Arsenic toxicity: Difference between revisions

 
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==Background==
==Background==
*infamous historical poison
*[[Heavy metal]]
*heavy metal
*Readily absorbed via GI tract and inhalation, poorly via skin  
*sources of exposure: poisoning, contaminated drinking water, eruptions, metal and semiconductor industry, wood preservatives
*Tasteless and odorless
*seafood arsenic felt to be organic form which is NONTOXIC and cleared from body in few days
*Organic trioxide form used as chemotherapeutic agent  
*readily absorbed via GI tract and inhalation, poorly via skin  
*Trivalent form, As3+, is toxic to over 200 intracellular enzymes  
*organic trioxide form used as chemotherapeutic agent  
*Known carcinogen: skin, lung, other  
*trivalent form, As3+, is toxic to over 200 intracellular enzymes  
*Ingestion fatal dose: 100-200mg
*known carcinogen: skin, lung, other  
 
*ingestion fatal dose: 100-200mg
===Sources of Exposure===
*Poisoning
*Contaminated drinking water
*Eruptions
*Metal and semiconductor industry
*Wood preservatives
*''seafood arsenic (felt to be organic form which is NONTOXIC and cleared from body in few days)''


==Clinical Features==
==Clinical Features==
#Acute ingestion
[[File:arsenicrash.png|thumb|Typical rash associated with chronic exposure]]
##GI symptoms  
===Acute ingestion===
##pulmonary edema
*Garlic smell of breath and tissues
##shock
*GI symptoms that can resemble [[cholera]]
##rhabdomyolysis
**Vomiting may be bloody
##sz
**"Rice water" like diarrhea
##coma
*Dehydration
##death
*[[Pulmonary Edema]]
##cardiovascular instability  
*[[Shock]]
##Arsine gas exposure: hemolysis causing abdominal pain, hematuria, jaundice
*[[Rhabdomyolysis]]
#Subacute or chronic poisoning
*[[Altered mental status]]
##anemia
*[[Seizure]]
##sensory motor neuropathy
*[[Coma]]
##skin changes
*Death
##ataxia
*Cardiovascular instability
##CNS depression
[[File:Meeslines.png|thumb|"Mees lines"]]
===Arsine gas exposure===
*Hemolysis causing abdominal pain
*[[Hematuria]], urine often looks black
*[[Jaundice]]
*Shaking chills
*Can lead to [[altered mental status]]
*Immediately lethal at 250 ppm


==Workup==
===Subacute or chronic poisoning===
*urine arsenic level (usual normal level is <50mcg/L); both urine spot test and 24h urine collection
*[[Anemia]]
*blood arsenic level not helpful (cleared within 2 hrs of exposure)
*Peripheral neuropathy
*ECG to eval for QT prolongation in acute exposure
**Typically symmetric "glove and stocking" distribution
*CBC to eval for hemolysis
*Skin changes
*BMP, Mg, phos, Ca, LFTs, CK, type and screen
*White lines on the finger nails known as "Mees lines"
*CXR if respiratory symptoms 
*[[Ataxia]]
*[[CNS Depression]]
*Risk factor for [[squamous cell carcinoma]]


==Treatment==
==Differential Diagnosis==
*supportive care, ABCs, IV, O2, monitor  
{{Heavy metals list}}
*removal from exposure  
{{Diarrhea DDX}}
*NO charcoal- adsorbs poorly to arsenic
 
*consider whole bowel irrigation if large radiopaque material in GI tract on xray 
==Evaluation==
*airway management and mechanical ventilation if acute inhalation of arsine gas and resp distress  
===Workup===
*Urine arsenic level
*[[ECG]] to eval for [[QT Prolongation]] in acute exposure
*CBC and retic count, expect hemolytic anemia
*BMP, Mg, Phos, Ca, LFTs, CK
*Type and screen for possible transfusion in arsine gas exposure
*[[CXR]] if respiratory symptoms 
*Consider other ingestion labs including acetaminophen and salicylate level in intentional ingestions
 
===Diagnosis===
*Urine arsenic level (usual normal level is <50mcg/L); both urine spot test and 24h urine collection
**Lab must differentiate inorganic from organic arsenic (treat for inorganic exposure only)
*Blood arsenic level not helpful (cleared within 2 hrs of exposure)
 
==Management==
*Supportive care, ABCs, IV, O2, monitor  
*Removal from exposure  
*NO [[Charcoal]] if co-ingestion is not suspected - adsorbs poorly to arsenic
*Consider [[Whole Bowel Irrigation]] if large radiopaque material in GI tract on xray
*Airway management and mechanical [[ventilation]] if acute inhalation of arsine gas and respiratory distress  
*IV fluids  
*IV fluids  
*CHELATION&nbsp;therapy: if severe symptoms present.
*CHELATION therapy: if severe symptoms present
 
*[[Dimercaprol]] (BAL). 3-5mg/kg IM Q4-6h
#Dimercaprol (BAL). 3-5 mg/kg IM&nbsp;Q4-6h


==Disposition==
==Disposition==
*admit pt's with significant symptoms
===Admission===
*ED&nbsp;observation and discharge with follow-up for mildly symptomatic pts
*Admit patient to intensive care setting if symptomatic from acute exposure
===Discharge===
*Asymptomatic/mildly symptomatic patients or those with suspected chronic exposures may be discharged w/ outpatient follow-up after initial ED observation.


==Sources==
==See Also==
Harwood-Nuss, EMedicine
*[[Toxicology (Main)]]
*[[Heavy Metals]]


[[Category:Tox]]
==References==
<references/>
[[Category:Toxicology]]

Latest revision as of 01:24, 16 September 2021

Background

  • Heavy metal
  • Readily absorbed via GI tract and inhalation, poorly via skin
  • Tasteless and odorless
  • Organic trioxide form used as chemotherapeutic agent
  • Trivalent form, As3+, is toxic to over 200 intracellular enzymes
  • Known carcinogen: skin, lung, other
  • Ingestion fatal dose: 100-200mg

Sources of Exposure

  • Poisoning
  • Contaminated drinking water
  • Eruptions
  • Metal and semiconductor industry
  • Wood preservatives
  • seafood arsenic (felt to be organic form which is NONTOXIC and cleared from body in few days)

Clinical Features

Typical rash associated with chronic exposure

Acute ingestion

"Mees lines"

Arsine gas exposure

Subacute or chronic poisoning

Differential Diagnosis

Acute diarrhea

Infectious

Noninfectious

Watery Diarrhea

Traveler's Diarrhea

Evaluation

Workup

  • Urine arsenic level
  • ECG to eval for QT Prolongation in acute exposure
  • CBC and retic count, expect hemolytic anemia
  • BMP, Mg, Phos, Ca, LFTs, CK
  • Type and screen for possible transfusion in arsine gas exposure
  • CXR if respiratory symptoms 
  • Consider other ingestion labs including acetaminophen and salicylate level in intentional ingestions

Diagnosis

  • Urine arsenic level (usual normal level is <50mcg/L); both urine spot test and 24h urine collection
    • Lab must differentiate inorganic from organic arsenic (treat for inorganic exposure only)
  • Blood arsenic level not helpful (cleared within 2 hrs of exposure)

Management

  • Supportive care, ABCs, IV, O2, monitor
  • Removal from exposure
  • NO Charcoal if co-ingestion is not suspected - adsorbs poorly to arsenic
  • Consider Whole Bowel Irrigation if large radiopaque material in GI tract on xray
  • Airway management and mechanical ventilation if acute inhalation of arsine gas and respiratory distress
  • IV fluids
  • CHELATION therapy: if severe symptoms present
  • Dimercaprol (BAL). 3-5mg/kg IM Q4-6h

Disposition

Admission

  • Admit patient to intensive care setting if symptomatic from acute exposure

Discharge

  • Asymptomatic/mildly symptomatic patients or those with suspected chronic exposures may be discharged w/ outpatient follow-up after initial ED observation.

See Also

References

  1. Marx et al. “Cholera and Gastroenteritis caused by Noncholera Vibrio Species”. Rosen’s Emergency Medicine 8th edition vol 1 pg 1245-1246.