Features and Associated Factors of Bacterial Skin Infections in Hospitalized Patients with Pemphigus: A Single-Center Retrospective Study

Abstract

Background: Infections were the primary cause of death (34.3%-55.5%) in patients with pemphigus. Skin was usually the origin of infections. The study aimed to explore features and associated factors of bacterial skin infections (BSIs) in inpatients with pemphigus. Methods: One hundred and eighty-four inpatients with pemphigus visiting the dermatology department of Peking University First hospital during 2013 to 2019 were continuously recruited to study the characteristics and associated factors of BSIs.Results: Of patients enrolled, pemphigus vulgaris (PV, n=142) and pemphigus foliaceus (PF, n=9) were most common, followed by pemphigus erythematosus (PE, n=25) and pemphigus vegetans (Pveg, n=1). Eighty-seven of 177 (49.2%) inpatients developed BSIs, and they had a longer length of stay compared with inpatients without BSIs (median: 18.9 days vs. 14.1 days, p = 0.008). Staphylococcus aureus was the most common bacteria and highly resistant to penicillin (91.9%). Higher levels of anti-Dsg1 autoantibodies (>124.2U/mL) (p<0.001, odds ratio [OR]=3.564, 95% confidence interval [CI]: 1.784-7.123) and anti-Dsg3 autoantibodies (>169.5U/mL) (p = 0.03, OR=1.074, 95% CI: 1.084-3.969) were underlying risk factors of BSIs. As for Gram’s stain of bacteria, females had a lower rate of Gram-positive infections (p = 0.03). Patients systematically using of antibiotics (p = 0.05) had a higher rate of Gram-negative infections. Inpatients with history of hospitalization had a higher rate of Gram-negative and co-infections (p = 0.03). Conclusions: Inpatients with pemphigus had a high incidence rate of BSIs. High levels of anti-Dsg1 (>124.2U/mL) and Dsg3 autoantibodies (>169.5U/mL) might be underlying risk factors for BSIs.