Varicella-zoster virus immunity in dermatological patients on systemic immunosuppressant treatment

• Published in: British journal of dermatology (1951) Vol. 164; no. 6; pp. 1387 - 1389
• Main Authors: Hackett, C.B., Wall, D., FitzGerald, S.F., Rogers, S., Kirby, B.
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Publishing Ltd 01-06-2011; Wiley-Blackwell
• Subjects: Adolescent; Adult; Aged; Aged, 80 and over; Antibodies, Viral - blood; Biological and medical sciences; Chickenpox - immunology; Dermatology; Female; Herpesvirus 3, Human - immunology; Humans; Immunity, Active - immunology; Immunoglobulin G - blood; Immunosuppressive Agents - therapeutic use; Male; Medical sciences; Middle Aged; Skin Diseases - drug therapy; Skin Diseases - immunology; Young Adult; Virus; Human; Varicella zoster virus; Treatment; Dermatology; Herpesviridae; Alphaherpesvirinae; Disseminated; Immunosuppressive agent; Immunity
• ISSN: 0007-0963; 1365-2133
• DOI: 10.1111/j.1365-2133.2011.10315.x

Summary
Background  Primary varicella infection is caused by varicella‐zoster virus (VZV). It is a common childhood infection, which is usually benign but can occasionally cause morbidity and mortality. In immunosuppressed adults, atypical presentation and disseminated disease can occur with significant morbidity and mortality. A VZV vaccine is available.
Objectives  This study was designed to measure the prevalence of immunity to VZV and to determine the predictive value of a self‐reported history of varicella infection in a population of dermatological patients receiving systemic immunosuppressant therapy. We sought to assess the need for routine serological testing for varicella‐zoster immunity in this cohort.
Methods  Serological testing for VZV immunity was done on 228 patients receiving systemic immunosuppressive treatment for a dermatological condition. Information regarding a history of previous primary VZV infection was obtained from each patient.
Results  Two hundred and twenty‐eight patients had VZV serology performed. The mean age of the patients was 49·6 years. The prevalence of VZV seropositivity in this cohort was 98·7%. One hundred and two patients (44·7%) reported having a definite history of primary VZV. The sensitivity of a self‐reported history of VZV infection was 45·3% with a specificity of 100%. The positive and negative predictive values of a self‐reported history of VZV for serologically confirmed immunity were 100% and 2·3%, respectively.
Conclusions  The prevalence of VZV IgG antibodies in our cohort of Irish dermatology patients receiving immunosuppressive therapy is 98·7%. A recalled history of varicella infection is a good predictor of serological immunity. This study has shown that there are VZV‐susceptible individuals within our cohort. These patients did not have a clear history of previous infection. We recommend serological testing of patients without a clear history of infection prior to the commencement of immunosuppressive therapy and vaccination of patients with negative serology.