Arsenic poisoning

Presentation

Acute cases present with garlic breath, vomiting, watery diarrhea, and QTc prolongation. If severe, there can be pancytopenia and hepatitis.

Chronic cases present with:

sensorimotor neuropathy -- stocking glove distribution with burning sensation, distal weakness, hyporeflexia
skin changes -- 1. first there is a change in skin color (hypo/hyperpigmentaiton), 2. later hyperkeratosis (scaling of palms/ soles), 3. Mees lines (horizontal lines on fingernails)

Pathology

Arsenic binds to sulfhydryl groups and disrupts cellular respiration and gluconeogenesis.

Sources of arsenic include pesiticides/ insecticides, contaminated water (e.g. well water), and pressure treated wood (e.g. antique furniture).

Diagnosis

Urine arsenic levels

Treatment

Chelation therapy with:

Dimercaprol (British anti-Lewisite, BAL)
DMSA (meso-2,3-dimercaptosuccinic acid, succimer)

Relevant Images

Dimercaprol has sulfhydryl groups and arsenic binds to them:

Comments

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Chemotherapy

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pathology

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