[C] 1.63 Granulomas caused by fungi Flashcards
List the diseases caused by microscopical fungi
- Dermatomycosis
- Visceral mycosis
- Primary mycosis of certain organs
- Metastatic mycosis
- Generalised mycosis
- Mycotoxicosis
Give the groups of microscopical fungi causing visceral mycosis
- Blastomyces
- Hyphomycetes
- Phycomyces
Blastomyces
Yeast fungi
- Pseudomyces
- Candida
- Geotrichum
- Cryptococcus
Hyphomyces
Mould fungi
- Septa hyphae
- Penicillium
- Aspergillus
Phycomycetes
Mould fungi
- Real (non-septa)
- Hyphae
- Mucor
- Rhizopus
Fungal terminology: Non-sexual forms of fungi
- Fungal thread = Hyphae
- Cross wall = Septum
- Network of threads = Mycelium
- Colony of fungi = Thallus
Fungi terminology: Sexual forms of fungi
- Conidium = Spores
- Vesicula = Bladder structure
- Germ tube = → Hyphae
Grocott-staining: +++
PAS-reaction: ++
Gram-staining: +++ (Candida spp.)
Grocott-staining: +++
PAS-reaction: ++
Gram-staining: - (+)
Grocott-staining: +++
PAS-reaction: + / -
Gram-staining: -
Changes due to visceral mycosis: In organs
- Granuloma formation
- Proliferative inflammation
- Necrotic inflammatory focus
- Thrombosis, thromboembolia
Changes due to visceral mycosis: On surfaces
Covered by mucous membrane
- Circumscribed necrotic ulcerative inflammation
Mycotic granuloma: In mammals
Epitheloid type
Mycotic granuloma: In birds
Foreign body type
Endogenous factors predisposing for mycosis
- Reduced immunoreactivity
- Injury of the mucosa of the GI & resp. tract
Exogenous factors predisposing for mycosis
- Long term antibiotic treatment
- Cytostatic treatment
- Corticosteroid treatment
Mycotoxicosis
Toxic fungal metabolites
- Several thousand different mycotoxins
- Mainly mixed fungal contamination
- Toxins are of different strength
- Harmful effect of mycotoxins
Give the harmful effects of mycotoxins
Dose-dependent:
- Direct organ damage
- Immunosuppressive effect
- Production loss
- Feed spoilage
Aflatoxins
Aspergillus flavus et parasiticus
- Hepatotoxicity & carcinogenic
- Day-old chick most susceptible
- Swine & Zoonotic
Give the lesions of aflatoxins
- Anaemia
- Fatty liver degeneration
- Bile duct proliferation
- Hepatocellular carcinoma
Ochratoxins
Aspergullus ochraceus
- Kidney & liver damage
- Swine & poultry
- Zoonotic
- Nephropathy & Gout
- Chronic toxicosis
Ergot alkaloids
Claviceps purpurea
- Affects all species
- Vasoconstriction
- Skin necrosis on the extremities
- Abortion & agalactia (low milk)
Zearalenone (F-2 toxin)
Fusarium spp.
- Oestrogen syndrome in swine
- Lesions are dose/age-dependent
- Gilts: Tumefaction of the vulva & vaginitis
- Sows & Gilts: Hormonal imbalance
- Anestrus
- Fatteners & Gilts: Rectal prolapse
- Suckling piglets: Vulvar swelling & teat necrosis
Trichotecen fusariotoxins
Fusarium spp.
- May cause problems in any species
- Necrotic-ulcerative stomatitis
- Haemorrhagic diathesis
- BM damage
- Feed refusal
Macrocyclic trichotecens
Stachybotris chartarum
- Barley/straw
- Black mould
- Horse, cattle, sheep, swine, poultry
- Necrotic ulcerative stomatitis
- Haemorrhagic diathesis
- BM damage
- Superficial necrotic dermatitis
Fumonisins
Fusarium moniliforme - Fumonisin B1
- Swine
- Fattens lung oedema
- Liver dystrophy
- Horse
- Leukoencephalomalatia
- May affect the spinal cord too
- Liver dystrophy
Fungal allergies
Inhalation of fungal spores
- Allergic alveolitis
- Farmers lung - Human & cattle
- Type-III hypersensitivity reaction to mould spores
- Granulomatous inflammation, alveolar epithelial hyperplasia & fibrosis
Give the Mycotoxins
- Aflatoxins
- Ochratoxins
- Ergot alkaloids
- Zearalenone
- Trichotecen fusariotoxins
- Macrocyclic trichotecens
- Fumonisins
