MUCOPOLYSACCHARIDOSIS II (MPS II) IN A FREE-LIVING KAKA (NESTOR MERIDIONALIS) IN NEW ZEALAND

A lysosomal storage disease, identified as a mucopolysaccharidosis (MPS), was diagnosed in a free-living Kaka (Nestor meridionalis), an endemic New Zealand parrot, which exhibited weakness, incoordination, and seizures. Histopathology showed typical colloid-like cytoplasmic inclusions in Purkinje cells and many other neurons throughout the brain. Electron microscopy revealed that storage bodies contained a variety of linear, curved, or circular membranous profiles and electron-dense bodies. Because the bird came from a small isolated population of Kaka in the northern South Island, a genetic cause was deemed likely. Tandem mass spectrometry revealed increased levels of heparan sulfatederived disaccharides in the brain and liver compared with tissues from controls. Enzymatic assays documented low levels of iduronate-2-sulfatase activity, which causes a lysosomal storage disorder called MPS type II or Hunter syndrome. A captive breeding program is currently in progress, and the possibility of detecting carriers of this disorder warrants further investigation.

Automated summary

A free-living Kaka parrot was diagnosed with mucopolysaccharidosis, with typical histopathological and electron microscopic findings. Genetic factors are suspected to be the cause, as the bird came from a small isolated population. A captive breeding program is ongoing with further investigation into carriers of the disorder.