Therapeutics: non-bacterial infection

Non-bacterial infections

Antifungal agents

Topical agents

• Treatment of fungal infections of skin, ear and eye.

Skin infections

• Successful treatment depends on management which limits infection, eg grooming, clipping, isolation, cleansing agents for animal and environment.
• Systemic agents may be used also.

Dermatophytoses:

• Infections commonly caused by Trichophyton spp , and Microsporum :
  • Enilconazole wash.

Pruritic skin disease

• Seborrhea and otitis externa caused by Malassezia pachydermatis:
  • Enilconazole wash.
  • Ketoconazole * shampoo.

Others

• Povidone-iodine solution.

Ear infections

• Usually combination preparations.

Yeasts

• Nystatin * .
• Miconazole * .

Eye infections

• Conditions may be superficial, eg mycotic keratitis or intra-ocular, eg mycotic endophthalmitis .
• Most topical preparations have poor corneal penetration, so systemic preparations preferred.

Aspergillosis

• For nasal infection with Aspergillus fumigatus : combination treatment with systemic ketoconazole *, surgery and intrasinus treatment using enilconazole * .
• May also treat with intranasally instilled clotrimazole .

Systemic agents

• Griseofulvin .
• For dermatophyte infections.
• Deposited in keratin precursor cells → stratum corneum of skin, hair and nails → prevents fungal invasion of new cells.
• Absorption enhanced by administration with fatty meal.
• Treatment usually minimum 3-4 weeks → 12 weeks.
  May be teratogenic: avoid handling by pregnant women

Imidazoles

• Interfere with biosynthesis of ergosterol.
• Fungistatic.
• Broad spectrum.
• Clotrimazole .
• Topical.
• Malassezia infection (as 1% solution).
• Miconazole .
• Topical.
• Too toxic for treatment of systemic fungal infections.
• Ketoconazole * .
• Active against fungi and yeasts, some gram-positive bacteria.
• For systemic candidiasis and refractory dermatophytoses.
• Administration with food may → nausea. Do not administer with antacids, which can reduce its absorption.
• Interferes with mammalian adrenal and gonadal steroid synthesis → alternative treatment for Cushing's disease (hyperadrenocorticism ).
  
  May be teratogenic; prolonged administration may result in liver damage
• Itraconazole * .
• Systemic candidiasis, refractory dermatophytoses, sytemic fungal infections.
  
  Do not administer with antacids, which can reduce its absorption.
• Fluconazole .
• Systemic candidiasis, refractory dermatophytosis, systemic fungal infections.
• Absorption not affected by antacids.
• Nystatin * .
• Gastrointestinal candidiasis .
• Amphotericin * .
• Against yeasts and fungi. Used for life-threatening or refractory systemic fungal infections.
• Nephrotoxic. Requires saline diuresis. Liposomal formulation markedly reduces nephrotoxicity.

Antiviral agents

• Used mainly in ophthalmology.

Eye infections

• Feline herpesvirus - conjunctivitis and keratitis .
• Aciclovir * .

Antiprotozoal agents

Coccidiosis

• Isospora spp infections.
• Co-trimazine (trimethoprim + sulfadiazine) .

Neosporosis

• Neospora caninum .
• Clindamycin .
• Co-trimazine (trimethoprim + sulfadiazine) - see above, also in combination with pyrimethamine.

Toxoplasmosis

• Clindamycin .
• Co-trimazine (trimethoprim + sulfaziazine) - see above, also in combination with pyrimethamine.

Giardiasis

• Giardia spp .
• Metronidazole .
• Fenbendazole .
• * Indicates not licensed for this use in this species.

Sources

Publications

Refereed papers

• Recent references from PubMed.

Other sources of information

• Lappin M R (2000) Protozoal and miscellaneous infections. In: Textbook of Veterinary Internal Medicine.5th edn. Ettinger S J & Feldman E C (eds). W B Saunders, Philadelphia. pp 408-417.
• Taboada J (2000) Systemic mycoses. In: Textbook of Veterinary Internal Medicine.5th edn. Ettinger S J & Feldman E C (eds). W B Saunders, Philadelphia. pp 453-476.
• Plumb D C (1999) Veterinary Drug Handbook. 3rd edn. Iowa State University Press, Ames, Iowa.