Cryotherapy Unmasks Umbilication in Molluscum Contagiosum

Case Presentation

Molluscum contagiosum (MC) is a viral skin disease caused by the Molluscum contagiosum virus [1]. The virus is characterized by high infectious potential and may be transmitted via direct contact, using fomites, or due to autoinoculation [1]. Clinically, MC usually manifests as multiple pearl-whitish shiny papules with the umbilicated center, although solitary lesions may be observed [1]. On dermoscopy, typical features can be seen, mainly a central white-yellowish amorphous areas, surrounded by blurry crowned vessels on the periphery [2]. Solitary lesions represent a clinical challenge, especially in cases where umbilication is not evident (Figure 1A), and in cases with confusing dermoscopic findings. What else can aid diagnosis in these cases, apart from histopathological examination?

Figure 1.

Molluscum contagiosum. (A) A solitary, non-umbilicated lesion before administration of treatment. (B) On the right: umbilicated center appears after administration of cryotherapy.

Teaching Point

Cryotherapy is a practical and cost-effective solution to this problem. After administration of a short cycle of liquid nitrogen to a lesion with an inconspicuous umbilicated center, the concavity appears instantly, confirming the diagnosis of molluscum contagiosum (Figure 1B). Cryotherapy is widely available in every dermatology department, moreover, it is a non-invasive technique and it does not require much time to perform or to recover after the procedure. Hence, in doubtful monolesional non-umbilicated cases, it improves the diagnostic efficacy.