infected bowl
Amputate distal limbs infected
NO ERGOSTEROL IN MEMBRANE - still txt w/ Itraconazole
P. Insidiosum: Treament Horses
Wide surgical excision + Immunotherapy
Describe: P. Insidiosum Immunotherapy
Regulation of T cells from Th1 to Th2
Describe P. Insidiosum Thermotherapy
Apply local heat daily to lesion
Enhances intracellular killing capability of NEU
Morphology: Sporothrix schenickii
Dimorphic temperature dependent fungus
Etiology: S. Schenickii
Worldwide
Culture for Environmental form :S. Schenickii
SDA
Colony: S. Schenickii
Hyphae + Condiophores w/ rosette clusters of pear shapped conidia
Environmental form: S. Schenickii
25 deg
Hyphae + Condiphores
Infective form: S. Schenickii
37 deg
Cigar-shapped pleomorphic budding yeast cells
Culture for Infective form: S. Schenickii
Brain Heart Infusion Agar `
Clinical Signs: S. Schenickii = Horse/Dogs
Cutaneous/Lymphocytaneous form
Clincal Signs: S. Schenickii = Cats
Lymphocutaneous
Disseminated
Describe: Equine Sporotrichosis
Lymphocutaneous
Spores enter skin abrasion
Nodules develope along superficial lymphatic vessesl
Describe Feline Sporotrichosis
Primary nodular lesions
Ulcerative with seropurulent exudate
Extends to lymphatics
Areas of infection: S. Schenickii - Felines
Limb extermities
Head
Tail
Area most infected with S. Schenickii in cats
Brazial
Describe Canine Sporotrichosis
Multiple cutaneous lesions
Ulcerated + Crusted + Alopecic
Occasional lymphocutaneous involvement
Treatement: S. Schenickii Horse
Systemic Isodid preparation
Organic perferred (EDDI)
Feed additive
Treatment: S. Schenickii - Dogs/Cats
Itraconazole
Infection form: P. Carinii
Asexual trophozoite
Reproducing form: P. Carinii
Sexual reproducing cyst
Predisposition: P. Carinii
High prevalence of young animals
Airborne/transplacental
Animals infected: P. Carinii
Dogs Horses Rabbits Cats Pigs
DOC: P. Carinii
Trimethoprim
– or –
TMS
Supportive care
Culture: P. Carinii
CAN NOT BE
PCR: P. Carinii where from?
lung tissue
Clincal signs: P. Carinii
Diffuse Pulmonary consolidation
Marked thickening alveolar space
Proteinaceous exudate in alveoli