Pityriasis lichenoides chronica

Management Strategy

There are few therapeutic trials for this condition, and case series are only small. In many therapeutic trials PLC has been grouped together with pityriasis lichenoides et varioliformis acuta (PLEVA), and management strategies are therefore often similar or interchangeable.

Topical corticosteroids are generally reported as effective anecdotally in textbooks rather than in studies. They are often used with antihistamines to reduce pruritus, but they are not reported to affect the course of the disease.

The majority of reports describe benefits with ultraviolet ( UV) therapy , and therefore either UV alone or psoralen plus UVA (PUVA) therapy is recommended for all patients. The response appears to be unpredictable, however, and the total dose required is extremely variable.

Antibiotics appear to be more helpful in children, sometimes used in combination therapy.

For severe or refractory cases, methotrexate , acitretin combined with PUVA , and etanercept have all been described as effective in small numbers of patients.

For most treatment modalities, patients who have been described as improved have usually had fewer new lesions developing, a shortened disease course, and a greater time to relapse than untreated patients.

Although a skin biopsy is usually unnecessary in clinically obvious cases, it may be useful before commencing systemic therapy with more potential adverse effects.

An infective etiology is often suggested, but no pathogen has yet been implicated, though associations with toxoplasmosis, human herpesvirus-8 (HHV-8), and parvovirus B19 have been described. These reports tend to come from endemic areas, and so investigation for a triggering infection is unnecessary in cases without evidence of specific infection.