Is cryotherapy using liquid nitrogen (LN) a recommended treatment for Molluscum contagiosum?

Cryotherapy with Liquid Nitrogen for Molluscum Contagiosum

Cryotherapy with liquid nitrogen is an effective first-line treatment option for molluscum contagiosum and is recommended as a physical removal method. 1

Mechanism and Efficacy

• Cryotherapy works by causing thermal damage to infected tissue, allowing the host immune response to eliminate residual virus 1
• It is considered one of the methods of choice for the majority of patients with molluscum contagiosum 2
• When treating with cryotherapy, it's important to identify and address all lesions, including nascent ones, to reduce the risk of recurrence 1

Appropriate Application

• Cryotherapy should be applied directly to the molluscum lesions, which typically present as skin-colored, whitish, or pink papules with a shiny surface and central umbilication 3
• For genital lesions, cryotherapy with liquid nitrogen is specifically mentioned as an appropriate treatment option in guidelines 4
• Treatment may need to be repeated weekly until lesions resolve 5

Anatomical Considerations

• Caution should be exercised when using cryotherapy on certain anatomical sites:
  • The use of a cryoprobe in the vagina is not recommended due to risk of vaginal perforation and fistula formation 4
  • Cryotherapy should be avoided on the nose due to potential complications including scarring, tissue damage, and adverse cosmetic outcomes 6

Comparative Effectiveness

• In a randomized clinical trial comparing 10% potassium hydroxide solution versus cryotherapy, both treatments showed similar efficacy (93.3% complete response with cryotherapy vs. 86.6% with KOH) 5
• Physical destruction methods, particularly cryotherapy with liquid nitrogen, are considered methods of choice for the majority of patients 2

Special Populations

• For immunocompromised patients who may have more extensive and persistent lesions, cryotherapy may be used but might require more aggressive or combined approaches 7
• In pregnancy, physical procedures like cryotherapy are considered safe treatment options 8

Side Effects and Limitations

• Common side effects include erythema, swelling, vesicle formation, and burning pain 6
• Postinflammatory hyperpigmentation is a notable side effect of cryotherapy, occurring more frequently than with some other treatment modalities 5
• Both hypo- and hyperpigmentation can result from cryotherapy, with pigmentary changes typically worse and more persistent in patients with darkly pigmented skin 6

Follow-Up Recommendations

• After treatment, follow-up evaluation is not mandatory but patients should be monitored for recurrences, which occur most frequently during the first 3 months 4
• Patients concerned about recurrences should be offered a follow-up evaluation 3 months after treatment 4
• For patients with associated conjunctivitis, follow-up may be needed until the conjunctivitis resolves, which can take weeks after elimination of the lesion 1