Toxicology 2019 Flashcards
Dr. Sierra Salopek is currently an anatomic pathology resident at Oklahoma State University. She received fixed tissues collected from an adult goat during a field necropsy, form a case where 5 goats and 5 sheep were found dead on a piece of property -half were found on land and half were found in the water, which is a backyard type pond. The clinician is concerned about blue green algae being the culprit. Sierra mentioned she did not see any significant histologic lesions and thus was going to rule out Cyanobacteria as a possible differential. You, however, say ‘au contraire’ - there are those neurotoxin Cyanobacteria that do not leave any histologic lesions behind. Name the two neurotoxins and their mechanism of action.
Anatoxin A - mimics acetylcholine Anatoxin A(S) - inhibits acetylcholinesterase
Acute selenium poisoning in swine has been associated with: (choose ONE BEST answer)
- eosinophilic meningoencephalitis
- leukoencephalomalacia
- polioencephalomalacia
- poliomyelomalacia
- nigropallidalencephalomalacia
Poliomyelomalacia
Miso, a 4.3 kg two-year-old FS Terrier dog presented to the VTH ECC early Tuesday morning for ingesting 165 g of semi-sweet chocolate chips 1-2 hours prior to presentation. Before arriving at the clinic, Milo’s was reported to have vomited 4-5 times, and the vomit consisted mostly of chocolate. Miso has no prior medical history and has been a healthy dog. Now she is exhibiting whole body tremors, with dry tacky mucous membranes.
Assess the vitals:
T: 101.8 F
P: 230 beats/minute
R: 50 breaths/minute
T: 101.8 F (NORMAL)
P: 230 beats/minute (HIGH)
R: 50 breaths/minute (HIGH)
Miso, a 4.3 kg two-year-old FS Terrier dog presented to the VTH ECC early Tuesday morning for ingesting 165 g of semi-sweet chocolate chips 1-2 hours prior to presentation. Before arriving at the clinic, Milo’s was reported to have vomited 4-5 times, and the vomit consisted mostly of chocolate. Miso has no prior medical history and has been a healthy dog. Now she is exhibiting whole body tremors, with dry tacky mucous membranes.
Name the TWO methylxanthine compounds present in chocolate.
The one with the long half-life: _________________________
The one with the short half-life: ________________________
Theobromine
Caffeine
Miso, a 4.3 kg two-year-old FS Terrier dog presented to the VTH ECC early Tuesday morning for ingesting 165 g of semi-sweet chocolate chips 1-2 hours prior to presentation. Before arriving at the clinic, Milo’s was reported to have vomited 4-5 times, and the vomit consisted mostly of chocolate. Miso has no prior medical history and has been a healthy dog. Now she is exhibiting whole body tremors, with dry tacky mucous membranes.
ALL of the following would be the BEST recommended treatment options for Miso EXCEPT (choose ONE BEST answer):
- Maropitant SQ followed by multiple doses of activated charcoal PO
- Control tremors with diazepam, IV
- Monitor ECG and blood pressure
- IV fluid therapy, LRS
- IV lipid rescue therapy
IV lipid rescue therapy
In addition to ivermectin, choose TWO other toxins that have been associated with blindness in dogs.
- Lead
- Penitrem A
- Pyrethrins
- Chlorinated hydrocarbons (organochlorines)
- Glow jewelry
Lead, Pyrethrins
Name the SPECIFIC mutation AND describe how this mutation plays a role in making some dogs way more sensitive to ivermectin (and other drugs).
MDR1 - multi drug resistant gene
This mutation results in lack of production of p-glycoprotein, which is a transporter of the drug.
This results in retention of the chemicals in the brain due to lack of p-glycoprotein at the BBB and lack of excretion via kidneys or liver.
Nismo is a one-year-old 23.3 kg MN Golden Retriever dog presenting for acute onset of blindness and mydriasis. Earlier in teh day, Nismo was completely normal when he went outside to play. When he was brought in later in the day because it started to rain, he was noted to be ‘running into furniture and moving like he could not see.’ There are other dogs in the home that are doing fine. The horses at home were dewormed with ivermectin the previous day. No other toxins are available - so they say! While waiting in the lobby, Nismo collapsed and laid there for a while with his left back leg twitching.
Treatment for Nismo consisted of IV lipid therapy, IV fluid therapy at 2X maintenance, along with any basic supportive care that was deemed appropriate. Name one treatment option that should have been considered in this treatment plan AND describe your prognosis conversation with the client (particularly regarding the signs the dog is displaying).
Cholestyramine; prognosis varies may be one day or 30 days of supportive care
There is a lot of chatter on my vettox list serve right now regarding the current use of a particular compound being used in certain regions of Australia to control a major feral cat problem. The pesticide is mixed into sausage-like links that are aerially dropped in these areas, with the intent of trying to kill two million feral cats by 202. This particular pesticide has been largely banned in the US (historically used to kill coyotes and rodents) due to high risks of abusing secondary poisonings in non-target animals. The pesticide works by lethal synthesis - incorporating itself into the Kreb’s cycle ultimately shutting down ATP production, and primarily affects the GIT, CNS, and heart in most animal species. Name the pesticide: _____________________
1080
The mycotoxin ___________________ (found in clovers and alfalfa/legumes) is responsible for causing ‘slobbering disease’ in horses. There is also an unknown mycotoxin that can be found in alsike clover (Trifolium pretense and Trifolium hybridum) that can cause __________________ disease only in horses.
Slaframine
Liver
Select ALL of the following statements that are TRUE regarding strychnine:
- Strychnine is a legally used below-ground use rodenticide, and formulations often contain red and green dyed grain.
- Strychnine is rapidly absorbed from the GIT, and it inhibits the GABA- and glutamate-gated chloride channels, leading to muscle paralysis and terminal tonic-clonic seizure activity.
- Once the patient is sedated, consideration should be given to placement of an endotracheal tube with oxygen support, because the cause of death is thought to be due to asphyxia from the prolonged paralysis of the respiratory muscles during seizure activity.
- Once sedated and a cuffed endotracheal tube is in place, one should consider performing a gastric lavage followed by the use of activated charcoal and a cathartic - but this procedure must be done carefully to avoid ‘stimulus-induced seizure activity.’
- Important additional supportive care measures for affected patients would include monitoring the acid base status, IV fluid therapy to maintain hydration, a quiet environment, and controlling body temperature
- Strychnine is a legally used below-ground use rodenticide, and formulations often contain red and green dyed grain. (TRUE)
- Strychnine is rapidly absorbed from the GIT, and it inhibits the GABA- and glutamate-gated chloride channels, leading to muscle paralysis and terminal tonic-clonic seizure activity. (FALSE)
- Once the patient is sedated, consideration should be given to placement of an endotracheal tube with oxygen support, because the cause of death is thought to be due to asphyxia from the prolonged paralysis of the respiratory muscles during seizure activity. (TRUE)
- Once sedated and a cuffed endotracheal tube is in place, one should consider performing a gastric lavage followed by the use of activated charcoal and a cathartic - but this procedure must be done carefully to avoid ‘stimulus-induced seizure activity.’ (TRUE)
- Important additional supportive care measures for affected patients would include monitoring the acid base status, IV fluid therapy to maintain hydration, a quiet environment, and controlling body temperature. (TRUE)
You diagnose nitrate poisoning in a group of yearling cattle that were recently introduced to a new batch of Sudan grass hay. Which of the following is the MOST EFFECTIVE treatment? (Choose ONE BEST answer)
- Sodium thiosulfate
- Calcium gluconate
- Thiamine (vitamin B1)
- Methylene blue
- Atropine
Methylene blue
Roomy is a seven-year-old MC 3.3 kg Yorkshire Terrier dog that presented to the VTH ECC for permethrin toxicity. The owners had mixed some Sergeant Flea and Tick Squeeze topical liquid permethrin product (45% permethrin) in some cat food on a plate and placed the paper plate in a tree to kill yellow jackets. The wind blew the paper plate out of the tree, and the owners witnessed Roody eating the cat food. Four hours later, Roody was ‘agitated, drooling excessively and trembling with whole body tremors.’ Roody has no pre-existing health issues, is up-to-date on his vaccines, and is not currently on any medications.
The decision was made to NOT initiate any decontamination procedures at this time - would you concur AND why/why not?
Name the BEST drug you should use FIRST to control the tremors: ___________________.
T/F: IV lipid therapy should be considered a viable treatment option in this patient based on the literature of permethrin toxicities.
T/F: Atropine, IV, will effectively control the excessive drooling in this patient.
No - can control tremors, then sedate and do gastric lavage
Methocarbamol
TRUE
FALSE
ALL of the following are TRUE regarding paraquat EXCEPT (choose ONE BEST answer):
- Paraquat is a popular herbicide used on many crops in the US.
- Following an acute oral exposure, vomiting and abdominal pain are commonly reported due to the irritant nature of paraquat itself along with the emetic that is present in paraquat liquid formulations.
- Paraquat causes severe respiratory inflammation, necrosis, edema, and hemorrhage; therefore intensive oxygen therapy is vital to the successful treatment of these patients
- Five to seven days post exposure, renal necrosis is observed, mostly due to the fact that the vast majority of paraquat is excreted unchanged through the kidneys.
FALSE - Paraquat causes severe respiratory inflammation, necrosis, edema, and hemorrhage; therefore intensive oxygen therapy is vital to the successful treatment of these patients
When PolyTetraFluoroEthylene lined products are heated to a temperature above 500 F, they release fumes and particulates into the air that cause severe respiratory distress to all animal species. Name the species that is UNIQUELY sensitive to this toxic effect: _________________.
Birds
Name two common and reasonable sources of PTFE in and around the house and home that can be a risk to the above listed species when overheated.
Baking sheets
Clothes iron
Name the weak estrogenic mycotoxin found in grains that can be problematic to cattle and swine. There was a recent article on the Promed list serve describing hormonal imbalances in pre-pubertal girls ingesting this mycotoxin contaminated corn, wheat, rice, and oats in India.
Zearalenone
Dr. Dave Clark, an equine practitioner in southeastern ID, called and described seeing two horses on the same property exhibiting an acute onset of peripheral limb edema and laminitis. His primary differential was equine viral arteritis causing some type of vasculitis. Name the plant that grows all throughout the PNW that is in the mustard family that can cause similarly clinical signs. GENUS or BEST COMMON NAME
__________________________
Hoary alyssum
ALL of the following can be associated with tall fescue EXCEPT (choose ONE BEST answer)
- A lot of tall fescue grown in the US is infected with the endophyte Neotyphodium coenophialum.
- Ergotamine is the primary mycotoxin found in fescue seeds and is responsible for peripheral vasodilation, leading to severe pain and inflammation in affected tissues.
- Summer slump is commonly reported in the summer months in cattle ingesting high levels of the toxin.
- Fescue foot is commonly reported in the winter months in cattle ingesting high levels of the toxin.
- Prolonged gestation, thickened placentas, dystopias, dysmature foals, and abortions can be seen in horses ingesting high levels o the toxin any time of year.
FALSE Ergotamine is the primary mycotoxin found in fescue seeds and is responsible for peripheral vasodilation, leading to severe pain and inflammation in affected tissues.
