Hyacinth Macaw, Calvarium. Two oval perforations are present in the temporal bones. The macroscopic reddish-brown foci previously observed in the cerebral cortex corresponded to areas of hemorrhage and malacia without associated inflammatory infiltrates. Fungal organisms were not seen in osseous or nervous tissues. A granulomatous osteomyelitis with extensive osteolysis and focally extensive malacia in the underlying nervous tissue were diagnosed.
Granulation tissue is apparent within the intratrabecular spaces.
Osteoclasts line bony trabeculae near site of osteolysis. The presence of cutaneous lesions and the isolation of T. mentagrophytes lead to the diagnosis of dermatophytosis. Only one case of dermatophytosis caused by M. gypseum in Budgerigars was found in the literature. The appearance of the cutaneous lesion, its location, and the fact that it did not spread to other cutaneous areas are typical features of dermatophytoses in birds. However, the lack of pruritus and the severity of the cutaneous lesion that extended to the adjacent bone, causing lysis, and reaching the brain are unusual.