Retrospective Review of Mycobacterial Conjunctivitis in Cockatiels (Nymphicus hollandicus).

The etiologic disease organism responsible for causing mycobacteriosis in avian species is an acid-fast gram-positive bacterium. This bacterium causes granulomatous disease in various internal organs, but in cockatiels (Nymphicus hollandicus) it has been commonly identified within the conjunctival tissues. Twenty-six cases of mycobacterial conjunctivitis in cockatiels were diagnosed through histopathologic assessment of diseased tissue samples, Fite acid-fast staining, and polymerase chain reaction in this retrospective study. Clinicians who saw these cases were contacted, and information was obtained regarding recommended treatment protocols prescribed for the patients, the Mycobacterium species identified, and case outcomes. All patients in this retrospective study had a biopsy performed on the affected conjunctival tissue, and because of the small size of the patients, this excisional biopsy removed the affected tissue in its entirety or significantly debulked the lesion. Of the 26 cases, 10 were lost to follow-up, 4 were euthanatized, 7 died, and 5 were alive at the time this information was submitted for publication.