Arsenic toxicity: Difference between revisions
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==Differential Diagnosis== | ==Differential Diagnosis== | ||
*[[Heavy metals]] | |||
**[[Iron]] | |||
**[[Mercury]] | |||
===[[Acute diarrhea]]=== | |||
==== Infectious ==== | |||
*Viral (e.g. rotavirus) | |||
*Bacterial | |||
**[[Campylobacter]] | |||
**[[Shigella]] | |||
**[[Salmonella]] (nontyphi) | |||
**[[Escherichia coli]] | |||
***E. coli 0157:H7 | |||
**[[Yersinia enterocolitica]] | |||
**[[Cholera|Vibrio cholerae]] | |||
**[[Clostridium difficile]] | |||
*[[Parasitic]] | |||
**[[Giardia lamblia]] | |||
**[[Cryptosporidium]] | |||
**[[Amebiasis|Entamoeba histolytica]] | |||
*Toxin | |||
**[[Staphylococcus aureus]] | |||
**[[Bacillus cereus]] | |||
==== Noninfectious ==== | |||
*[[GI Bleed]] | |||
*[[Appendicitis]] | |||
*[[Mesenteric Ischemia]] | |||
*[[Diverticulitis]] | |||
*[[Adrenal Crisis]] | |||
*[[Thyroid Storm]] | |||
*[[Toxidromes|Toxicologic exposures]] | |||
*Antibiotic or drug-associated | |||
====Watery Diarrhea==== | |||
* Enterotoxigenic [[E. coli] | |||
* Norovirus (often has prominent vomiting) | |||
* Campylobacter | |||
* Non-typhoidal [[Salmonella]] | |||
* Enteroaggregative E. coli (EAEC) | |||
* Enterotoxigenic [[Bacteroides fragilis]] | |||
====[[Traveler's Diarrhea]]==== | |||
*[[Giardia lamblia]] | |||
*[[Cryptosporidiosis]] | |||
*[[Entamoeba histolytica]] | |||
*[[Cyclospora]] | |||
==Diagnosis== | ==Diagnosis== |
Revision as of 20:06, 20 October 2015
Background
- Heavy metal
- 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
- readily absorbed via GI tract and inhalation, poorly via skin
- 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
Clinical Features
Acute ingestion
- GI symptoms that can resemble cholera
- Vomiting may be bloody
- "rice water" like diarrhea
- dehydration
- Pulmonary Edema
- Shock
- Rhabdomyolysis
- altered mental status
- Seizure
- coma
- death
- cardiovascular instability
Arsine gas exposure
- hemolysis causing abdominal pain
- hematuria, urine often looks black
- jaundice
- shaking chills
- can lead to altered mental status
Subacute or chronic poisoning
- Anemia
- peripheral neuropathy
- typically symmetric "glove and stocking" distribution
- skin changes
- White lines on the finger nails known as "Mees lines"
- ataxia
- CNS Depression
Differential Diagnosis
Acute diarrhea
Infectious
- Viral (e.g. rotavirus)
- Bacterial
- Campylobacter
- Shigella
- Salmonella (nontyphi)
- Escherichia coli
- E. coli 0157:H7
- Yersinia enterocolitica
- Vibrio cholerae
- Clostridium difficile
- Parasitic
- Toxin
Noninfectious
- GI Bleed
- Appendicitis
- Mesenteric Ischemia
- Diverticulitis
- Adrenal Crisis
- Thyroid Storm
- Toxicologic exposures
- Antibiotic or drug-associated
Watery Diarrhea
- Enterotoxigenic [[E. coli]
- Norovirus (often has prominent vomiting)
- Campylobacter
- Non-typhoidal Salmonella
- Enteroaggregative E. coli (EAEC)
- Enterotoxigenic Bacteroides fragilis
Traveler's Diarrhea
Diagnosis
- urine arsenic level (usual normal level is <50mcg/L); both urine spot test and 24h urine collection
- blood arsenic level not helpful (cleared within 2 hrs of exposure)
- ECG to eval for QT Prolongation in acute exposure
- CBC to eval for hemolysis
- BMP, Mg, phos, Ca, LFTs, CK, type and screen
- CXR if respiratory symptoms
Treatment
- supportive care, ABCs, IV, O2, monitor
- removal from exposure
- NO Charcoal - 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 resp distress
- IV fluids
- CHELATION therapy: if severe symptoms present
- Dimercaprol (BAL). 3-5 mg/kg IM Q4-6h
Disposition
- admit pt's with significant symptoms
- ED observation and discharge with follow-up for mildly symptomatic