# Progressive Thickening of the Fingers in Adolescence: A Case Report of a Rare Entity

## TL;DR

A 16-year-old male with progressive finger thickening was diagnosed with pachydermodactyly, a rare benign condition often mistaken for other disorders.

## Contribution

This case report highlights the importance of early recognition of pachydermodactyly to avoid unnecessary diagnostic procedures.

## Key findings

- Histopathology confirmed transgressive pachydermodactyly with fibrous dermal hyperplasia and epidermal changes.
- Conservative treatment with topical corticosteroids stabilized the condition.
- The patient's history of repetitive mechanical exposure may be a contributing factor.

## Abstract

Pachydermodactyly (PPD) is a rare, benign digital fibromatosis that predominantly affects adolescent males and can mimic inflammatory or rheumatologic disorders. We report a case of a 16-year-old male with a six-year history of painless, progressive periarticular thickening of the hands and feet, primarily involving the second through fourth interphalangeal joints. The patient reported repetitive mechanical exposure associated with basketball and video game use. Laboratory studies, imaging, and a skin biopsy were performed to exclude alternative diagnoses. Histopathology demonstrated fibrous dermal hyperplasia, epidermal acanthosis with hyperkeratosis, and increased stromal mucins, consistent with transgressive PPD. Conservative management with topical corticosteroids resulted in stabilization of the disease. Early recognition of this entity is essential to avoid unnecessary investigations and inappropriate treatment, particularly in adolescents, for whom cosmetic concerns may significantly affect quality of life.