Abstract
CONTEXT: In vivo epidermal nuclear staining (ENS) can be found in patients with autoimmune connective tissue diseases (CNTDs) and other diseases. AIMS: The aim of this study was to reveal the underlying diseases and direct immunofluorescence (DIF) characters of patients with in vivo ENS and association of in vivo ENS with circulating autoantibodies. SETTINGS AND DESIGN: A retrospective analysis was conducted involving skin biopsy specimens submitted for DIF study at the Dermatoimmunology Laboratory at Siriraj Hospital between 2002 and 2012. SUBJECTS AND METHODS: The findings of DIF study, clinical manifestations, and diagnosis of patients who had positive ENS were investigated. STATISTICAL ANALYSIS USED: The SPSS software version 18.0. Descriptive statistics were used to report demographic data, clinical characteristics, and laboratory investigation results. Moreover, Chi-squared test or Fisher's exact test were used to compare the categorical variables. RESULTS: One hundred and thirty-eight out of 3735 submitted specimens (3.7%) showed positive ENS. The most common diagnosis was CNTD (79%) followed by vasculitis (10.1%). Lupus erythematosus was the most common diagnosis among CNTD (78%). No association between levels of serum antinuclear antibodies (ANA) titer and intensity of ENS (P = 0.660). However, we found that patients with positive in vivo ANA had lower prevalence of systemic involvement. CONCLUSIONS: Although lupus erythematosus was the most common diagnosis among patients with in vivo ENS, the presence of ENS does not indicate any specific diagnosis. However, patients with ENS tend to have less systemic involvement.