# Disseminated Infection with Aspergillus fumigatus in a Scarlet Macaw Parrot (Ara macao)—A Case Report

## TL;DR

A scarlet macaw parrot died from a widespread fungal infection caused by Aspergillus fumigatus, diagnosed through postmortem examination and molecular testing.

## Contribution

This is the first reported case of disseminated Aspergillus fumigatus infection in a scarlet macaw parrot.

## Key findings

- Postmortem examination revealed granulomas and caseous plaques in multiple organs, including lungs, air sacs, and liver.
- Fungal hyphae were confirmed via histopathology, culture, and molecular identification as Aspergillus fumigatus.
- The case highlights the diagnostic challenges of aspergillosis in psittacine birds due to non-specific clinical signs.

## Abstract

Aspergillosis is an important fungal disease occurring in avian fauna, especially in birds kept in captivity. In Psittaciformes, severe disease occurs in the lungs and air sacs, with the development of white-to-yellow caseous nodules and plaques in the organs, in addition to greenish-grey fungal growth in the air sacs. Herein, we report the presence of disseminated infection with Aspergillus fumigatus in a 3-year-old male scarlet macaw parrot (Ara macao) that was presented to the Exotic Animal Clinic at the Faculty of Veterinary Medicine, Iași University of Life Sciences (Iași, Romania) for its postmortem examination. The confirmation of the fungal infection was achieved using histopathological, microbiological, and molecular methods. Since birds suffering from Aspergillus spp. do not always show respiratory issues, or their clinical signs are non-specific, this may create diagnostic difficulty for clinicians unfamiliar with the parrots’ pathology. Therefore, for a definitive diagnosis, the demonstration of fungal presence by cytology or histopathology and its identification using culturing and molecular techniques is required.

A 3-year-old male scarlet macaw parrot (Ara macao) was presented to the Exotic Animal Clinic at the Faculty of Veterinary Medicine, Iași University of Life Sciences (Iași, Romania) for its postmortem examination. According to the owner, the parrot had been raised only in captivity and after 5 days of inappetence, lethargy, and mild respiratory clinical signs, the parrot died. The post mortem examination revealed various-sized granulomas and caseous plaques in the lungs, air sacs, spleen, intestinal serosa, and liver. Microscopically, the granulomas were characterized by a necrotic center and the infiltration of numerous multinucleated giant cells and epithelioid-like cells and by the presence of hyphae typical of Aspergillus spp. Moreover, in the liver tissue, a diffuse inflammation, with numerous fungal hyphae, was noted. The fungal culture and the PCR assay allowed for the isolation and identification of Aspergillus fumigatus from the lung and liver samples. The macroscopical lesions and the histopathological findings, with the fungal isolation and molecular confirmation of Aspergillus fumigatus by nested PCR, provided the basis for the diagnosis of disseminated aspergillosis. To the authors’ best knowledge, this is the first report of disseminated infection caused by Aspergillus fumigatus in a scarlet macaw parrot (Ara macao).