Atopic dermatitis, impaired cellular immunity, and molluscum contagiosum.

A substantial elevation in the level of serum IgE (7,000 to 19,000 ng/ml) was noted in a man with atopic dermatitis and chronic molluscum contagiosum. Cell-mediated immunity (CMI) was depressed in vivo (cutaneous anergy), whereas in vitro tests showed normal numbers of "T" rosette-forming lymphocytes, a normal phytohemagglutinin-P-elicited lymphocyte transformation response, and lymphocyte transformation reactivity to the antigens streptokinase-streptodornase and purified protein derivative. Accumulated evidence suggests that patients with atopic dermatitis may have, associated with an elevated serum IgE level, a functional defect(s) in CMI that is greater in vivo than in vitro. This functional defect may impair host defense and account for the chronic molluscum contagiosum infection present in this patient.