246 DISEASES/DISORDERS
Tick Bite Dermatitis and Hypersensitivity
Presence of attached ticks.
Biopsy: leukocytoclastic vasculitis, epidermal hemorrhage and necrosis, eosinophil-
rich pyogranulomatous dermatitis.
Diagnostic testing for tick-vectored diseases.
Hymenoptera
Biopsy: intraepidermal neutrophilic pustule with superficial and deep dermal inter-
stitial neutrophilic dermatitis and collagen degeneration.
Presence of stinger(s) or adherent ants.
History of exposure.
Intradermal allergy testing with hymenoptera antigens.
THERAPEUTICS
Flea Bite Dermatitis and Hypersensitivity
Flea control:
All dogs and cats in the household must be treated
Flea control measures should be tailored to the individual situation
Multiple effective products are available including spot-ons, sprays, collars, and
systemic medications
Client education is required for successful control of fleas both on the pet andin the environment.
Topical corticosteroid sprays (with or without antibiotics) effective for individual
lesions.
Prednisolone (2–4 mg/kg q24h tapering dosage).
Antibiotics only for pyotraumatic folliculitis (“deep” hotspot).
Antihistamines rarely effective for complete control of symptoms.
Spider Bite Dermatitis
Local infusion of early lesions with corticosteroids and/or lidocaine.
Systemic support with antibiotics, antiinflammatory medications, and analgesics.
Wound treatment.
Environmental clean-up (eliminating outdoor sites and insecticide spraying).
Fly Dermatitis
Fly avoidance.
Application of repellants to pinnae.
Wound treatment.
Environmental clean-up to remove fly breeding sources.