Five cases of tremorgenic mycotoxicosis in dogs - clinical aspects and analytical methods

Tremorgenic mycotoxicosis is a well-recognized cause of acute neurotoxicosis in dogs, most commonly associated with penitrem A (PTA), which is mainly produced by Penicillium crustosum. However, analytical confirmation of such cases is rare. This study describes five clinical cases of canine tremorgenic mycotoxicosis in Germany, together with comprehensive analytical confirmation. All dogs had been presented at the veterinary clinic of Justus-Liebig-University because of acute-onset generalized tremors. Clinical findings, therapeutic measures and final outcome were documented. Samples of gastric content (induced emesis or gastric lavage) and blood serum (if available) were analyzed for several neurotoxic mycotoxins, penitrems A-F, paxilline (PAX), α-cyclopiazonic acid (CPA), and ergoline alkaloids. Analysis was done by enzyme immunoassay (EIA), and by HPLC-MS/MS. EIA of gastric content was positive for PTA in all samples, and for PAX, CPA, and ergoline alkaloids in some. HPLC-MS/MS analysis confirmed the presence of penitrems A-F, PAX, and CPA. Trace levels of PTA, PAX and CPA were also detected in serum samples. Penitrem producing P. crustosum was isolated from gastric content of all animals. This is the first full analytical study on acute canine tremorgenic mycotoxicoses in Germany, and presents comprehensive results along the causal chain of tremorgenic mycotoxicosis. In addition to the penitrems, several other neurotoxic mycotoxins (PAX, CPA, ergoline alkaloids) may play a role in canine mycotoxicosis. While immediate stabilisation and symptomatic treatment are paramount, prompt mycotoxin testing can help identify the source of poisoning during differential diagnosis.