Amanita muscaria toxicosis in two dogs

Abstract

Objective: To report the manifestations, history, and pathophysiologic basis of disease in 2 dogs with Amanita muscaria toxicosis. Case summaries: Two dogs were evaluated for an acute onset of gastroenteritis and seizures. A. muscaria toxicosis was suspected in each dog after confirmation of environmental exposure and visualization of ingested mushrooms in vomitus. The diagnosis was confirmed following identification of toxic Amanita metabolites in the urine and serum of each dog. Administration of supportive and symptomatic therapies resulted in the complete recovery of each animal. Unique information provided: Ingestion of the mushroom, A. muscaria, by dogs can result in acute gastrointestinal distress that precedes a potentially life-threatening central neurologic syndrome characterized by seizures, tremors, and somnolence. Central nervous system dysfunction results primarily from the actions of ibotenic acid and its decarboxylation product, muscimol, which are analogues of the neurotransmitters glutamate and g-aminobutyric acid (GABA), respectively. Identification of these toxins in the urine and serum of affected dogs using high-performance liquid chromatography (HPLC) provides a definitive diagnosis.

Retrospective multicenter evaluation of the “fly-catching syndrome” in 24 dogs: EEG, BAER, MRI, CSF findings and response to antiepileptic and antidepressant treatment

“…The etiology of this behavior is controversial and has been reported as epileptoid disorders of the visual cortex or simple and complex partial seizures as well as compulsive disorders, hallucinatory behavior, and stereotypy. On the one hand, there are cases reporting FC behavior combined with evident epileptic seizures (e.g., generalized tonic-clinic seizure [GTCS]) [10][11][12]. On the other hand, the literature describes dogs exhibiting FCS, without evident epileptic seizures, with additional behavioral disturbances including licking of the paw and floor, running into objects, lying in the yard and crying, eating mud, following the owner, biting family members without any apparent reason, defecating on the bed [2], or biting and sucking their hindlimbs and pelage [7].…”

“…Currently, an epileptic or behavioral nature of FCS is considered to be most likely. Epileptoid disturbances leading to FCS have been reported to include epileptic discharges of the visual cortex, and they may result either from central nervous system (CNS) disease or from idiopathic epilepsy (IE) [3,[8][9][10][11][12][13]. The FCS has also been cited to be a compulsive disorder, hallucinatory behavior, obsessive-compulsive disorder (OCD), stereotypy [1,9,14,15], or dyskinesia as an extrapyramidal disorder [13].…”

“…The FCS has also been cited to be a compulsive disorder, hallucinatory behavior, obsessive-compulsive disorder (OCD), stereotypy [1,9,14,15], or dyskinesia as an extrapyramidal disorder [13]. The Cavalier King Charles Spaniel (CKCS), Miniature Schnauzer (MS), and Greater Swiss Mountain Dog (GSMD) have been described as being predisposed to this condition [15], although many other dog breeds including the Doberman Pinscher, Airedale Terrier, Miniature Poodle, German Shorthaired Pointer, German Shepherd, Border Collie, Irish Setter, and the English Setter have also been found to display FCS [6,11,[15][16][17][18]. The frequency of the episodes ranged from 30 per hour to once a week, and the age at onset ranged from 1 to 11 years [6,11,13,15,17,18].…”

Respiratory arrest following ingestion of wild mushrooms in 3 dogs (2006–2011)

“…While some mushrooms are nontoxic, others have side effects that range from gastric irritation (eg, vomiting and diarrhea), severe liver failure (eg, marked increases in liver enzyme activities, hypoglycemia, coagulopathies), kidney failure, hemolysis, ataxia, tremors, and seizures. [1][2][3][4][5][6] As dogs are opportunistic scavengers, it is not uncommon for them to ingest mushrooms. This case series reviews 3 dogs with known mushroom ingestion and clinical signs of toxicosis that also developed respiratory arrest.…”

Taxonomic studies of Amanita muscaria (L.) Lam (Amanitaceae, Agaricomycetes) and its infraspecific taxa in Brazil

“…Th is species is referenced in relation to several ancient Old and New World cultures (Brough 1971, Dunn 1974Lowy 1974;Whelan 1974;Saar 1991;Samorini 1992;Hajicek-Dobberstein 1995) and has been reported to cause psychosis in humans (Lampe 1979;Satora et al 2005;Brvar et al 2006), owing to the psychoactive compounds it contains, including muscimol (Wieland, 1968;Krogsgaard-Larsen et al 1981;Stijve & Meijer 1993;Michelot & Melendez-Howell 2003;Tsujikawa et al 2007). Th ere have also been reports of A. muscaria-related accidents involving pets (Rossmeisl et al 2006).…”