The Brazilian Portuguese version of the psoriasis epidemiology screening tool (PEST-bp) is reliable and accurate: a cross-sectional study from southern Brazil

TL;DR

A new tool for detecting psoriatic arthritis in Brazil is found to be reliable and accurate.

Contribution

The study validates the diagnostic accuracy of the Brazilian Portuguese version of the PEST tool for PsA detection.

Findings

A PEST-BP score ≥ 3 showed 81% sensitivity and 79.7% specificity for PsA detection.

PsA patients had higher prevalence of dactylitis, nail psoriasis, and PASI ≥ 10.

PEST-BP score ≥ 3 and PASI ≥ 10 were independently associated with PsA in multivariate analysis.

Abstract

Psoriatic arthritis (PsA) remains diagnostically challenging in clinical practice. The Psoriasis Epidemiology Screening Tool - Brazilian Portuguese version (PEST-BP) offers a potential solution for simplified case identification.

To evaluate the diagnostic accuracy of PEST-BP in detecting PsA among patients with psoriasis in a novel Southern Brazilian population.

In this cross-sectional study, psoriasis patients from a dermatology clinic underwent dual assessment: PEST-BP screening and gold-standard rheumatologic evaluation using CASPAR criteria for PsA diagnosis. Statistical analyses included sensitivity, specificity, and ROC curve determination.

Among 100 patients, 21 (21%) met the CASPAR criteria for PsA. A PEST-BP score ≥ 3 showed the best diagnostic performance with 81% sensitivity, 79.7% specificity, and 80% overall accuracy (AUC = 0.845, p < 0.001). Patients with PsA had a significantly higher prevalence of dactylitis (38.1% vs. 11.4%; p = 0.004), nail psoriasis (66.7% vs. 35.4%; p = 0.01), and Psoriasis Area and Severity Index (PASI) ≥ 10 (42.9% vs. 19%; p = 0.023). In multivariate analysis, a PEST-BP score ≥ 3 (OR = 32.43; p < 0.001) and PASI ≥ 10 (OR = 9.26; p = 0.007) were independently associated with PsA.

Single-center design in a tertiary care hospital and small sample size may overrepresent patients with severe disease.

The PEST-BP is a reliable and accurate tool for PsA screening in Brazilian dermatology settings. Its simplicity and strong diagnostic performance support its integration into routine clinical practice for early PsA detection.

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