Computer assisted evaluation of skin capillary density supports the hypothesis of microvascular shunting in erythromelalgia
(English)Manuscript (preprint) (Other academic)
Erythromelalgia subjects often suffer from burning pain in distal parts of the extremities, aggravated by warmth and relieved by cooling. Affected skin is hyperemic and has an increased skin temperature. The shunting hypothesis for the pathogenesis of erythromelalgia, postulates maldistribution of skin microvascular blood flow with increased thermoregulatory flow through arteriovenous shunts and an inadequate nutritive perfusion with a corresponding tissue hypoxia. Our aim was to characterize recruitment and steal distribution changes in affected skin with the aid of an enhanced technique of computer-assisted analysis of capillary beds. This method was used to determine the capillary density before and after central body heating in 14 patients with erythromelalgia and 10 controls. Symptoms were induced in 8 patients and their skin temperature became higher (p<0.05) after central body heating, but the number of visible or active capillaries in the dorsal aspect of the foot decreased significantly, as compared to asymptomatic patients and controls. Since the increased temperature should, normally induce capillary recruitment, and other studies using laser Doppler techniques have shown an increase in global skin perfusion during EM attacks, we conclude that the reduced capillary density shown in this study, is compatible with the hypothesis of blood shunting through AV anastomoses, deep in the dermis.
Medical and Health Sciences
IdentifiersURN: urn:nbn:se:liu:diva-89591OAI: oai:DiVA.org:liu-89591DiVA: diva2:608391