Difference between revisions of "Subcutaneous Mycoses"

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#REDIRECT[[:Category:Subcutaneous Mycoses]]
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 +
==Chromoblastomycosis==
 +
 
 +
*Occurs in horses, dogs, cats and himans
 +
 
 +
*Caused by [[Dermatophytosis|dematiaceous fungi]]:
 +
**''Exophilia jeanselmeri, Phialophora, Cladosporium carrionii, Fonsecaea pedrosoi''
 +
 
 +
*Enters tissue through wounds or sites of tissue trauma
 +
**Limited to subcutaneous and cutaneous tissues
 +
 
 +
*Causes hyperplasia and formation of verrucoid, warty nodules
 +
**Warts are irregular, vegetative and pedunculated
 +
 
 +
*Spread is via the [[Lymphatic System - Anatomy & Physiology|lymphatic system]]
 +
**Dissemination to other tissues and organs can occur
 +
 
 +
*Chronic condition which will progress if not treated
 +
 
 +
*Treatment includes [[Antifungal Drugs#The Azoles|Ketoconazole]], [[Antifungal Drugs#Flucytosine|5-fluorocytosine]] and [[Antifungal Drugs#Polyene Antifungals|amphotericin B]]
 +
 
 +
==Chromomycosis==
 +
 
 +
*Also called Phaeohyphomycosis
 +
 
 +
*Opportunistic
 +
 
 +
*Infects horses, dogs and humans
 +
**Found in wounds and abrasions
 +
 
 +
*Caused by [[Dermatophytosis|dematiaceous fungi]]
 +
**''Dactylaria gallopava, Exophiala pisciphila, E. salmonis, Scolecobasidium humicola, S. tshawytschae, Drechslera, Exophilia jeanselmeri, E. verrucosa, Fonsecaea pelrosoi''
 +
 
 +
*Nodular and ulcerating lesions of the skin on the feet, legs and occasionally eyes (in turkeys)
 +
**Regional granulomatous lymphadenitis
 +
 
 +
*Single cells or clusters, spherical and thick-walled
 +
*Brown pigmented fungal elements
 +
 
 +
*Multiply by cross-wall formation or splitting (not budding)
 +
 
 +
*Grows on Sabauraud's Dextrose agar ar room temperature
 +
**Slow growth
 +
**Takes one month
 +
 
 +
*For further information, see [[Dermatophytosis|dematiaceous fungi]]
 +
 
 +
==Epizootic Lymphangitis==
 +
 
 +
*''Histoplasma capsulatum'' var. ''farciminosum''
 +
**Similar to ''H. capsulatum''
 +
 
 +
*Occurs in horses, donkeys and mules
 +
*90% occurs in horses
 +
 
 +
*Occurs in Europe, Africa and Asia
 +
**Eradicated from the UK but is still under the notifiable Diseases of Animals Act
 +
 
 +
*Chronic disease
 +
 
 +
*Highly contageous
 +
**Spread by direct contact or indirect, e.g. through infected grooming equipment, [[Biting Flies|biting flies]]
 +
 
 +
*Once established in a population it is very difficult to eradicate
 +
**Long incubation peroid
 +
**New cases can develop weeks or months after the infection appears to have been eradicated
 +
 
 +
*Affects the [[Lymph Nodes - Anatomy & Physiology|lymph nodes]], [[Lymphatic Vessels - Anatomy & Physiology|lymph vessels]] and [[Skin - Anatomy & Physiology|skin]]
 +
**Mostly of the [[Musculoskeletal System - Anatomy & Physiology#The Head and Neck|neck]] and [[Musculoskeletal System - Anatomy & Physiology#Limbs of the Domestic Species|limbs]]
 +
 
 +
*Causes ulcerative, nodular lesions
 +
**Dissemination occurs
 +
**Pulmonary disease can occur
 +
**Ulcers rupture, discharging blood-stained pus for several weeks
 +
 
 +
*Oval or pear shaped cells
 +
**Double contoured
 +
**Dimorphic
 +
***Grows in the yeast phase at 37°C and in the mycelial phase at room temperature
 +
**Growth is slow, taking up to 8 weeks
 +
**At room temperature, thick-walled chlamydospores can be seen
 +
**Orgnaisms can usually be seen in swollen [[Leukocytes - WikiBlood|leucocytes]]
 +
 
 +
*Can be stained using Gram, Giemsa, H & E and 10% Methylene Blue followed by Carbol Fuchsin
 +
 
 +
*Enzyme-linked immunosorbant assay can be used to detect the fungi
 +
 
 +
*Life-long immunity follows recovery from infection
 +
 
 +
*Treatment included potassium iodide, [[Antifungal Drugs#Polyene Antifungals|hamycin]] and [[Antifungal Drugs#Polyene Antifungals|Amphotericin B]]
 +
**Vaccination has also proven to be effective
 +
**Injection of hyperimmune serum around skin lesions has been proven to be effective
 +
 
 +
==Eumycotic Mycetoma==
 +
 
 +
*''Pseudoallescheria boydii, Curvularia geniculata, Cochliobolus spicifer, Helminthosporium'' spp.
 +
 
 +
*Lives in soil
 +
 
 +
*Enters the body via wounds
 +
 
 +
*Granulomatous abscesses
 +
 
 +
*Microcolonies can be seen grossly in exudate or lesions
 +
**Grains or granules
 +
**Brown or black embedded in granulation tissue
 +
**Small, irregularly shaped
 +
 
 +
*Infrequent infections of dogs, cats, cattle and horses
 +
 
 +
*Usually affect the extremities
 +
**Can infect the [[Nasal cavity - Anatomy & Physiology|nasal mucosa]]
 +
***E.g. Bovine nasal granuloma
 +
**Can also infect the peritoneum and [[Skin - Anatomy & Physiology|skin]]
 +
 
 +
*Microscopically:
 +
**Grains of maduromycosis with wide mycelia (compared to actinomycotic granules)
 +
**Chlamydospores present
 +
 
 +
*Grows on Sabauraud's Dextrose agar
 +
**Slow
 +
**Takes 2-3 weeks
 +
 
 +
*Treatment includes [[Antifungal Drugs#The Azoles|Ketoconazole]], [[Antifungal Drugs#Flucytosine|5-fluorocytosine]] and [[Antifungal Drugs#Polyene Antifungals|amphotericin B]]
 +
 
 +
==Hyphomycosis==
 +
 
 +
*''Hyphomyces destruens''
 +
 
 +
*Opportunistic infection
 +
**Associated with trauma
 +
 
 +
*Rare
 +
 
 +
*Caused by ''Penicillium, Beauveria, Acremonium, Fusarium, Paecilomyces''
 +
 
 +
*Infects both animals and humans
 +
**Mainly affects horses
 +
 
 +
*Tropical and semi-tropical countries
 +
 
 +
*Progressive disease causing granulating and ulcerating lesions on the legs and lower body
 +
**Lesions grow rapidly
 +
**Cause extreme debility
 +
 
 +
*Occurs in water
 +
**Most often seen in ponies with access to ponds
 +
 
 +
*Chemotactically attracted to horse hair
 +
 
 +
*Does not respond well to treatment
 +
**Radical surgical excision the best method
 +
**Experiemental vaccination treatment is currently underway and has shown promising results
 +
 
 +
==Pythiosis==
 +
 
 +
*Causes Mycotic Swamp Fever
 +
 
 +
*Also called phycomycosis
 +
 
 +
*Occurs in the USA, Australia, New Guinea, India, Brazil, Colombia, Japan, Costa Rica and Indonesia
 +
 
 +
*''Pythium insidiosum''
 +
 
 +
*Enters via wounds
 +
**[[Lips - Anatomy & Physiology|Lips]], [[Musculoskeletal System - Anatomy & Physiology#The Head and Neck|head]], [[Musculoskeletal System - Anatomy & Physiology#The Head and Neck|neck]], fetlock, hock and [[Hoof - Anatomy & Physiology|hoof]]
 +
 
 +
*Granulomatous infection
 +
**Necrosis and fistulous tracts
 +
**Yellow lesions
 +
 
 +
*Branching, separated fungi
 +
 
 +
*Progressive (rather than systemic) disease
 +
 
 +
*Surgery is needed
 +
 
 +
==Rhinosporidiosis==
 +
 
 +
*''Rhinosporidium seeberi''
 +
 
 +
*Lives in water
 +
 
 +
*Causes a chronic, benign disease
 +
 
 +
*Affects cattle, mules, horses, dogs and humans
 +
 
 +
*Causes polyps on the [[Nasal cavity - Anatomy & Physiology|nasal]] and [[Eye - Anatomy & Physiology|ocular]] mucous membranes
 +
**Over 90% of cases affecting the [[Nasal cavity - Anatomy & Physiology|nasal]] mucous membranes affects male animals
 +
 
 +
*Occurs most frequently in tropical countries
 +
**Also common in the USA
 +
 
 +
*Large sporangia can be seen on wet mounts
 +
**Endospores visible
 +
**Sporangia develop into small, globose spores
 +
 
 +
*Treatment is by surgical excision
 +
 
 +
==Sporotrichosis==
 +
[[Image:Sporotrichosis horse.jpg|thumb|right|150px|Sporotrichosis in a horse -Copyright Professor Andrew N. Rycroft, BSc, PHD, C. Biol.F.I.Biol., FRCPath]]
 +
[[Image:Sporotrichosis cigar cells.jpg|thumb|right|150px|Sporotrichosis cigar shaped cells -Copyright Professor Andrew N. Rycroft, BSc, PHD, C. Biol.F.I.Biol., FRCPath]]
 +
*''Sporothrix schenckii''
 +
 
 +
*Occurs in soil, wood and vegetation
 +
**Saprophyte of both decaying and healthy vegetation
 +
 
 +
*Worldwide
 +
 
 +
*Exogenous infections through wounds
 +
 
 +
*Sporadic infections
 +
 
 +
*Non-contageous
 +
 
 +
*Causes subcutaneous nodules or granulomas
 +
**Nodules ulcerate discharging pus
 +
 
 +
*Spread via the [[Lymphatic System - Anatomy & Physiology|lymphatics]]
 +
 
 +
*The [[Bones and Cartilage - Anatomy & Physiology|bones]] and viscera can be involved which terminates in mortality
 +
**This is rare
 +
**Reported in dogs and horses
 +
 
 +
*Affects dogs, horses, cats, monkeys, mules, camels, donkeys, cattle, fowl and rodents
 +
**Most commonly seen in horses as an ascending lymphocutaneous infection of the legs
 +
**Can be confused with [[Subcutaneous Mycoses#Epizootic Lymphangitis|epizootic lymphangitis]] in horses
 +
 
 +
*Single cell, cigar shaped
 +
**Usually found within [[Neutrophils - WikiBlood|neutrophils]]
 +
**Yeast cell clusters with peripheral eosinophilic rays can be seen in tissue sections
 +
 
 +
*Stained using PAS, Gram stain (positive), fluorescent antibody and Calcofluor White
 +
 
 +
*Latex agglutination and immunodiffusion serology can be performed
 +
 
 +
*Grows on Blood agar and Sabouraud's Dextrose agar in one to three weeks
 +
**At 37°C:
 +
***Colonies are smooth, cream to tan coloured and soft
 +
***No mycelium can be seen
 +
**At 25°C to 27°C:
 +
***Colonies turn from white and soft to tan to brown to black
 +
***Leathery, wrinkled and coarse
 +
***Mycelium can be seen as branching septate hyphae
 +
***Conidiospores can also be seen
 +
 
 +
*Potassium iodide treatment orally
 +
**[[Antifungal Drugs#Flucytosine|5-fluorocytosine]] and [[Antifungal Drugs#Polyene Antifungals|amphotericin B]] can also be used
 +
 
 +
==Further Links==
 +
*Pathology of [[Mycotic skin infections - Pathology#Subcutaneous mycoses|subcutaneous mycoses]]
 +
 
 +
*[[Antifungal Drugs]]

Revision as of 14:44, 14 August 2009



Infectious agents and parasitesWikiBugs Banner.png
FUNGI



Chromoblastomycosis

  • Occurs in horses, dogs, cats and himans
  • Caused by dematiaceous fungi:
    • Exophilia jeanselmeri, Phialophora, Cladosporium carrionii, Fonsecaea pedrosoi
  • Enters tissue through wounds or sites of tissue trauma
    • Limited to subcutaneous and cutaneous tissues
  • Causes hyperplasia and formation of verrucoid, warty nodules
    • Warts are irregular, vegetative and pedunculated
  • Spread is via the lymphatic system
    • Dissemination to other tissues and organs can occur
  • Chronic condition which will progress if not treated

Chromomycosis

  • Also called Phaeohyphomycosis
  • Opportunistic
  • Infects horses, dogs and humans
    • Found in wounds and abrasions
  • Caused by dematiaceous fungi
    • Dactylaria gallopava, Exophiala pisciphila, E. salmonis, Scolecobasidium humicola, S. tshawytschae, Drechslera, Exophilia jeanselmeri, E. verrucosa, Fonsecaea pelrosoi
  • Nodular and ulcerating lesions of the skin on the feet, legs and occasionally eyes (in turkeys)
    • Regional granulomatous lymphadenitis
  • Single cells or clusters, spherical and thick-walled
  • Brown pigmented fungal elements
  • Multiply by cross-wall formation or splitting (not budding)
  • Grows on Sabauraud's Dextrose agar ar room temperature
    • Slow growth
    • Takes one month

Epizootic Lymphangitis

  • Histoplasma capsulatum var. farciminosum
    • Similar to H. capsulatum
  • Occurs in horses, donkeys and mules
  • 90% occurs in horses
  • Occurs in Europe, Africa and Asia
    • Eradicated from the UK but is still under the notifiable Diseases of Animals Act
  • Chronic disease
  • Highly contageous
    • Spread by direct contact or indirect, e.g. through infected grooming equipment, biting flies
  • Once established in a population it is very difficult to eradicate
    • Long incubation peroid
    • New cases can develop weeks or months after the infection appears to have been eradicated
  • Causes ulcerative, nodular lesions
    • Dissemination occurs
    • Pulmonary disease can occur
    • Ulcers rupture, discharging blood-stained pus for several weeks
  • Oval or pear shaped cells
    • Double contoured
    • Dimorphic
      • Grows in the yeast phase at 37°C and in the mycelial phase at room temperature
    • Growth is slow, taking up to 8 weeks
    • At room temperature, thick-walled chlamydospores can be seen
    • Orgnaisms can usually be seen in swollen leucocytes
  • Can be stained using Gram, Giemsa, H & E and 10% Methylene Blue followed by Carbol Fuchsin
  • Enzyme-linked immunosorbant assay can be used to detect the fungi
  • Life-long immunity follows recovery from infection
  • Treatment included potassium iodide, hamycin and Amphotericin B
    • Vaccination has also proven to be effective
    • Injection of hyperimmune serum around skin lesions has been proven to be effective

Eumycotic Mycetoma

  • Pseudoallescheria boydii, Curvularia geniculata, Cochliobolus spicifer, Helminthosporium spp.
  • Lives in soil
  • Enters the body via wounds
  • Granulomatous abscesses
  • Microcolonies can be seen grossly in exudate or lesions
    • Grains or granules
    • Brown or black embedded in granulation tissue
    • Small, irregularly shaped
  • Infrequent infections of dogs, cats, cattle and horses
  • Usually affect the extremities
    • Can infect the nasal mucosa
      • E.g. Bovine nasal granuloma
    • Can also infect the peritoneum and skin
  • Microscopically:
    • Grains of maduromycosis with wide mycelia (compared to actinomycotic granules)
    • Chlamydospores present
  • Grows on Sabauraud's Dextrose agar
    • Slow
    • Takes 2-3 weeks

Hyphomycosis

  • Hyphomyces destruens
  • Opportunistic infection
    • Associated with trauma
  • Rare
  • Caused by Penicillium, Beauveria, Acremonium, Fusarium, Paecilomyces
  • Infects both animals and humans
    • Mainly affects horses
  • Tropical and semi-tropical countries
  • Progressive disease causing granulating and ulcerating lesions on the legs and lower body
    • Lesions grow rapidly
    • Cause extreme debility
  • Occurs in water
    • Most often seen in ponies with access to ponds
  • Chemotactically attracted to horse hair
  • Does not respond well to treatment
    • Radical surgical excision the best method
    • Experiemental vaccination treatment is currently underway and has shown promising results

Pythiosis

  • Causes Mycotic Swamp Fever
  • Also called phycomycosis
  • Occurs in the USA, Australia, New Guinea, India, Brazil, Colombia, Japan, Costa Rica and Indonesia
  • Pythium insidiosum
  • Granulomatous infection
    • Necrosis and fistulous tracts
    • Yellow lesions
  • Branching, separated fungi
  • Progressive (rather than systemic) disease
  • Surgery is needed

Rhinosporidiosis

  • Rhinosporidium seeberi
  • Lives in water
  • Causes a chronic, benign disease
  • Affects cattle, mules, horses, dogs and humans
  • Causes polyps on the nasal and ocular mucous membranes
    • Over 90% of cases affecting the nasal mucous membranes affects male animals
  • Occurs most frequently in tropical countries
    • Also common in the USA
  • Large sporangia can be seen on wet mounts
    • Endospores visible
    • Sporangia develop into small, globose spores
  • Treatment is by surgical excision

Sporotrichosis

Sporotrichosis in a horse -Copyright Professor Andrew N. Rycroft, BSc, PHD, C. Biol.F.I.Biol., FRCPath
Sporotrichosis cigar shaped cells -Copyright Professor Andrew N. Rycroft, BSc, PHD, C. Biol.F.I.Biol., FRCPath
  • Sporothrix schenckii
  • Occurs in soil, wood and vegetation
    • Saprophyte of both decaying and healthy vegetation
  • Worldwide
  • Exogenous infections through wounds
  • Sporadic infections
  • Non-contageous
  • Causes subcutaneous nodules or granulomas
    • Nodules ulcerate discharging pus
  • The bones and viscera can be involved which terminates in mortality
    • This is rare
    • Reported in dogs and horses
  • Affects dogs, horses, cats, monkeys, mules, camels, donkeys, cattle, fowl and rodents
    • Most commonly seen in horses as an ascending lymphocutaneous infection of the legs
    • Can be confused with epizootic lymphangitis in horses
  • Single cell, cigar shaped
    • Usually found within neutrophils
    • Yeast cell clusters with peripheral eosinophilic rays can be seen in tissue sections
  • Stained using PAS, Gram stain (positive), fluorescent antibody and Calcofluor White
  • Latex agglutination and immunodiffusion serology can be performed
  • Grows on Blood agar and Sabouraud's Dextrose agar in one to three weeks
    • At 37°C:
      • Colonies are smooth, cream to tan coloured and soft
      • No mycelium can be seen
    • At 25°C to 27°C:
      • Colonies turn from white and soft to tan to brown to black
      • Leathery, wrinkled and coarse
      • Mycelium can be seen as branching septate hyphae
      • Conidiospores can also be seen

Further Links