RESUMO
Background: Vitiligo is a multifactorial, polygenic, autoimmune skin disorder caused by selective destruction of melanocytes. Interleukin 1 receptor antagonist intron 2 polymorphism was found to be associated with various autoimmune disorders. Aims: We aimed to investigate the association of interleukin 1 receptor antagonist intron 2 variable number of tandem repeats polymorphism (rs2234663) with vitiligo to assess interleukin 1 receptor antagonist transcript levels and to perform possible genotype–phenotype correlation. Methods: Three hundred and seven vitiligo patients and 316 controls were enrolled in the study, genotyping of interleukin 1 receptor antagonist rs2234663 was performed by polymerase chain reaction, and relative gene expression of interleukin 1 receptor antagonist was carried out in peripheral blood mononuclear cells from patients (n = 36) and controls (n = 36) by real-time-PCR. Results: A significant difference was observed in the frequency of interleukin 1 receptor antagonist *A (1/2) genotype among patients with active and stable vitiligo (P = 0.0172). Interleukin 1 receptor antagonist*A (2/2) genotype and allele frequencies were significantly different between SV patients and controls (P = 0.0246 and P = 0.0046, respectively). Significant difference was also observed for interleukin 1 receptor antagonist*A2 (allele) in active and stable vitiligo patients (P = 0.0060). However, other comparisons did not show any significant difference in genotype and allele frequencies. Moreover, interleukin 1 receptor antagonist*A (3/2) genotype was observed only in patients whereas interleukin 1 receptor antagonist*A (5/2) was observed only in controls. Gene expression analysis showed no significant difference in interleukin 1 receptor antagonist transcript levels in patients compared to controls (P = 0.5962). Interestingly, genotype–phenotype correlation analysis revealed that individuals with IL1RN*A (2/2) exhibited higher interleukin 1 receptor antagonist expression compared to other major genotypes interleukin 1 receptor antagonist*A (1/2) (P = 0.01) and interleukin 1 receptor antagonist*A (1/1) (P = 0.03). Limitations: More case-control studies on interleukin 1 receptor antagonist rs2234663 polymorphism and gene expression from different ethnic populations are required to explore the impact of interleukin 1 receptor antagonist in vitiligo susceptibility. Conclusion: Interleukin 1 receptor antagonist*A2 might be a risk factor for progressive vitiligo.
RESUMO
It is interesting to study an autoimmune condition like dermatomyositis (DM) in the setting of immunosuppression due to human immunodeficiency virus (HIV) infection. An HIV seropositive female aged 30 years, presented with a nonitchy rash over the face, breathlessness, diarrhoea and difficulty in raising her hands above her head. A heliotrope rash around the eyes, Gottron's papules and proximal muscle weakness were found to be present. C reactive protein, erythrocyte sedimentation rate and lactate dehydrogenase levels were raised, but creatinine phosphokinase and anti-nuclear antibody profile were normal. Her HIV serostatus was confirmed by Western blotting, keeping in mind the potential for false positive HIV serology in an autoimmune disorder. Her CD4 count was 379 cells/mm3. An X-ray of the chest showed bilateral pleural effusion with raised pleural fluid adenosine deaminase levels. Clinical findings and laboratory investigations favored the diagnosis of DM and HIV infection with tuberculous effusion in an HIV seropositive patient. She was treated with antibiotics, four-drug anti-tubercular treatment, systemic steroids and later, antiretroviral treatment. Chances of a false positive antibody test for HIV should be considered in a patient having an autoimmune disease such as DM.