Introduction Demographics Causes Clinical features Variation in skin types Complications Diagnosis Differential diagnoses Treatment Outcome
Subepidermal calcified nodules are deposits of insoluble calcium or phosphorus in the skin. Also known as Winer’s nodular calcinosis or solitary congenital nodular calcification, they are a subtype of calcinosis cutis.
Subepidermal calcified nodules are typically found in children, although almost 30% of cases have been reported in adults. They are relatively rare with only a few hundred cases reported. They are twice as common in men as in women.
As a type of idiopathic calcinosis cutis, subepidermal calcified nodules are of unclear aetiology. While suggested to be a form of dystrophic calcification, controversy remains over the exact mechanism.
They occur in supposedly undamaged skin (although some have suggested that unappreciated trauma may be responsible), in patients with normal serum calcium, phosphate, and parathyroid hormone levels.
Difficult to differentiate from other cutaneous nodules via general examination, dermoscopy reveals yellow-white clods, surrounded by linear vessels.
A firm, mobile, asymptomatic nodule is characteristic in case reports of subepidermal calcified nodules in different skin types, with no specific differences observed.
Subepidermal calcified nodules are benign lesions, although they may cause both cosmetic concerns or local irritation and pain.
As clinical examination often leads to misdiagnosis, histology may be the only way of confirming diagnosis.
Histologically, subepidermal calcified nodules show:
Recently, reflectance confocal microscopy (RCM) has also been suggested as a potential diagnostic tool.
Lesions can be managed expectantly if asymptomatic, or can be surgically excised. Excision usually results in complete removal without recurrence.
Curettage, laser, salicylic acid, and intralesional triamcinolone have all been described.
Subepidermal calcified nodules are benign. If elective excision is chosen, almost always for cosmetic reasons or pain, outcomes are excellent and recurrence has not been described.
