Sequential opportunistic infections in two German Shepherd dogs

Abstract

Two German Shepherd dogs with sequential opportunistic infections are described. The first was a 2-year-old male with cryptococcal rhinitis that spread to involve the optic nerves and brain. It was successfully treated with combination therapy utilising amphotericin B administered for 2 years, but the dog developed a disseminated Aspergillus deflectus infection 5 years later and was euthanased. The second case was a 4-year-old male that presented for a severe, deep-seated infection of the right antebrachium, with gradual extension to contiguous tissues. Neosartorya fischeri (anamorph; Aspergillus fischerianus) was isolated in pure culture and detected in histological sections. The infection was refractory to itraconazole, but resolved after amputation of the affected limb. Five months later, the dog developed a localised cutaneous lesion on the proximal pelvic limb, from which Pythium insidiosum was isolated and then visualised in tissue sections, together with a structure thought to be grass seed. This lesion was treated by wide surgical resection, although it was reported that the dog died of disseminated disease some months later. These cases provide further circumstantial evidence that young adult German Shepherd dogs have a predilection to developing invasive infections with fungi and other saprophytic pathogens.

New taxa in Aspergillus section Usti

“…This species is also common in indoor air (Houbraken et al 2007, Slack et al 2009) and is able to colonise water distribution systems (Hageskal et al 2011). Other species related to A. ustus can also cause human or animal infections; A. granulosus was found to cause disseminated infection in a cardiac transplant patient (Fakih et al 1995), while A. deflectus has been reported to cause disseminated mycosis in dogs (Jang et al 1986, Kahler et al 1990, Robinson et al 2000, Schultz et al 2008, Krockenberger et al 2011). …”

New Insights into the In Vitro Susceptibility of Pythium insidiosum

“…The third method, macrodilution (12,(19)(20)(21) or microdilution (7,8,22,23) in broth, utilizes the CLSI M38-A2 protocols (11) and inocula with final concentrations of 2 to 3 ϫ 10 3 zoospores/ml. Additionally, some studies have reported that P. insidiosum isolates were insensitive or resistant to all of the antimicrobials evaluated (24)(25)(26)(27) or described the MICs obtained by in vitro susceptibility tests (3,4,28) without describing how the inocula were prepared or how the susceptibility test was performed. This diversity in susceptibility testing techniques likely correlates with the diversity of MICs observed for P. insidiosum (see Table S2 in the supplemental material).…”

Successful treatment of bilateral paecilomyces pyelonephritis in a German shepherd dog

“…The exact mechanism of their susceptibility to fungal infections is unclear; however, defects in mucosal immunity through IgA dysregulation (Day and Penhale ) and depressed local cellular responses (Pérez and others ) are possible. As a result of this susceptibility, recurrent and sequential fungal infections are reported in German shepherd dogs (Krockenberger and others ).…”