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Created page with "{{unfinished}} ==Taxonomy== *Phylum Microspora; no mitochondria polar tube polar cap *Class Microsporida *Order Microsporidia *May be more related to fungi than to protozoa (Was..."
{{unfinished}}
==Taxonomy==
*Phylum Microspora; no mitochondria polar tube polar cap
*Class Microsporida
*Order Microsporidia
*May be more related to fungi than to protozoa (Wasson and Peper 2000)
*Obligate intracellular protozoan parasite
*52% normal healthy domestic pet rabbits arte infected (Keeble and Shaw 2006)
*Ubiquitous in other species too
==The life cycle==
The life cycle of this coccidian is 3 – 4 weeks in total:
*Inhaled, ingested or transplacental – rabbits of 4 – 6 weeks appear most vulnerable
*In utero infections => invasion of foetal lens => => => => => => multiplication and euption of spores later in the rabbit’s life => cataracts, lens rupture and phacoclastic [[Uveitis – Rabbit|uveitis]]
*Invasion of the mucosa per polar tube
*Spiroplasm extruded and multiplication occurs in vacuole
*Distribution by reticulo-endothelial cells => invasion of organs with high blood flow
*Invasion of target organs
*Intracellular multiplication, cell rupture (=> inflammation) and invasion of neighbouring cells or passage to circulation in 3-4 weeks
*Shedding in urine 35 days after initial infection.
==Presentations of ''Encephalitozoon cuniculi'' in pet rabbits==
*Granulomatous encephalitis, sometimes perivascular infiltration with lymphocytes and plasma cells in all areas of the brain
*Granulomatous nephritis or interstitial infiltration of lymphocytes and plasma cells
**Usually asymptomatic
**Possibly haematuria
**Incontinence could be neurological in origin
**Treat with benzimidazoles and antibiotics
*Pyogranulomatous phacoclastic uveitis
==Transmission of ''Encephalitozoon cuniculi''==
*Shedding in urine
*Oral and tracheal access
*Neonates can be infected but can also receive immunity from dam.
*Ecto- and endo-parasites? May aid in transmission
*Provision of recently cut short grass gathered from the wild
==Pathology==
*Principal target organs are kidney, brain, spinal cord
*Other target organs include liver and heart
*Rupture of host cell => invasion of neighbouring cells => chronic, granulomatous inflammation.
*In utero infections => invasion of foetal lens => => => => => => multiplication and eruption of spores later in the rabbit’s life => cataracts, lens rupture and phacoclastic [[Uveitis – Rabbit|uveitis]]
==Survival of ''Encephalitozoon cuniculi'' in the environment==
*Survives in extreme cold or heat
*At average temperature and in dry conditions it survives 4 weeks
*Easily killed by routine disinfection
==Diagnosis==
*Urine microscopy (35 days after initial infection)
*Serology – antibodies develop soon after infection but clinical signs take much longer (several weeks)
*Antibodies demonstrated 2 weeks before organisms can be demonstrated intracellularly and 4 weeks before histopathological changes are demonstrated in kidney or organisms demonstrated in urine (Harcourt Brown 2002)
*PCR
*CSF analysis
**Procedure:
***Propofol and intubation
***Head flexed 90º to spine
***38mm 22G spinal needle in cisterna magna
***700-1000μl sample.
***Vestibular signs are accentuated for up to 8hrs post sampling.
**Findings
***Lymphomonocytic pleocytosis 15 cells/μl (n=1.5 /μl)
***Increased protein 0.79g/μl (n= 0.24g/μl)
***Unfortunately other viral, protozoan or immune-mediated encephalitis may induce similar lymphomonocytic pleocytosis
==Interpretation of Encephalitozoon antibody tests (Keeble 2007)==
Single positive result in healthy rabbit
*Recent infection prior to development of clinical signs
*Chronically infected with no clinical signs
*Previously infected and recovered
*Antibody levels can persist for many years in symptomless animals
Single positive result in rabbit with clinical signs of encephalitozoonosis
*Could be active Encephalitozoon cuniculi infection (or other infection causing signs)
Single negative result in healthy rabbit
*Could be free from infection
*Could be infected less than 2 weeks ago
*Retest in four weeks
Single negative result in rabbit with clinical signs of encephalitozoonosis
*Rules out Encephalitozoon cuniculi infection as the cause of clinical signs
*Advise further tests
**renal biopsy
**CSF analysis
**mononulear pleocytosis and elevated protein
**MRI/CT scans
To establish an Encephalitozoon-free colony:
*Test fortnightly for two months or until all animals are negative for a month, whichever is longer
*Sacrifice any positive cases
Treatment
*Albendazole 10 mg/kg q 24 hrs - ?teratogenic (Pollock 2006)
*Fenbendazole 20 mg/kg q 24 hrs
*Oxytetracycline 30 mg/kg SC q 72hrs.
*Three possible therapies – my cocktail is albendazole and oxytetracycline as shown above.
*Vestibular-calming agents
*Environmental disinfection
*Corticosteroids
==Taxonomy==
*Phylum Microspora; no mitochondria polar tube polar cap
*Class Microsporida
*Order Microsporidia
*May be more related to fungi than to protozoa (Wasson and Peper 2000)
*Obligate intracellular protozoan parasite
*52% normal healthy domestic pet rabbits arte infected (Keeble and Shaw 2006)
*Ubiquitous in other species too
==The life cycle==
The life cycle of this coccidian is 3 – 4 weeks in total:
*Inhaled, ingested or transplacental – rabbits of 4 – 6 weeks appear most vulnerable
*In utero infections => invasion of foetal lens => => => => => => multiplication and euption of spores later in the rabbit’s life => cataracts, lens rupture and phacoclastic [[Uveitis – Rabbit|uveitis]]
*Invasion of the mucosa per polar tube
*Spiroplasm extruded and multiplication occurs in vacuole
*Distribution by reticulo-endothelial cells => invasion of organs with high blood flow
*Invasion of target organs
*Intracellular multiplication, cell rupture (=> inflammation) and invasion of neighbouring cells or passage to circulation in 3-4 weeks
*Shedding in urine 35 days after initial infection.
==Presentations of ''Encephalitozoon cuniculi'' in pet rabbits==
*Granulomatous encephalitis, sometimes perivascular infiltration with lymphocytes and plasma cells in all areas of the brain
*Granulomatous nephritis or interstitial infiltration of lymphocytes and plasma cells
**Usually asymptomatic
**Possibly haematuria
**Incontinence could be neurological in origin
**Treat with benzimidazoles and antibiotics
*Pyogranulomatous phacoclastic uveitis
==Transmission of ''Encephalitozoon cuniculi''==
*Shedding in urine
*Oral and tracheal access
*Neonates can be infected but can also receive immunity from dam.
*Ecto- and endo-parasites? May aid in transmission
*Provision of recently cut short grass gathered from the wild
==Pathology==
*Principal target organs are kidney, brain, spinal cord
*Other target organs include liver and heart
*Rupture of host cell => invasion of neighbouring cells => chronic, granulomatous inflammation.
*In utero infections => invasion of foetal lens => => => => => => multiplication and eruption of spores later in the rabbit’s life => cataracts, lens rupture and phacoclastic [[Uveitis – Rabbit|uveitis]]
==Survival of ''Encephalitozoon cuniculi'' in the environment==
*Survives in extreme cold or heat
*At average temperature and in dry conditions it survives 4 weeks
*Easily killed by routine disinfection
==Diagnosis==
*Urine microscopy (35 days after initial infection)
*Serology – antibodies develop soon after infection but clinical signs take much longer (several weeks)
*Antibodies demonstrated 2 weeks before organisms can be demonstrated intracellularly and 4 weeks before histopathological changes are demonstrated in kidney or organisms demonstrated in urine (Harcourt Brown 2002)
*PCR
*CSF analysis
**Procedure:
***Propofol and intubation
***Head flexed 90º to spine
***38mm 22G spinal needle in cisterna magna
***700-1000μl sample.
***Vestibular signs are accentuated for up to 8hrs post sampling.
**Findings
***Lymphomonocytic pleocytosis 15 cells/μl (n=1.5 /μl)
***Increased protein 0.79g/μl (n= 0.24g/μl)
***Unfortunately other viral, protozoan or immune-mediated encephalitis may induce similar lymphomonocytic pleocytosis
==Interpretation of Encephalitozoon antibody tests (Keeble 2007)==
Single positive result in healthy rabbit
*Recent infection prior to development of clinical signs
*Chronically infected with no clinical signs
*Previously infected and recovered
*Antibody levels can persist for many years in symptomless animals
Single positive result in rabbit with clinical signs of encephalitozoonosis
*Could be active Encephalitozoon cuniculi infection (or other infection causing signs)
Single negative result in healthy rabbit
*Could be free from infection
*Could be infected less than 2 weeks ago
*Retest in four weeks
Single negative result in rabbit with clinical signs of encephalitozoonosis
*Rules out Encephalitozoon cuniculi infection as the cause of clinical signs
*Advise further tests
**renal biopsy
**CSF analysis
**mononulear pleocytosis and elevated protein
**MRI/CT scans
To establish an Encephalitozoon-free colony:
*Test fortnightly for two months or until all animals are negative for a month, whichever is longer
*Sacrifice any positive cases
Treatment
*Albendazole 10 mg/kg q 24 hrs - ?teratogenic (Pollock 2006)
*Fenbendazole 20 mg/kg q 24 hrs
*Oxytetracycline 30 mg/kg SC q 72hrs.
*Three possible therapies – my cocktail is albendazole and oxytetracycline as shown above.
*Vestibular-calming agents
*Environmental disinfection
*Corticosteroids