Page 1031 - Veterinary Toxicology, Basic and Clinical Principles, 3rd Edition

Mushroom Toxins Chapter | 67 963

VetBooks.ir detection of psilocin and psilocin glucuronide in urine, such as acute pancreatitis. The diagnostic challenge is that
Diagnosis of psilocybin exposure is confirmed by the
many of the more toxic mushrooms cause initial gastroin-
testinal signs. Cyclopeptides cause vomiting and diarrhea
serum, and blood. A number of methodologies are avail-
able and are routinely used in forensic investigations after a lag period similar to that seen with the gastrointes-
(Kamata et al., 2003; Albers et al., 2004; Laussmann and tinal irritants. Therefore, any animal presenting with gas-
Meier-Giebing, 2010). Because of the infrequent presenta- trointestinal signs after a known history of mushroom
tion of hallucinogenic mushroom poisoning in animals, ingestion must be carefully assessed.
these methodologies are not routinely available at veteri- Treatment is entirely nonspecific and supportive.
nary diagnostic laboratories. Vomiting is a hallmark of poisoning by gastrointestinal
irritant mushrooms. Thus, in most cases, the stomach has
already been emptied, and emetics are not necessary.
GASTROINTESTINAL IRRITANTS
Activated charcoal is thought to adsorb most of the toxins
This group includes mushrooms that result in gastroenteri- in this group and should be administered orally unless
tis as the primary clinical sign. There are very few reports there is protracted vomiting. There are no specific anti-
in the veterinary literature. Genera included are Agaricus, dotes for the toxins in this group. Treatment is aimed at
Boletus, Chlorophyllum, Entoloma, Lactarius, Omphalotus, rehydration and correction of serum electrolyte
Rhodophyllus, Scleroderma,and Tricholoma. The specific abnormalities.
toxins in most have not been identified (Spoerke, 1994).
One of the mushrooms in this group commonly RENAL TOXIC MUSHROOMS
reported to cause poisoning is Chlorophyllum molybdites.
This mushroom is commonly found in the United States Orellanine-containing mushrooms cause acute renal fail-
except in the colder, northern areas, and the principal ure without any hepatic insult. Mushrooms of the genus
toxin has not been clearly identified. Clinical signs of Cortinarius contain the highly potent nephrotoxin orella-
nausea, vomiting, and diarrhea appear 1 6 h after inges- nine (Frank et al., 2009), which is similar in chemical
tion in humans, and there is complete recovery within structure to paraquat. Cortinarius rubellus and
24 48 h (Blayney et al., 1980). A dog with C. molybdites Cortinarius orellanosus exist in North America; C. rubel-
poisoning had clinical signs of drooling and diarrhea, lus is found in northern areas of both the east and west
whereas a horse that had presumably eaten several bites coasts while C. orellanosus is reported in Michigan but
of C. molybdites died (Beug, 2009). Omphalotus olearius, its entire geographic distribution is currently unknown. In
Omphalotus subilludens, and Lampteromyces japonicus North America, there are only a few reported cases in
contain illudin S (Bresinsky and Besl, 1990b). humans, but poisonings occur with much greater fre-
Illudin S is a sesquiterpene with a unique chemical quency in western and central Europe. In humans, symp-
structure. In humans, vomiting and diarrhea occur toms gradually develop over 2 20 days after ingestion.
1 2.5 h after ingestion (French and Garrettson, 1988). In In general, gastrointestinal signs occur a few days after
a pot-bellied pig, death was reported 5 h after it ingested exposure, and renal failure develops 4 15 days after
a fruiting body of Scleroderma citrinum (Galey et al., ingestion. Hemodialysis may be necessary until renal
1990). The pig vomited and collapsed 20 min after expo- function gradually improves. There are no reports of orel-
sure and remained weak and recumbent until death. The lanine poisoning in pets; however, poisoning was docu-
toxins in S. citrinum have not been characterized. In mented in grazing sheep in Norway ( Overa ˚s et al., 1979).
Boletus satanas, lectins may contribute to serious gastro- A. smithiana has resulted in delayed renal failure in
enteritis in humans. Lectins, which are storage proteins humans without evidence of hepatic dysfunction (West
that may play a role in plant defense, are widely distrib- et al., 2009). The toxin is allenic norleucine. Key clinical
uted in many species of mushrooms (Wang et al., 1998). features are vomiting and abdominal pain with little or no
Poisonings by mushrooms of this group are rarely diarrhea within a few hours of ingestion. Renal failure
fatal; hence, they are likely to be underreported by owners develops 1 4 days after exposure and may require sev-
and seldom recorded in the literature. After a usually eral weeks of hemodialysis before recovery. There are no
short latent period of 15 min to 2 h after ingestion, an ani- reports of A. smithiana poisoning in animals, but it is a
mal may present with vomiting, diarrhea, and abdominal common mushroom in the Pacific Northwest.
pain. Usually, these clinical signs resolve spontaneously
within a few hours, but they may last 1 or 2 days. The RAMARIA FLAVO-BRUNNESCENS
clinical signs may resemble any other common cause of
gastroenteritis in small or large animals, including bacte- This mushroom is found in North America, Australia,
rial and viral infections, sudden diet changes or eating China, Brazil, and Uruguay and has caused poisoning in
spoiled foods, and inflammatory mediated syndromes cattle and sheep (Kommers and Santos, 1995). Ramaria