Capillaroscopy in psoriasis vulgaris - Journal of the European Academy of Dermatology and Venereology 1996;7(2):192-193

Marcia Ramos-e-Silva, MD, PhD1
Edda Bernardini, MD, PhD2
Absalom Lima Filgueira, MD, PhD3

From the Postgraduate Course in Dermatology, School of Medicine and HUCFF, at the Universidade Federal do Rio de Janeiro. Supported in part by Coordenação de Aperfeiçoamento de Pessoal de Ensino Superior, Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro and Fundação Smith-Kline.

1. Associate Professor (Dermatology)
2. Associate Professor (Angiology)
3. Professor (Dermatology)

To the Editor: Capillaroscopy of proximal nail fold of the fingers is a method of observation of superficial cutaneous vessels, which reflects, in general, the condition of capillaries of the whole organism.

Capillaroscopy studies of the lesions 1,2,3,4,5 and apparently normal skin of psoriatic patients 2,6 only permit the examination of the top of capillary loops, showing dilatation, twisting and winding around their apices. However, when this method is used to observe capillaries of the proximal nail fold of a finger it can be of more value as it allows, in addition, observation of afferent and efferent limbs, venal plexus and actual blood flow.

In order to test the method, twenty patients with psoriasis vulgaris and an age-matched control group had their proximal nail folds examined. Smokers and individuals with high blood pressure or diabetes were not included. The observed parameters were: 1) field: color, visibility, presence of edema, appearance of the venular plexus and hemorrhage; 2) afferent and efferent limbs: size, number, configuration, color and presence of microectasia; 3) flow: type and speed. For statistical analysis logistic linear regression method 7 was used.

Our investigation concluded that, at the proximal nail fold, twisting* and dilatation** of venular branches of the capillary limb occur with a significant greater frequency in psoriatic patients than in normal individuals (Table 1* and 2**). No significant statistical difference was found in any other parameter. These findings agree with the capillary alteration already noted under optical and electron microscopy in both compromised 8 and apparently normal skin 9, confirming that all the skin is altered by psoriasis.

The presence of twisted and dilated venular branches in the nail fold can be considered a capillaroscopic standard for psoriasis vulgaris. The definition of this standard, established by our study, is extremely important as the characteristics found in nail fold (dilatation and twisting of efferent limb), although not pathognomonic, can be used to help the diagnosis of this disease in cases where clinical aspects and histopathology are not conclusive. To our knowledge and after an exhaustive review of the literature we believe that this study is the first to evaluate the microcirculatory component in psoriasis vulgar using nail fold capillaroscopy, in comparison with a control group and with a statistical evaluation of the frequency of the findings. Proximal nail fold capillaroscopy may be recommended as an useful accessory method in the diagnosis of atypical or difficult cases of psoriasis.

TABLE 1. Capillaroscopy of the nail fold in psoriatic and control group
Distribution according to shape of the efferent limb.

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