RESUMO
Background Psoriasis is a common chronic inflammatory disorder affecting all aspects of a patient's life. Nail involvement is frequent, but little is known about its associated inflammatory biomarker profile, including similarities or differences from cutaneous disease. Aims We conducted this cross-sectional study to evaluate serum levels of inflammatory cytokines [tumour necrosis factor-alpha (TNF-α) and interleukin -17 (IL-17)] in patients with nail psoriasis and compared these to psoriasis patients without nail involvement, as well as in non-psoriatic healthy controls. Methods Adult psoriasis patients with (Group I, n = 30) and without nail involvement (Group-II, n = 30) were sequentially recruited. In addition, non-psoriatic healthy controls (Group-III, n = 20) were recruited. The nail disease severity by NAPSI score was determined for patients in Group I. Cutaneous disease severity (by PASI score) and presence of psoriatic arthritis (through CASPAR criteria) were evaluated for patients in Groups I and II. Serum levels of TNF-α, IL-17, erythrocyte sedimentation rate (ESR), rheumatoid factor (RA factor), and anti-cyclic citrullinated peptide antibody (Anti-CCP) were evaluated for all three groups. Results The median age was significantly higher for Group I as compared to Group II patients (41 ± 12.6 years vs 30 ± 12.4 years, p = 0.017). Group I patients also had higher median PASI score than Group II patients, although the difference was not statistically significant (10 ± 11.41 vs 6.50 ± 5.46, p = 0.275). The mean serum IL-17 levels were significantly higher for Group-I (113.39 ± 251.30 pg/mL) than Group II (27.91 ± 18.22 pg/mL, p = 0.002) and Group III (25.67 ± 12.08 pg/mL, p = 0.005). A weak positive correlation was found between NAPSI and serum IL-17 levels (Spearman's Rho = 0.355) though not statistically significant (p = 0.054). Correlation between serum IL-17 and PASI was poor for Group-I patients (Spearman's Rho = 0.13, p = 0.944) and strongly negative for Group-II patients (Spearman's Rho = -0.368, statistically significant with p = 0.045). The mean serum levels of TNF-α were below the detection threshold of the assay kit, hence no meaningful comparison could be made. Limitations A small sample size and low sensitivity of TNF-α assay kit. Conclusion Our study showed that nail psoriasis could be independently associated with an elevation of IL-17. This can help choose appropriate drugs and estimate drug response in patients with nail psoriasis.
RESUMO
Background Nail involvement in psoriasis is common and may be an indicator not only of disease severity, but also of the presence of psoriatic arthritis. However, the relationship of nail psoriasis with enthesitis remains under-explored. Aims This study was conducted to evaluate the clinical, onychoscopic (nail dermatoscopic) and ultrasonographic features in patients with nail psoriasis. Materials and Methods All nails of twenty adult patients with nail psoriasis were examined clinically and onychoscopically. Patients were evaluated for psoriatic arthritis (Classification Criteria for Psoriatic Arthritis), the severity of cutaneous disease (Psoriasis Area Severity Index) and nail disease (Nail Psoriasis Severity Index). Ultrasonography of the clinically involved digits was performed for evidence of distal interphalangeal joint enthesitis. Results Out of 20 patients, 18 patients had cutaneous psoriasis and 2 had isolated nail involvement. Among the 18 patients with skin psoriasis, 4 had associated psoriatic arthritis. The most commonly observed clinical and onychoscopic features were pitting (31.2% and 42.2%), onycholysis (36% and 36.5%) and subungual hyperkeratosis (30.2% and 30.5%), respectively. Ultrasonographic evidence of distal interphalangeal joint enthesitis was seen in 57% (175/307) of the digits with clinical nail involvement. Enthesitis was more common in patients with psoriatic arthritis (77% vs 50.6%). Nail thickening, crumbling and onychorrhexis (all features of nail matrix involvement) were significantly associated with enthesitis (P < 0.005). Limitation The major limitation was the small sample size and lack of controls. Only the clinically involved digits were evaluated for enthesitis. Conclusion Enthesitis was frequently detected on ultrasonography in patients with nail psoriasis, even in clinically asymptomatic individuals. Nail features of thickening, crumbling and onychorrhexis may predict underlying enthesitis and the potential development of arthritis. A comprehensive evaluation could help identify patients with psoriasis at risk for arthritis, helping improve long-term outcomes.
