Association of geographic tongue and fissured tongue with ABO blood group among adult psoriasis patients – A novel study from a tertiary care hospital in Saudi Arabia

Abstract Objective We aimed to determine if there was any association between geographic tongue and fissured tongue with ABO blood group among adult psoriasis patients in Saudi Arabia. Materials and method This hospital-based cross-sectional study included 100 consecutive new adult patients diagnosed with psoriasis and 100 case-matched participants in the control group (non-psoriatic). Socio-demographic and dermatologic parameters, intraoral lesions (geographic tongue (GT) and fissured tongue (FT)) along with ABO blood grouping and immunoglobulins (Ig)) were recorded which was evaluated using the Chi-square test or Fisher's exact test. Results 74% of patients had an early age of onset, and 48% of them reported this disease in their parents.76% in generalized psoriasis had plaque type while 78% in the localized type had pustular type lesions. 70% of psoriatic patients had O positive blood group. 63% of tongue lesions seen in these patients were GT, and it was most prominent in O positive (64.28%) and O negative (62.50%) blood groups. GT was prevalent among in females (75.6%). Conclusion This study demonstrates a positive association of both GT and FT in this population of adult patients with psoriasis compared to a case-matched control population without psoriasis.