Epidermal nuclear staining: a distinct reaction pattern in connective tissue diseases.

Epidermal nuclear staining occurs as a result of anti-nuclear antibody (ANA) deposition in the nucleus of keratinocyte (‘In vivo ANA’). The frequency with which it occurs in various CTD’s varies between 2.6-9.8%.[2] The high prevalence in our study could be due to the smaller study sample. Four different patterns of ENS (viz. speckled, homogenous, nucleolar and rim) have been reported in the literature with speckled pattern being the commonest type. The patterns of ENS in the skin correlate with that of serum ANA in majority of cases.[3] The pattern of staining was not recorded in our study. Rodrigues et al found no association between this phenomenon and LBT.[4] Deposition of immunoglobulin does not cause any pathological changes per se, as it has been observed in both lesional skin and normal skin. In addition to skin, it has also been demonstrated in the renal and Figure 1: IgG epidermal nuclear staining (DIF, x200) Role of direct immunofluorescence (DIF) in the diagnosis of lupus erythematosus (LE) and other connective tissue diseases (CTD) is well-established. Deposition of various immunoreactants along the dermal-epidermal junction (DEJ) is highly characteristic of LE. However, DEJ is not the only site of immunopathological changes in connective tissue diseases. Immunoreactants may also be deposited in the epidermis (seen as epidermal nuclear staining or ENS) or in the papillary dermis.[1] Our objective was to study the prevalence of ENS in various connective tissue diseases and to find out if there was any association between ENS and serological abnormalities.