Background and Aim: Pemphigus vulgaris (PV) is an autoimmune blistering disease which is specific for skin and mucosal membranes. Its association with connective tissue diseases has already been reported. Considering this association, presence of Anti Nuclear Antibodies (ANAs) in PV patients will not be surprising. The aim of this study was to compare the frequency of ANA positive cases in patients suffering PV with a control group.
Methods: In this case-control study, the cases were selected from the patients with PV whom were hospitalized at Razi Hospital, Tehran. The controls were chosen from patients who did not have PV. The data were collected using a questionnaire, which was designed for gathering information on participants' age, sex, PV phenotypes, and the result of ANA test. ANA positivity was assessed using indirect immunofluorescence, HEP2.
Results: In 8 (26.7%) of 30 PV patients and 3 (10.0%) of 30 controls ANA was positive (P=0.095). The most common ANA positive patterns among cases and controls were homogeneous and speckled patterns, respectively (P=0.26).
Conclusion: Although in this study the frequency of positive ANA result among controls was similar to what were reported in previous studies, the frequency of this finding among PV patients was different from the previous reports. Differences in the sensitivity of the laboratory kits used in different studies as well as in the threshold for ANA positivity, and differences in the patients' eligibility criteria in different studies may explain the observed discrepancies. Clinical follow up of the PV and requesting an ANA test in the case of appearance of the signs of connective tissue diseases is recommended.