Risk factors for invasive fungal infections in patients with connective tissue disease: Systematic review and meta-analysis

Objective: Invasive fungal infections (IFIs) are life-threatening opportunistic infections in patients with connective tissue disease CTD) that cause significant morbidity and mortality. We attempted to determine the potential risk factors associated with IFIs in CTD. Methods: We systematically searched PubMed, Embase, and the Cochrane Library databases for relevant articles published from the database inception to February 1, 2023. Results: Twenty-six studies were included in this systematic review and meta-analysis. Risk factors identified for IFIs were diabetes (odds ratio [OR], 1.62; 95% confidence interval [CI], 1.00 to 2.64), pulmonary diseases (OR 3.43; 95% CI 2.49 to 4.73), interstitial lung disease (ILD; OR, 4.06; 95% CI, 2.22 to 7.41), renal disease (OR, 4.41; 95% CI, 1.84 to 10.59), glucocorticoid (GC) use (OR, 4.15; 95% CI, 2.74 to 6.28), especially moderate to highdose GC, azathioprine (AZA) use (OR, 1.50; 95% CI, 1.12 to 2.01), calcineurin inhibitor (CNI) use (OR, 2.49; 95% CI, 1.59 to 3.91), mycophenolate mofetil (MMF) use (OR, 2.83; 95% CI, 1.59 to 5.03), cyclophosphamide (CYC) use (OR, 3.35; 95% CI, 2.47 to 4.54), biologics use (OR, 3.43; 95% CI, 2.36 to 4.98), and lymphopenia (OR, 4.26; 95% CI, 2.08 to 8.73). Hydroxychloroquine (HCQ) use reduced risk of IFIs (OR, 0.67; 95% CI, 0.54 to 0.84). Furthermore, 17 of the 26 studies only reported risk factors for Pneumocystis jiroveci pneumonia (PJP) in patients with CTD. Pulmonary disease; ILD; and the use of GC, CNIs, CYC, methotrexate (MTX), MMF and biologics, and lymphopenia increased the risk of PJP, whereas the use of HCQ reduced its risk. Conclusion: Diabetes, pulmonary disease, ILD, renal disease, use of GC (especially at moderate to high dose) and immunosuppressive drugs, and lymphopenia were found to be associated with significant risk for IFIs (especially PJP) in patients with CTD. Furthermore, the use of HCQ may reduce the risk of IFIs in patients with CTD.