Acrodynia

Acrodynia is a medical condition which occurs due to mercury poisoning. The condition of pain and dusky pink discoloration in the hands and feet is due to exposure or ingesting of mercury. It was known as pink disease (due to these symptoms) before it was accepted that it was just mercury poisoning. The word acrodynia is derived from the , which means end or extremity, and , which means pain. As such, it might be (erroneously) used to indicate that a patient has pain in the hands or feet. The condition is known by various other names including hydrargyria, mercurialism, erythredema, erythredema polyneuropathy, '''Bilderbeck's, Selter's, Swift's and Swift-Feer disease'''.

==Symptoms and signs== Besides peripheral neuropathy (presenting as paresthesia or itching, burning or pain) and discoloration, swelling (edema) and desquamation may occur. Since mercury blocks the degradation pathway of catecholamines, epinephrine excess causes profuse sweating (diaphora), tachycardia, salivation and elevated blood pressure. Mercury is suggested to inactivate S-adenosyl-methionine, which is necessary for catecholamine catabolism by catechol-o-methyl transferase. Affected children may show red cheeks and nose, red (erythematous) lips, loss of hair, teeth, and nails, transient rashes, hypotonia and photophobia. Other symptoms may include kidney dysfunction (e.g. Fanconi syndrome) or neuropsychiatric symptoms (emotional lability, memory impairment, insomnia).