# Exploring Patterns of Palmar Hyperlinearity in Pediatric Population With Atopic Dermatitis or Ichthyosis Vulgaris Attending a Tertiary Care Hospital in Jaipur, India

## TL;DR

This study explores how palmar hyperlinearity patterns differ in children with atopic dermatitis or ichthyosis vulgaris in India.

## Contribution

The study identifies distinct palmar hyperlinearity patterns associated with atopic dermatitis and ichthyosis vulgaris in a pediatric population.

## Key findings

- Hyperlinear patterns were observed in 58.7% of the 206 participants.
- Frequent cross-hatch patterns were most common in atopic dermatitis cases.
- Thick perpendicular lines were most prevalent in ichthyosis vulgaris-only cases.

## Abstract

Introduction: Ichthyosis vulgaris (IV) and atopic dermatitis (AD) are skin diseases occurring in children and having important quality-of-life implications. Palmar hyperlinearity has been characterized as a visible sign of skin barrier abnormality in these disorders.

Methods: In this hospital-based cross-sectional study, children aged six months to 18 years with a confirmed diagnosis of AD, IV, or both were assessed for five pre-defined palmar patterns. Patterns were graded as hyperlinear or non-hyperlinear, and their correlation with disease groups was examined. Inter-rater reliability was evaluated in a subset.

Results: Out of the 206 recruited participants, 121 children (58.7%) had hyperlinear patterns. Frequent cross-hatch was the most common hyperlinear pattern overall, found in relation to isolated AD predominantly. Thick perpendicular lines were most prevalent in IV-only cases, and frequent diamond patterns occurred in children with both AD and IV. Classification was found to have considerable inter-observer agreement (Fleiss Kappa statistic= 0.62).

Conclusions: Patterns of palmar hyperlinearity in AD and IV are different. Detection can be a low-cost adjunct for the early diagnosis and phenotyping, particularly in cases where genetic analysis is not accessible.