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Flashcards in Inorganic Arsenic Deck (29)
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1
Q

What is the main difference between organic and inorganic arsenic toxicosis?

A

Inorganic arsenic = corrosive GI disease

Organic arsenic = peripheral neurotoxin (less toxic)

2
Q

What is inorganic arsenic used for?

A

insecticides, herbicides, fungicides, and rodenticides

also found in paint, pigments, detergents, and building materials

3
Q

T/F: Milk from poisoned cows can be toxic to calves

A

TRUE

4
Q

What are the 3 oxidative states of inorganic arsenic?

A

Elemental
Tivalent = arseNITE
Pentavalent = aresenAte

these will react with -SH groups (effects MOA and course treatment)

5
Q

What is the oral LD for most species and how is inorganic categorized base on the toxicity?

A

HIGHLY TOXIC

1-25 mg/kg

6
Q

T/F: Inorganic arsenic toxicosis can be acute, peracute, and chronic

A

FALSE

**THERE IS NO CHRONIC TOXICITY

acute, peracute, subacute

7
Q

Which form of inorganic arsenic is poorly absorbed?

A

Elemental

8
Q

What animals are most susceptible to inorganic arsenic poisoning?

A

Herbivores

dogs can be poisoned via ant and roach baits

swine and chickens are rarely poisoned

9
Q

Which form is more toxic, arsenite or arsenate?

A

Arsenite (trivalent) is more toxic than Aresenate (pentavalent)

more toxic than organic arsenic

*pentavalent is converted to trivalent in vivo

10
Q

How is inogranic arsenic absorbed?

A

absorbed from the GIT, intact skin, and inhalation

11
Q

What is the distribution of inogranic arsenic?

A

all over the body but achieves highest concentrations in the KIDNEY, LIVER, and hair, hoof, nail, and skin

(kidney and liver due to high blood flow)

12
Q

T/F: inogranic arsenic crosses the BBB

A

False

poorly crosses the BBB

13
Q

What change occurs to pentavalent inogranic arsenic in the liver?

A

Changes to MORE TOXIC trivalent arsenic aka arsenite

14
Q

What is the metabolism and excretion of inogranic arsenic?

A

Partly metabolized in the liver and kidney by methylation

rapidly excreted in the urine (within 48 hours)
*small amts excreted in feces, milk, saliva, sweat, hair, and exhalation

15
Q

what is the MOA of inorganic arsenic?

A

Trivalent (arsenite): binds to 2 -SH groups of lipoic –> SLOWS GLYCOLYSIS and TCA cycle = inhibiting energy production

Pentavalent (arsenate): uncouples oxidative phosphorylation (similar to PCP) and may interfere with B1 and B12 metabolism

both = lack of energy = tissue damage

*locally corrosive

16
Q

What tissues are the most severely affected from inorganic arsenic poisoning?

A
Tissues that are rich in oxidative enzymes:
intestines
liver
kidney
GI mucosa
capillaries -endothelium (hemorrhage)
17
Q

What clinical signs are associated with PERACUTE inorganic arsenic poisoning?

A

most severe

sudden death or severe colic, collapse and death hypovolemic shock

18
Q

What clinical signs are associated with ACUTE inorganic arsenic poisoning?

A

rapid onset - severe colic, staggering, salivation, vomiting, thirst, watery dhr - hemorrhagic, possible hematuria

death in 1 - 3 days

19
Q

What clinical signs are associated with SUBACUTE inorganic arsenic poisoning?

A

Colic, anorexia, depression, dhr with blood or mucosal shreds, dehydration, partial paralysis of the hind limbs, and death in several days

20
Q

What lesions are associated with inorganic arsenic poisoning?

A

Hemorrhagic lesions all over the body

GI mucosal edema/hem. with sloughing or perforation, liver and kidney damage, capillary degeneration, skin lesions and blistering (from skin exposure)

21
Q

What is the BEST antemortem specimen for inorganic arsenic testing?

A

URINE

22
Q

What are the best postmortem specimen for inorganic arsenic testing?

A

Liver and kidney

Other: GI contents, vomitus, feces, milk, suspected source

23
Q

What is the normal level of inorganic arsenic residues in tissue?

A

0.5 ppm

***More than 7-10ppm in the liver or kidney = strong indication of inorganic toxicosis

24
Q

What lab values will be elevated in a patient with inorganic arsenic poisoning?

A

Increased PCV and BUN

25
Q

What criteria do you rely on to diagnose inorganic arsenic poisoning?

A

hx, signs of sudden bloody dhr/watery dhr with mucosal shreds, lesions, and lab values

***there are MANY ddx for this toxicant

26
Q

What does emergency and supportive treatment for inorganic arsenic poisoning include?

A

IVF, blood transfusion, tx of acidosis, ABs, Vitamins/antioxidants, analgesics etc

27
Q

What is the decontamination protocol for inorganic arsenic toxicosis?

A

Gastric lavage - should only be done if there is NO evidence of damage (so early on in dz)
Mineral oil to coat GIT
Activated charcoal is not very effective

Emetics and strong cathartics are contraindicated**

28
Q

What specific treatment/therapy is available for inorganic arsenic poisoning?

A

must have a definitive dx
Chelation therapy: Dimercaprol - not 100% effective
Can have dangerous side effects - should only be used as a last resort

Dimercaptosuccinic acid (DMSA) is a less effective but safer chelator

29
Q

What is the prognosis inorganic arsenic poisoning?

A

Grave

unless treated VERY early