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Disorder characterized by vasodilatation associated
with paroxysmal, intense burning pain and episodic reddening of the
extremities (mainly feet). The symptoms of redness, heat, pain, and
swelling, when not associated with an organic disease, constitute the
primary form, which has also been termed “erythermalgia” because of the
significance of the heat. The secondary or acquired form is related to
underlying medical conditions.
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Acromelalgia; Erythermalgia; Gerhardt Disease;
Weir-Mitchell Disease.
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The first case was reported by the Irish physician Richard
James Graves in 1834. The American physician Silas Weir Mitchell suggested
the term “Erythromelalgia” in 1878, and the German physician Carl Jakob
Gerhardt provided further insights into erythromelalgia in 1892.
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Approximately 0.25:100,000 in the general population.
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Autosomal dominant inheritance for primary
erythromelalgia susceptibility, with the responsible gene located on
chromosome 2q31-32.
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Pathogenesis unknown. Proposed mechanisms involve
abnormalities in platelet aggregation, with contributing factors such as
vessel wall damage, changes in blood flow patterns, and disturbances in
prostaglandin metabolism. Intravascular platelet aggregation appears to play
a major role. Endothelial cells in affected areas appear swollen with
enlarged nuclei. Smooth muscle cell proliferation and vacuolization of the
cytoplasm in the tunica media of the vessels and deposition of interstitial
collagen lead to narrowing of the vessels lumen. The internal elastic lamina
seems to be split between the proliferated smooth muscle cells resulting in
a picture of fibromuscular intimal proliferation, which is (with or without
occlusive intravascular thrombosis) a specific erythromelalgia finding.
Arterioles are frequently occluded by thrombi rich in platelets or which
become completely fibrotic in the presence of peripheral necrosis.
Immunofluorescence findings have failed to indicate a specific inflammatory
process. It seems therefore that erythromelalgia is not a separate disease
entity but rather a pathophysiologic response (microvascular arteriovenous
shunting) of the skin microcirculation, with shunting induced by opening of
anatomical arteriovenous anastomosis normally present in hands, feet, nose,
and ears, or by angioneogenesis.
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Primary and secondary/acquired types occurred. The
primary type occurs in children, especially boys, whereas the secondary form
is found almost entirely in adults who have an underlying disease (typically
polycythemia vera, essential thrombocythemia, chronic myelogenous leukemia,
and idiopathic myelofibrosis and other forms of myeloproliferative
disorders) but may also include connective tissue disorders, autoimmune
collagen vascular diseases (e.g., rheumatoid arthritis, Systemic Lupus
Erythematosus (SLE)), infectious diseases (e.g., AIDS), neurologic diseases (e.g.,
multiple sclerosis, neuropathies), cardiovascular disorders (e.g., arterial
hypertension, arteriosclerosis), diabetes mellitus, and drugs (e.g., iodine
contrast injection, vaccinations, calcium antagonists). The clinical
appearance of both primary and secondary forms is basically identical. The
pathognomonic diagnostic criterion of secondary erythromelalgia is rapid
pain relief that lasts a few days after one low dose of aspirin, which
irreversibly inhibits platelet cyclooxygenase activity. Heat intolerance
(and aggravation of symptoms with standing or exercise) and relief of
symptoms with cooling (and elevation of the affected body part and rest) are
hallmarks of erythromelalgia, whereas warmth exposure not only triggers
flaring ...