Molluscum contagiosum is a contagious skin disease caused by the molluscum contagiosum virus. It is characterized by the appearance of single or multiple waxy papules on the skin with an umbilicus at the top, from which cheesy molluscum bodies can be squeezed out.
Etiology and pathogenesis
This disease is caused by the molluscum contagiosum virus, a DNA virus belonging to the Poxviridae family. Measuring approximately 300μm × 200μm × 100μm, it is one of the largest pathogenic viruses in humans. Electron microscopy shows that viral formation is closely related to the cytoplasm. The cytoplasmic matrix condenses and eosinophilic granules appear, aggregating into large particles, called granular composite viruses (initial type); subsequently, fine granular viruses (intermediate type) are formed; finally, a masonry-like outer shell and a dumbbell-shaped DNA core are formed, and the entire cytoplasmic matrix becomes a viral inclusion body, also known as a molluscum body. The characteristic skin lesions produced by molluscum contagiosum virus are easily diagnosed clinically, but their appearance on the genitals can be confusing, in which case a pathological diagnosis can be made. This disease can be transmitted through direct contact, autoinoculation, or sexual contact. In patients with AIDS, leukemia, or those using glucocorticoids or immunosuppressants, the rash can be widespread.
Clinical features
It is most common in children and young adults. It initially appears as millet-sized papules, gradually enlarging to the size of a mung bean, hemispherical in shape, with a central umbilicus, and a waxy, skin-colored surface. A white, cheesy substance, called a molluscum body, can be squeezed from the center. The number of lesions varies and they do not merge. In women, molluscum contagiosum on the vulva is often located on the mons pubis, labia majora and minora, and perianal area. Lesions can be single or multiple. When multiple lesions are present, they may be arranged in a linear pattern.
Histopathological features
The lesions are mainly in the epidermis. The epidermis proliferates extensively and extends into the dermis, and is divided into multiple pear-shaped lobules. Numerous eosinophilic molluscum bodies can be seen within the proliferating epidermal cells.
Differential diagnosis
This disease is easily diagnosed based on its clinical features. For atypical clinical features or single skin lesions, histopathological examination may be performed to confirm the diagnosis.
treat
The molluscum contagiosum body can be ruptured with sterilized tweezers, the contents squeezed out, and then 2.5% iodine tincture applied. Studies have shown that topical application of 5% imiquimod ointment can treat molluscum contagiosum. Before the lesions subside, avoid close contact with others (such as sexual activity), and try to avoid using shared towels and bath towels. Avoid vigorous scratching to prevent self-inoculation.
The above content is exclusively authorized for use only and may not be reproduced without the copyright holder's authorization.
