EF is characterized histologically by eosinophilic follicular inflammation. There are several variants:
- Immunosuppression-associated EF (discussed herein)
- Ofuji disease
- Eosinophilic pustular dermatosis of infancy
Clinically, the disorder is characterized by recurrent, usually intensely pruritic papules and pustules in areas often affected by acne vulgaris. Occasionally, a more widespread distribution is seen. EF can be extremely symptomatic and refractory to treatment, but it may spontaneously improve as CD4 counts rise secondary to antiretroviral therapy for HIV. It can also worsen or manifest as part of an immune reconstitution phase.