Clonality and α-a Recombination in the Australian Cryptococcus gattii VGII Population - An Emerging Outbreak in Australia

BACKGROUND: Cryptococcus gattii is a basidiomycetous yeast that causes life-threatening disease in humans and animals. Within C. gattii, four molecular types are recognized (VGI to VGIV). The Australian VGII population has been in the spotlight since 2005, when it was suggested as the possible origin for the ongoing outbreak at Vancouver Island (British Columbia, Canada), with same-sex mating being suggested as the driving force behind the emergence of this outbreak, and is nowadays hypothesized as a widespread phenomenon in C. gattii. However, an in-depth characterization of the Australian VGII population is still lacking. The present work aimed to define the genetic variability within the Australian VGII population and determine processes shaping its population structure. METHODOLOGY/PRINCIPAL FINDINGS: A total of 54 clinical, veterinary and environmental VGII isolates from different parts of the Australian continent were studied. To place the Australian population in a global context, 17 isolates from North America, Europe, Asia and South America were included. Genetic variability was assessed using the newly adopted international consensus multi-locus sequence typing (MLST) scheme, including seven genetic loci: CAP59, GPD1, LAC1, PLB1, SOD1, URA5 and IGS1. Despite the overall clonality observed, the presence of MATa VGII isolates in Australia was demonstrated for the first time in association with recombination in MATα-MATa populations. Our results also support the hypothesis of a "smouldering" outbreak throughout the Australian continent, involving a limited number of VGII genotypes, which is possibly caused by a founder effect followed by a clonal expansion. CONCLUSIONS/SIGNIFICANCE: The detection of sexual recombination in MATα-MATa population in Australia is in accordance with the natural life cycle of C. gattii involving opposite mating types and presents an alternative to the same-sex mating strategy suggested elsewhere. The potential for an Australian wide outbreak highlights the crucial issue to develop active surveillance procedures.Fabian Carriconde, Félix Gilgado, Ian Arthur, David Ellis, Richard Malik, Nathalie van de Wiele, Vincent Robert, Bart J. Currie, Wieland Meye

Twenty two cases of canine neural angiostronglyosis in eastern Australia (2002-2005) and a review of the literature

Cases of canine neural angiostrongylosis (NA) with cerebrospinal fluid (CSF) evaluations in the peer-reviewed literature were tabulated. All cases were from Australia. A retrospective cohort of 59 dogs was contrasted with a series of 22 new cases where NA was diagnosed by the presence of both eosinophilic pleocytosis and anti-Angiostrongylus cantonensis immunloglobulins (IgG) in CSF, determined by ELISA or Western blot. Both cohorts were drawn from south east Queensland and Sydney. The retrospective cohort comprised mostly pups presented for hind limb weakness with hyperaesthesia, a mixture of upper motor neurone (UMN) and lower motor neurone (LMN) signs in the hind limbs and urinary incontinence. Signs were attributed to larval migration through peripheral nerves, nerve roots, spinal cord and brain associated with an ascending eosinophilic meningo-encephomyelitis. The contemporary cohort consisted of a mixture of pups, young adult and mature dogs, with a wider range of signs including (i) paraparesis/proprioceptive ataxia (ii) lumbar and tail base hyperaesthesia, (iii) multi-focal central nervous system dysfunction, or (iv) focal disease with neck pain, cranial neuropathy and altered mentation. Cases were seen throughout the year, most between April and July (inclusive). There was a preponderance of large breeds. Often littermates, or multiple animals from the same kennel, were affected simultaneously or sequentially. A presumptive diagnosis was based on consistent signs, proximity to rats, ingestion/chewing of slugs or snails and eosinophilic pleocytosis. NA was diagnosed by demonstrating anti-A. cantonensis IgG in CSF. Detecting anti-A. cantonensis IgG in serum was unhelpful because many normal dogs (20/21 lb dogs; 8/22 of a hospital population) had such antibodies, often at substantial titres. Most NA cases in the contemporary series (19/22) and many pups (16/38) in the retrospective cohort were managed successfully using high doses of prednisolone and opioids. Treatment often included antibiotics administered in case protozoan encephalomyelitis or translocated bacterial meningitis was present. Supportive measures included bladder care and physiotherapy. Several dogs were left with permanent neural deficits. Dogs are an important sentinel species for NA. Human cases and numerous cases in tawny frogmouths were reported from the same regions as affected dogs over the study period

Ovarian cancer molecular pathology.

Peer reviewe

Comparing immunochromatography with latex antigen agglutination testing for the diagnosis of cryptococcosis in cats, dogs and koalas

AbstractAlthough the point-of-care cryptococcal antigen lateral flow assay (LFA) has revolutionized the diagnosis of cryptococcosis in human patients, to date there has been no large-scale examination of this test in animals. We therefore assessed the LFA in cats, dogs and koalas suspected of having cryptococcosis. In sum, 528 serum specimens (129 from cats, 108 from dogs, 291 from koalas) were tested using the LFA and one of two commercially available latex cryptococcal antigen agglutination test (LCAT) kits. The LCAT is a proven and well-accepted method in veterinary patients and therefore taken as the “gold standard” against which the LFA was compared. The LFA achieved a sensitivity of 92%, 100%, and 98% in cats, dogs, and koalas, respectively, with corresponding negative predictive values of 94%, 100%, and 98%. The specificity of the LFA was 81%, 84%, and 62% for cats, dogs, and koalas, respectively, with corresponding positive predictive values of 76%, 48%, and 69%. These findings suggest the most appropriate role for the LFA is as a screening test to rule out a diagnosis of cryptococcosis in cats, dogs, and koalas. Point-of-care accessibility makes it equally suited for use in the field and as a cage-side test in veterinary hospitals. The suboptimal specificity of the LFA makes it less suited to definitive confirmation of cryptococcosis in animals; therefore, all LFA-positive test results should be confirmed by LCAT testing. The discrepancy between these observations and the high specificity of the LFA in humans may reflect differences in the host-pathogen interactions amongst the species.</jats:p

Cryptococcosis with ocular and central nervous system involvement in a 3‐year‐old dog

To date, cryptococcosis remains sporadic in Europe, and this is a case of canine cryptococcosis with ocular and CNS involvement in continental Europe with identification of the organism on cerebral spinal fluid (CSF) cytology and description of the clinical and MRI features, and outcome