CHAPTER 49 VIRAL DERMATOSES 715
Immunohistochemistry: immunofluorescent or avidin-biotin complex method
often employed for detection of papillomavirus group-related antigens; requires
active viral replication for detection, leading to possible false-negative results. Electron microscopy:
Highly selective and diagnostic
May be performed on crust, biopsy specimen, or exudate.
THERAPEUTICS
Usually outpatient, except for systemically ill patients.
Systemically ill: may require IV fluids, parenteral antibiotics; supportive care and
treatment of secondary infections.
Azithromycin 10 mg/kg PO q24h for 10–14 days; papillomavirus (questionable effi-
cacy).
L-lysine 200–500 mg/cat PO BID (questionable efficacy).
Famcyclovir 62.5–125 mg/cat PO TID for 3 weeks (lower dose for kittens).
Zidovudine (Retrovir or Retrovis – Glaxo SmithKline): direct antiviral agent, most
effective against acute FIV infections, monitor for bone marrow suppression; 5–
15 mg/kg PO BID (primarily FIV, FeLV).Interferon-alpha: 1000–2000 units q24h orally (immunomodulating dose) or 1–2
million units/m^2 by subcutaneous injection three times weekly.
Topical imiquimod (Aldara): primarily used for Bowen’s syndrome (SCCin situ);
applied 2–3 consecutive days/week.
Topical 5-fluorouracil (0.5%): contraindicated in cats due to neurotoxicity.
Vaccinations as preventive for certain virus infections (e.g., distemper, FeLV).
Immunomodulators with limited success:Proprionibacterium acnes(ImmunoReg-
ulin – Neogen) and acemannan (Carrisyn – Carrington Labs).
Ophthalmic antivirals: vidarabine (Vira-A – Parke-Davis); used for herpetic ulcers
q2h.
Surgical removal of papillomas; surgical excision, cryosurgery, laser surgery.