Nail involvement features in palmoplantar pustulosis.

Area of Science:

• Dermatology
• Clinical Research
• Pathogenesis Studies

Background:

• The pathogenesis of palmoplantar pustulosis (PPP) remains unclear, with ongoing debate regarding its classification relative to plaque psoriasis (PsO).
• Nail changes are a shared clinical manifestation, offering potential insights into the relationship between PPP and PsO.
• Limited research exists on the specific patterns of nail involvement in PPP.

Purpose of the Study:

• To investigate and characterize the features of nail involvement in patients diagnosed with palmoplantar pustulosis (PPP).
• To compare the nail involvement patterns observed in PPP with those previously documented in plaque psoriasis (PsO).
• To identify potential risk factors associated with nail involvement in PPP.

Main Methods:

• Retrospective review of medical records and photographic data from patients diagnosed with PPP.
• Comparative analysis of nail involvement patterns between PPP patients and a cohort of PsO patients from a prior study.
• Statistical analysis to assess correlations between nail severity and cutaneous lesion severity, and to identify risk factors.

Main Results:

• Nail involvement was present in 66.3% of PPP patients, correlating with cutaneous lesion severity (r=0.34, P=0.01).
• Onycholysis and crumbling were more frequent in PPP than PsO; crumbling correlated with higher PPP severity (P=0.01), while onycholysis correlated with lower severity (P=0.03).
• Nail changes were less prominent in the first digits of PPP patients compared to PsO patients. Female sex (OR=9.44), younger age at diagnosis (OR=1.08), and higher disease severity (OR=1.15) were risk factors for nail involvement.

Conclusions:

• Palmoplantar pustulosis (PPP) exhibits distinct nail involvement patterns compared to plaque psoriasis (PsO), despite shared features.
• Nail changes in PPP are common and associated with disease severity, with specific features like onycholysis and crumbling showing differential prevalence.
• Understanding these nail differences aids in clarifying the relationship between PPP and PsO and identifying patients at higher risk for nail disease.