Not a Mollusc! A Case Report about the Subepidermal Calcified Nodule of Winer

Introduction

Calcinosis cutis is defined as the abnormal deposition of insoluble calcium salts within the skin and subcutaneous tissues. It is broadly classified into dystrophic, metastatic, idiopathic, iatrogenic, and calciphylactic subtypes, based on underlying etiology [1], [2]. While dystrophic calcification occurs in damaged tissue with normal serum calcium and phosphate levels, metastatic calcification arises in the setting of systemic mineral imbalance, such as hypercalcemia or hyperphosphatemia [3].

A rare idiopathic variant of calcinosis cutis is the Subepidermal Calcified Nodule (SCN), which was first described by Winer in 1952 [4]. SCN typically presents as a solitary, firm, asymptomatic, white or skin-colored papule or nodule, most often on the face or extremities of healthy infants, children, or young adults [4] [5] [6] [7]. Although the exact pathogenesis is unclear, localized tissue injury, degeneration, or abnormalities in dermal calcium handling have been proposed as possible contributing factors [8]. The subepidermal form of calcinosis of Winer is particularly uncommon and may mimic a variety of more common dermatologic or soft tissue conditions, such as epidermoid cysts, lipomas, or granulomatous lesions.

Surgical excision remains the preferred treatment, providing both therapeutic resolution and tissue for definitive diagnosis [5], [7], [10].

This case report presents a pediatric patient with subepidermal calcinosis of Winer and highlights the importance of ruling out metabolic causes of cutaneous calcification while addressing common clinical mimickers.

Publication History

Received: 01 November 2025

Accepted: 23 December 2025

Article published online:
11 February 2026

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