A Cross-Sectional Study of Nailfold Capillary Changes in Psoriasis

BACKGROUND: Microcirculation in the skin of psoriasis patients significantly differs from unaffected individuals. Vascular changes precede skin lesions and occur even in nonlesional skin. AIMS: The primary aim of this work was to study the nailfold capillary changes in psoriasis patients, and to compare it with that of controls. The secondary aim of this work was to compare the nailfold capillary changes in psoriasis patients with and without nail changes. METHODS: A comparative cross-sectional study of 40 psoriasis patients and 40 age and sex-matched controls analyzed the capillaries of the proximal nailfold of all fingers using a dermoscope. The mean capillary loop density/mm, tortuous capillaries, capillary hemorrhages, and avascular areas were assessed. RESULTS: The mean nailfold capillary loop density in psoriasis (6.98 ± 0.54 per mm) was significantly less than that in controls (8.01 ± 0.61 per mm) (P < 0.001). Avascular areas in the nailfold of psoriasis patients (55%) were significantly more than the same in controls (22.5%) (P = 0.003). Of 40 psoriasis patients, 26 had nail psoriasis. Of this, 19 (73%) had avascular areas (P = 0.002). No significant association of nailfold capillary density or avascular areas with disease duration or severity was noted. An increase in tortuous capillaries and nailfold hemorrhages noted in psoriasis was not significant. LIMITATIONS: Small sample size, not having participants with psoriatic arthropathy, and lack of information on capillary diameter and capillary changes in hyponychium were the limitations. CONCLUSION: The reduced mean capillary loop density, and higher frequency of avascular areas noted in cases compared to controls, points to a pathogenic role for microvascular damage in psoriasis. Whether the lack of association of these changes with disease duration and severity suggests the possibility of these being early disease markers for psoriasis, needs further analysis in larger prospective studies.