Acute systemic toxoplasmosis was diagnosed in an adult male domestic shorthair cat, that had been on cyclosporine A (CsA) immunomodulatory therapy for feline atopy, over an 8 month period. CsA has shown promising results as an immunosuppressive agent in the cat the treatment of eosinophilic plaque and granulomas, allergic cervico-facial pruritus, feline atopy and other immune-mediated dermatoses. However, as it is being used more frequently, activation of quiescent infections may also be seen as an adverse effect of this treatment, which inhibits T-lymphocyte function. The present case report describes a newly acquired, acute Toxoplasma gondii infection following treatment with CsA, as characterized by severe hepatic and pancreatic pathology and a heavy T. gondii parasitic load.
Reference: Last et al, Vet Dermatol 15:194-198, 2004.

Abdominal ultrasound is often recommended as an additional screening test to aid in the diagnosis of spontaneous hyperadrenocorticism. Sometimes the procedure is done the same day as cortisol screening testing (i.e., LDDST or ACTH response test). However, the question is whether the stress of minor procedures, such as abdominal ultrasound, skin scraping or biopsy, dentistry, intradermal allergy testing, minor surgery, or even anesthesia will alter results of these tests. A recent study performed LDDST 5 times at weekly intervals in 6 healthy normal dogs. During the testing period, a 20-min mock abdominal ultrasound was performed weekly in all dogs at the 2, 4, 6, and 8 hr time points. In another study, cortisol concentrations were measured before and immediately after the mock ultrasound exam. While stress of the mock ultrasound procedure did not alter the LDDST results in most dogs, all dogs had significantly increased cortisol concentrations after the ultrasound procedure. Results of this study suggest that ultrasonographic procedures should be performed a minimum of two hrs before performing coritsol screening tests to avoid falsely elevated cortisol levels that could lead to misinterpretation (i.e., false positive results). Alternatively, the ultrasound procedure could be scheduled following dynamic testing of adrenal function.
Reference: May et al., Am J Vet Res 65:267-270, 2004.