Difference between revisions of "Demodicosis"
Jump to navigation
Jump to search
| Line 34: | Line 34: | ||
*To aid [[Ectoparasiticides|acaricide]] penetration, clipping a dog's coat and washing is recommended | *To aid [[Ectoparasiticides|acaricide]] penetration, clipping a dog's coat and washing is recommended | ||
| + | |||
| + | ===From Pathology== | ||
*[[Demodex|''Demodex'']] are normal inhabitants of hair follicles and sebaceous glands | *[[Demodex|''Demodex'']] are normal inhabitants of hair follicles and sebaceous glands | ||
Revision as of 10:29, 30 June 2010
Caused by Demodex
Pathogenesis and epidemiology
- Squamous demodecosis
- Less serious
- Dry reaction
- Alopecia, desquamation and skin thickening
- Absent to mild pruritus
- Follicular/pustular demodecosis
- More serious
- Skin invasion by staphylococci
- Skin becomes wrinkled, thickened and contains pustules which ooze serum, blood or pus
- Affected animals may be seriously disfigured
- Severe pruritus is associated with secondary infection
- Immune factors are important in determining the severity and occurrence of demodecosis
- Familial susceptibility
- Immunosuppression
- Immunosuppressant therapy
Diagnosis
- Liquid paraffin applied to a skin fold
- Deep skin scraping
Control
- Not easily accessible to acaricides due to their deep location in the skin
- Repeat treatments needed
- Recovery may take several months
- To aid acaricide penetration, clipping a dog's coat and washing is recommended
=From Pathology
- Demodex are normal inhabitants of hair follicles and sebaceous glands
- Have to have increased number of immature mites to classify as infestation
- Host-specific
- Occurs in dogs, cattle, sheep, goats, pigs, horses and cats
- Transmits during nursing from dam to offspring
- Demodex canis in dogs:
- Generalised or localised
- Mainly young dogs affected or adults with other disease (hyperadrenocorticism, hypothyroidism)
- Often inherited in pure bred
- Grossly:
- Localised: scaly, erythematous, macular, alopecic areas; usually face or front legs
- Generalised: large, coalescing lesions, patches, erythema, alopecia, scales, crusts
- Microscopically:
- Localised: lymphoplasmacytic perifolliculitis with hyperkeratinisation, sebaceous adenitis, low pigment, intraluminal mites
- Generalised: perifolliculitis and follicular hyperkeratosis, follicular pluggingf, bacterial proliferation, bacterial neutrophilic folliculitis
- May cause folliculat rupture -> furunculosis, cellulitis, lymphadenitis and septicaemia