%0 Journal Article %T Capillaroscopy in Psoriatic and Rheumatoid Arthritis: A Useful Tool for Differential Diagnosis %A Dario Graceffa %A Beatrice Amorosi %A Elisa Maiani %A Claudio Bonifati %A Maria Sole Chimenti %A Roberto Perricone %A Aldo Di Carlo %J Arthritis %D 2013 %I Hindawi Publishing Corporation %R 10.1155/2013/957480 %X Impairment of capillaries permeability and changes of microcirculation are associated with inflammatory arthritis. In order to demonstrate microvascular differences between psoriatic arthritis (PsA) and rheumatoid arthritis (RA) we analyzed capillaroscopic abnormalities such as megacapillaries, haemorrhages, ramifications, and avascular areas in patients affected by these two rheumatic disorders. Moreover to identify specific capillaroscopy patterns we analyzed the following parameters: venous limb diameter, arterial limb diameter, capillary loop diameter, amplitude of the capillary loop, linear density of capillaries (on 2£żmm), and number of twisted capillaries (on 4£żmm). Through a comparative morphometric analysis of capillaroscopy, our study demonstrated the presence of specific microvascular differences between PsA and RA providing an additional diagnostic tool for the differential diagnosis. We also suggest that capillaries structural abnormalities might reflect endothelial injury due to systemic inflammation during chronic arthritis. 1. Introduction Psoriatic arthritis (PsA) is a chronic inflammatory disease affecting 0.04%¨C0.1% of the general population and occurs in one-third of patients with psoriasis. PsA can lead to severe bone erosions and joints destruction resulting in physical disability [1]. Nowadays, no specific laboratory tests are available for PsA; it is not always possible, therefore, confirm the diagnosis and provide an objective prognosis, especially at an early stage of disease. The differential diagnosis between PsA and RA is very difficult in PsA patients with slight cutaneous signs and rheumatoid-like joint involvement [2¨C4]. Presence of citrullinated peptide antibodies has a high specificity for RA, but, among that, they are rarely seen in PsA patients [5]. Morphological and rheological changes in microcirculation have been widely demonstrated in PsA and RA patients. Impairment of capillaries permeability and alterations in the connections between endothelium and extracellular matrix characterize these damages, resulting in abnormal structure and shape of the capillaries in the dermal papillae [6¨C8]. Capillaroscopy allows the study Ħ°in vivoĦħ of morphological and functional characteristics of microcirculation. Several authors have tried to identify specific microvascular characteristics of cutaneous psoriasis and PsA; these studies were mainly conducted on the skin plaques, on synovial membrane and at nailfold level. However, the results are not univocal [9¨C12]. Aim of our study was to demonstrate specific microvascular %U http://www.hindawi.com/journals/arthritis/2013/957480/