Candidiasis
Introduction
- Caused by Candida spp.
- Noramally present on skin and in GI tract
- Immunocompromised animals may show symptoms
- Usually lesions on mucous membranes and at mucocutaneous junctions
- Grossly:
- Exudative, papular, pustular to ulcerative dermatitis
- Stomatitis and otitis externa may develop
- Microscopically:
- Spongiotic neutrophilic pustular inflammation
- Parakeratosis
- Ulcerations
- Superficial exudate containing organisms
Candidasis in birds
Signalment
The disease is common in neonatal psittacine birds. Immunosuppressive conditions and trauma to the ingluvies lead to the development of candidiasis. Predisposing factors include hypothermia, feeding a formula that is too cold or too hot - causing crop burns, poor nutrition, longterm antibiotic therapy, hypovitaminosis A and systemic illness from other causes.
Clinical Sings
The bird may present with inflammation and delayed emptying of the ingluvies.
Diagnosis
Diagnosis is based on identification of oval yeasts and hyphae on cytological smears taken from swabs and crop washes or aspirates. Wrights stain can be used to demonstrate the yeasts. There should be no evidence of an inflammatory response. The presence of hyphae indicates that the crop may have been penetrated and the infection spread systemically.
Treatment
An antifungal drug is indicated for the treatment of candidiasis. The presence of hyphae is suggestive of invasion of the mucosa by the yeast and the potential for a systemic infection. Therefore, a systemic antifungal – e.g. itraconazole PO for 7 days – should be used along with a local or topical antifungal, e.g. nystatin BID or TID for 7–10 days.
Prognosis
The presence of hyphae on cytological examination suggests a severe infection and potential systemic spread, and therefore a poor prognosis. Without evidence of hyphae the prognosis is improved.
References
Forbes NA & Altman RB (1998) Self-Assessment Colour Review Avian Medicine Manson Publishing Ltd
Girling, S (2004) Diseases of the digestive tract of psittacine birds In Practice 2004 26: 146-15