Systemic Immune Inflammatory Index Is Associated with Pustular Psoriasis: A Single Center Retrospective Study

Abstract

Introduction: Psoriasis is a chronic multi-systemic inflammatory skin disease that presents with erythema, thickness, and scaling of the skin. Genetic and environmental factors are associated with its etiology. Recently systemic immune inflammatory index, has been proposed as a biomarker for prognosis and severity prediction. Although it has been studied in psoriasis in general, no study exists for its association with the individual types of psoriasis. This study thus aimed to determine its association with clinical characteristics of psoriasis subtypes. Materials and Methods: Data were retrospectively retrieved from the hospital electronic medical database from January 2020 to August 2022. Only patients with CBC results were included. Clinical data retrieved were: Patients’ age, gender, type of psoriasis diagnosed, body mass index, duration of the disease, family history of psoriasis, history of smoking, diabetes, and hypertension records. Laboratory data retrieved were: Complete blood count (CBC), C-reactive protein, Immunoglobulin E (IgE), Total cholesterol, Triglycerides and Low-density lipoprotein cholesterol. Data were analyzed in SPSS and GraphPad prism. Results: The study enrolled 85 patients with psoriasis; 56.47% males, and 43.53% females. 7.6% had psoriasis for less than 10 years, while 42.4% had the disease for more than 10 years. Psoriasis vulgaris was the most common diagnosis, 41.2%, followed by p. pustular, 30.6% and then p. erythroderma 28.2%. Mean age ± SD of the p. vulgaris, p. pustular and p. erythroderma patients were 47.3 ± 15.3; 45.3 ± 14.6, and 57.1 ± 11.7 respectively. SII was significantly higher in p. pustular than the rest, (p < 0.0001). SII was significantly associated with hypertension p. pustular patients. C-reactive protein was significantly upregulated in both psoriasis pustular and erythroderma but not vulgaris (all p < 0.001), while leukocytosis was observed in psoriasis pustular. Conclusion: In summary, systemic immune inflammatory index (SII) was significantly higher in psoriasis pustular than other subtypes of psoriasis, and had an association with hypertension in psoriasis pustular patients. These findings suggest a possible association between SII and psoriasis pustular that should be investigated in an independent study.