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Flashcards in Diagnostic toxicology Deck (20)
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1

What is the most important aspect in dealing with toxicosis? What are specific treatment and prognosis based on?

Accurate/confirmed diagnosis

2

T/F: Diagnosing poisoning is the same as diagnosing other species--by process of elimination

TRUE

3

How is a tentative diagnosis obtained?

Can be obtained by detailed history, thorough clinical and postmortem examinations

4

How is a presumptive diagnosis reached? What can sometimes help?

  • Can be reached when the history and clinical signs are supported by circumstantial evidence and identification of the source of poisoning
  • Sometimes response to a specific antidotal treatment may help making a presumptive diagnosis

5

How is a confirmed diagnosis reached?

May be reached by using all criteria of diagnosis including laboratory work (sampling, interpretation)

6

What are the 5 criteria of diagnosis? Which is unique to toxicosis?

  1. Case history
  2. Clinical signs
  3. Postmortem findings
  4. Laboratory diagnosis
  5. Laboratory animal tests
    1. Unique to toxicosis

7

Case history--5 aspects?

  • Looking for the evidence
  • Relying on information provided by the owner or caretaker may be misleading
  • Make sure that the animal has ingested or has been exposed to the poison at a certain level 
  • The food and water should be examined for the presence of toxic agents
  • Information and questions depend on if the animal is a farm or companion animal

8

What specific questions should you ask when discussing case history of farm animal toxicosis?

  • # of animals
  • # of effected
  • # dead
  • Course of disease
  • Type of management
  • Feeding
  • Vaccination
  • Use of herbicides/insecticides
  • Past illness
  • Presence of poisonous plants
  • Detailed clinical signs, postmortem findings, etc.

9

What questions are included in the small animal case history?

  • Is the animal indoors or outdoors
  • Use of any drugs, insecticides, pesticides
  • Household chemicals
  • Vaccination, etc.

10

Clinical signs--what's included/not included

  • Details of clinical signs
  • Complete and thorough clinical examination
  • Most diseases do not have pathognomonic signs

11

Postmortem findings

  • Include both gross and microscopic examinations
  • Must be done in legal cases
  • Negative results are as good as positive results

12

Laboratory diagnosis (6)

  • Clinical pathology
  • Chemical analysis
    • Positive chemical results consistent with other criteria may confirm diagnosis
    • Should be done by a qualified toxicology lab
  • Accuracy of chemical results depends on good sampling
  • Interpretation of results should be done carefully considering other evidence
  • Positive results do not always mean intoxication
  • Negative results do not always mean that poisoning did not occur

13

Laboratory animal tests (6)

  • Usually done by the toxicoloy lab
  • Administration of the suspected materia (food or water) to a susceptible animal and observing the effects
  • Important in bacterial, fungal, plant toxins and feed additives in animal feeds
  • It is more relevant to administer the suscpected material to the same species that was exposed to the suspected toxin
  • Positive results may be helpful in aiding diagnosis
  • Negative results do not eliminate the possibility of intoxication  

14

Submitting specimens for chemical analysis:

Specimens should be accompanied by?

Evaluation?

Ideal specimen?

  • Should be accompanied with a complete history, clinical signs, postmortem findings and other information including the vet's name, address and phone #; owner's name, address, phone # and animal's species, breed, sex, age, and weight
  • Specimens will be evaluated for toxicants quantitatively and qualitatively
  • Specimens should be representing, avoiding dilution, contamination, or putrefaction

15

What 8 procedures/precautions must be followed when submitting specimens for chemical analysis?

  1. Specimens should be taken free of chemical contamination or debris
  2. Specimens should not be washed
  3. Animal and tissue specimens should be frozen
  4. Blood samples should be refrigerated while other body fluids should be frozen
  5. Packaging specimens from different organs separately
  6. Clean glass or plastic containers that can be tightly sealed should be used
  7. Waterproof ink should be used when labeling specimens and should include owner's name, animal's name, or # and tissue of specimens
  8. Preservatives must not be added to specimens unless indicated as in case of histopathological examination (this has to be mentioned on the label)  

16

Examples of adequate material amounts (7)

  • Serum: 5mL live animal, 10mL dead animal
  • Whole blood: 10mL live or dead animal
  • Urine: 50mL live or dead
  • Vomitus or baits 200g
  • Liver, kidney, or fat 100g
  • Brain: 1/2 frozen and 1/2 in formalin
  • Rumen or stomach contents 500g

17

6 steps in obtaining a serum sample?

  1. Use clean, dry syringes, needles, vials or tubes
  2. Avoid hemolysis by avoiding pressure, aspiration, or shaking of the sample
  3. Allow enough time (1-2hr) for the blood to clot
  4. Put tubes with blood in an oblique position to obtain more serum by increasing the SA
  5. Obtain serum by pouring in another tube, or by centrifugation at 3000 rpm for 15 min and pipetting the serum 
  6. Vials and tubes have to be tightly sealed and labeled, then frozen and transported on ice

18

Sampling feeds or forage for analysis

  • Forages should be cut to length of ~3in
  • Sample size should be on quart or kilogram
  • Green forage or silage should be frozen, or green forage dried
  • Samples should be taken from dif. bales and dif. parts of the bale
  • Samples should be packaged tightly and sealed airtight in plastic bags
  • All letters/instructions should be sealed in a first class mail envelope attached to the mailing container

19

Transporting specimens to a laboratory

  • Liquids (blood, other) should be shipped in glass or heavy plastic containers that can be tightly sealed
  • Tissue specimens can be transported in ziploc plastic bags, glass, or plastic containers
  • Samples should be wrapped individually for mailing
  • Plastic bags, cardboards and coolers are used for transporting 

20

Sealing of packages for legal or insurance purposes (according to FBI, 1996)

  • Pack bulk evidence securely in a box
  • Seal box and mark as 'evidence'
  • Place copy of transmittal letter in envelope and mark 'invoice'
  • Stick envelope to outside of sealed box
  • Wrap sealed box in outside wrapper and seal in gummed paper and address directly to laboratory (Note attention to specific person if possible)