Disseminated Coccidoidomycosis in a Koala ( Phascolarctos cinereus )

Review of some pharmacokinetic and pharmacodynamic properties of anti-infective medicines administered to the koala (Phascolarctos cinereus)

Although koalas are iconic Australian animals, no pharmacokinetic studies of any first-line medicines used to treat diseased or injured koalas had been published prior to 2010. Traditionally, medicine dosages suggested for this species underwent linear extrapolation from those recommended for domesticated species. The koala, a specialist folivore whose natural diet consists of almost exclusively Eucalyptus spp. foliage has anatomical and physiological adaptations for detoxifying their diet which also affect medicine pharmacokinetic profiles. This review addresses aspects of medicine absorption, clearance, and other indices (such as medicine binding to plasma proteins) of enrofloxacin/marbofloxacin and chloramphenicol used for the systemic treatment of chlamydiosis, and fluconazole ± amphotericin, and posaconazole for the treatment of cryptococcosis. Based on observations from published studies, this review includes suggestions to improve therapeutic outcomes when administering medicines to diseased koalas.

The habitat of Coccidioides spp. and the role of animals as reservoirs and disseminators in nature

BACKGROUND

Coccidioidomycosis, a potentially fatal fungal infection, is considered an emergent mycotic disease because of the increased incidence of fungal infections registered over recent years. Infection occurs through the inhalation of arthroconidia from two main species of Coccidioides: Coccidioides immitis and C. posadasii, which are both endemic to arid and semi-arid regions of North America. Coccidioides species not only infect humans but can also infect other mammals (land, aquatic, wild or domestic), reptiles and birds.

OBJECTIVE

To obtain information regarding the habitat of Coccidioides spp. and the animals infected by this fungus and to identify the role that infected animals play as reservoirs and disseminators of this fungus in nature.

MATERIALS

A literature review was conducted to identify the habitat of Coccidioides spp. and the infected non-human animal species targeted by this fungus.

RESULTS AND CONCLUSIONS

This review allows us to suggest that Coccidioides spp. may be classified as halotolerant organisms; nevertheless, to perpetuate their life cycle, these organisms depend on different animal species (reservoirs) that serve as a link with the environment, by acting as disseminators of the fungi in nature.

Meningoencephalitis with secondary obstructive hydrocephalus caused by probable coccidioides species in a buff-cheeked gibbon (Nomascus gabriellae)

An 8-yr-old male buff-cheeked gibbon (Nomascus gabriellae) acutely developed abnormal behavior, decreased appetite, and dull mentation. Mild generalized muscle wasting and weight loss were the only other abnormalities noted on examination. Routine immunodiffusion serology for Coccidioides spp. were IgG and IgM positive. Magnetic resonance imaging of the brain was suggestive of an infectious meningoencephalitis with secondary obstructive hydrocephalus. A ventriculoperitoneal shunt was placed in standard fashion to reduce the imminent risk of mortality from increased intracranial pressure. Postoperative treatment included oral fluconazole, a tapered course of prednisolone, and physical therapy. Clinical signs improved steadily and the gibbon was fit to return to exhibit 8 wk post-shunt placement. This case of coccidioidomycosis demonstrates the complications that can occur with dissemination to the central nervous system and its management. It is the first published report describing the use of ventriculoperitoneal shunt placement in this species.