Flea Allergy Dermatitis Flashcards
What is the most common flea that infects dogs and cats? What 3 pathogens can they carry?
Ctenocephalides felis felis
- Dipylidium caninum
- Bartonella henselae
- Yersinia pestis
What are the 4 steps to the life cycle of fleas? How long is the average life cycle?
- adult
- egg
- larva
- pupa
3 weeks –> can take months if conditions are not met
What 2 dermatological conditions can fleas cause?
- infestation - skin disease with mild to moderate pruritus caused by flea bites
- flea allergy dermatitis - reaction to salivary enzymes containing proteolytic enzymes, histamine-like compounds, anti-coagulants, happens, and antigens
What 3 hypersensitivities are associated with flea allergy dermatitis?
- Type 1 - IgE
- Type 4 - delayed cellular response
- basophil hypersensitivity
What lesions are associated with flea allergy dermatitis?
- erythema
- alopecia
- papules, pustules
- excoriations
- crusts
- moist dermatitis
- CHRONIC = hyperpigmentation, lichenification
++++ PRURITUS
How does the distribution of flea allergy dermatitis lesions compare in dogs and cats?
DOGS - caudal dorsal, base of tail, posterior/lateral aspect of rear legs, ventral abdomen
CATS - neck and face, military dermatitis and eosinophilic granuloma complex, symmetrical alopecia dorsolaterally
Flea allergy dermatitis, dog:
- caudal dorsal
- base of tail
- posterior/lateral aspect of rear legs
- ventral abdomen
How can the presence of fleas be tested in possible cases of flea allergy dermatitis?
use a wet paper towel to collect potential fleas and their excrement –> digested blood in the flea dirt should dissolve with water and cause a reddish hue on the paper towel
majority of FAD patients will NOT have fleas or flea dirt
What are the 3 symptomatic/palliative therapies recommended for flea allergy dermatitis?
- short-term glucocorticoids
- antihistamines
- Apoquel or Cytopoint
What are 2 important parts to the approach of flea control? How long does this take?
- treat each animal in the house
- treat the home environment to eliminate the environmental reservoir
2-3 months - average time in the pupa stage is 1-2 months, which is when the flea is most resistant to environmental treatments
How are adulticides used to treat flea allergy dermatitis? How quick do they tend to work?
eliminates present fleas, but does not prevent re-infection
minutes to 48 hours - depends on concentration, use products that kill before eggs are laid
What are 2 types of repellents used against fleas?
- vapor phase - DEET, citrus oil (affect unclear in animals)
- physical contact - Permethrin
How do insect growth regulators work? What are the 2 most common categories?
disrupt developmental process
- juvenile hormone analogues - mimics hormones and prevent progression through juvenile stage (Methoprene (UV light sensitive), Pyriproxifen (UV light stable))
- insect development inhibitors - disrupts formation of cuticle, mouthparts, egg teeth, and other chitinous structures (Lufenuron)
What are some flea adulticides used in small animals? Which is toxic to rabbits? Which cannot be used with Ivermectin?
- Afoxalaner
- Dinotefuron
- Etofenprox
- Flumethrin
- Fluralaner
- Imidacloprid
- Indoxacarb
- Nitenpyram
- Selamectin
- Spinetoram
Fipronil
Spinosad - caution in neurological patients
What are 4 flea adulticides that are also repellants?
- Cyphenorthrin
- Deltamethrin
- Permethrin (toxic to cats!)
- Pyrethrin
(Amitraz = repellant only)
