Association of Psoriasis with Autoimmune Disorders: Results of a Pilot Study

BACKGROUND: Association of psoriasis with other autoimmune diseases remains an ongoing research subject. OBJECTIVES: To investigate the association of psoriasis with other autoimmune disorders. MATERIALS AND METHODS: We studied 80 (M: F 57:23) psoriasis patients aged 13–75 years for concurrent autoimmune disorders. After clinical examination, hemogram, fasting blood sugar, HbA1c, thyroid function tests, anti-TPO antibody, rheumatoid factor, anti-tTG antibody, anti-CCP antibody, ANA, anti-dsDNA antibody, anti-Ro antibody, and fecal calprotectin were estimated. RESULTS: Mild-to-moderate and severe psoriasis was present in 86.3% and 13.8% patients, respectively. Psoriatic arthritis was present in 3.8% patients, all of whom also had severe psoriasis. Only 37 (46.3%) patients had clinical and/or sero-abnormality suggestive of autoimmune disorders; vitiligo in 3.8%, type-1 diabetes mellitus (DM) in 1.3%, and type-2 DM in 6.3% patients. Sero-positivity reflecting subclinical autoimmunity was noted for anti-CCP antibodies (in 2.5%), rheumatoid factor (in 2.5%), hypo- or hyper-thyroidism (in 8.8%), anti-TPO antibodies (in 5.0%), anti-tTG antibody (in 1.3%), ANA (in 5.0%), anti-dsDNA antibody (in 2.5%), and anti-Ro antibody in 11.3% patients. Elevated fecal calprotectin levels suggestive of inflammatory bowel disease (IBD) occurred in 11.2% of 27 patients. Multiple abnormalities happened in 2.5% patients. CONCLUSION: Apparently psoriasis patients seem to have a predilection for other autoimmune disorders particularly for vitiligo, diabetes mellitus, autoimmune thyroiditis, rheumatoid arthritis, and IBD. However, association between psoriasis and other autoimmune disorders at best remains tenuous for want of strong evidence. Nevertheless, screening for them will improve overall management of these patients. Cross-sectional study design and small number of study subjects remain important limitations.