H de 46 ans. Lsions nodulaires du pubis et
Deux lsions sont examines, l'une se prsentant
sur coupe comme un nodule
enchass dans le derme, et l'autre comportant un pertuis
abouch l'piderme. Les deux structures sont formes
par un revtement pidermique
hyperplasique, avec maturation vers une couche granuleuse
paisse, donnant une couche corne anormale, toutes deux constitues
de cellules prsentant un effet cytopathique virale par surcharge
virales cytoplasmiques, osinophiles.
Molluscum contagiosum (Akerman's
Molluscum contagiosum is a skin disease characterized by small,
firm, usually multiple nodules that, when fully developed, have
central cores from which white keratinous material can be expressed.
microscopic picture is characteristic. The dermis is indented by
a sharply delimited and lobulated
mass of proliferating epithelium. As the cells differentiate within
the mass, their cytoplasm gradually is filled by a faintly granular
eosinophilic inclusion that displaces the nucleus and enlarges the
cells. These molluscum bodies are formed of viral particles that
are similar in size and mode of formation to the poxviruses. Inflammation
in the surrounding dermis is intense, sometimes to the point of
simulating a leukemic process. Metaplastic ossification has been
Reed and Parkinson studied the histogenesis of molluscum contagiosum
and concluded that the lesion ariseson the basis of follicular neogenesis.
They found areas of hair bulb differentiation at the periphery,
occasionally associated with areas of sebaceous gland differentiation.
However, the disease can also appear in places where there are no
hair follicles, such as the palms, indicating that the epidermis
itself may be affected.