Molluscum contagiosum (MC) is a common skin disease caused by a poxvirus, primarily affecting children and immunocompromised individuals. Its incidence rate is approximately 1–2 cases per 1,000 people annually in the United States, with higher rates in tropical regions. The virus spreads through direct skin-to-skin contact or via shared objects like towels. MC typically presents as discrete, smooth, pearly or flesh-colored dome-shaped papules, often with a central umbilication. While the diagnosis is usually clinical, in atypical cases or when differentiation from other skin lesions is challenging, dermatoscopy plays a significant role. Dermatoscopy offers a non-invasive, rapid, and accurate diagnostic method, helping clinicians better understand the skin lesion structure and improving diagnostic accuracy.
What Is Molluscum Contagiosum and What Are Its Clinical Features and Transmission Routes?
Molluscum contagiosum is a self-limiting skin disease caused by the molluscum contagiosum virus (MCV), a member of the poxvirus family. It commonly affects children aged 1–10 and immunocompromised individuals such as HIV patients or organ transplant recipients. MC is transmitted through direct skin contact, autoinoculation, or contact with contaminated objects like towels or clothing. Clinically, MC lesions are characterized by discrete, semi-spherical papules with a smooth surface, measuring 2–6 mm in diameter (sometimes up to 15 mm). They are typically flesh-colored, white, or pink, with a central umbilication and a waxy luster. Lesions are usually asymptomatic but may occasionally itch. In immunocompromised individuals, lesions may be larger, more numerous, and slower to resolve.
What Types of Molluscum Contagiosum Are There?
Molluscum contagiosum can be categorized into common molluscum contagiosum and genital molluscum contagiosum. Genital molluscum contagiosum is typically transmitted through sexual contact and is classified as a sexually transmitted infection. MC lesions usually have a characteristic appearance, making clinical diagnosis relatively straightforward. However, in some cases, MC may resemble other skin lesions such as basal cell carcinoma, keratoacanthoma, seborrheic keratosis, or syringoma. For example, basal cell carcinoma often presents as a pearly papule with telangiectasia, while keratoacanthoma appears as a rapidly growing, keratin-filled nodule. Dermatoscopy can help distinguish MC from these conditions. Additionally,MC may mimic other viral warts. For instance, common warts exhibit papillomatous structures with central red punctate or linear vessels under dermatoscopy, whereas flat warts show a light brown or yellow background with irregular red-brown-black dots or linear streaks.
What Are the Dermatoscopic Features of Molluscum Contagiosum?
Dermatoscopy reveals characteristic features of MC lesions. Typically, a central umbilication or crater-like depression is visible, accompanied by a white, amorphous, multilobulated structure (such as round, cloverleaf, or star-shaped white-yellow structures). Surrounding the lesion, there may be linear or branching vessels, such as crown-like, spoke-wheel, or radial vessels. The white structure corresponds to the accumulation of MC bodies within the epidermis, while the vessels are related to the inflammatory response caused by the virus. Studies have shown that dermatoscopic findings of central umbilication and white structures can help confirm MC diagnosis, with sensitivity and specificity as high as 90% and 95%, respectively. 
How Can Molluscum Contagiosum Be Differentiated from Other Skin Lesions?
Dermatoscopy aids in distinguishing MC from other skin lesions. For example, basal cell carcinoma often displays blue-gray globules, leaf-like areas, or arborizing telangiectasia under dermatoscopy; keratoacanthoma typically shows a keratin plug and peripheral telangiectasia; seborrheic keratosis exhibits a "pasted-on" appearance with horny cysts and milia-like structures; and syringoma presents as small, yellowish-brown papules with a homogeneous structure. By comparing the dermatoscopic features of MC with those of other skin lesions, clinicians can more accurately differentiate MC from other conditions, avoiding misdiagnosis and ensuring timely treatment.
How Can Dermatoscopy Images Be Utilized in the Diagnostic Process?
The IBOOLO handheld dermatoscope set is equipped with a universal phone clip. Attach the universal mobile phone clip to the mobile phone, then rotate the magnetic ring on, and finally magnetically attach the dermatoscope. After that, adjust the focus, and you can take photos or videos of the skin lesions. The dermatoscope images provide a visual reference for the diagnosis of MC. Clinical doctors can use these images to document the characteristics of the lesions, which facilitates communication with patients and enhances their understanding of the condition.
What Are the Treatment and Management Options for Molluscum Contagiosum?
Molluscum contagiosum is generally self-limiting, with lesions often resolving spontaneously within 6–18 months. However, due to its contagiousness and potential cosmetic concerns, many patients seek treatment. Common treatments include cryotherapy, curettage, laser therapy, and topical medications such as imiquimod cream and salicylic acid. The choice of treatment depends on factors like lesion location, size, and patient age. For example, cryotherapy and curettage are suitable for localized lesions, while topical medications are preferred for widespread or sensitive areas. Notably, improper treatment may lead to scarring or pigmentation changes, so selecting an appropriate method is critical. Additionally, educating patients about hygiene practices, such as avoiding sharing personal items and preventing scratching of lesions, can help prevent the spread of MC.