POS0949 CLINICAL FACTORS ASSOCIATED WITH PNEUMOCYSTIS PNEUMONIA DESPITE ITS PRIMARY PROPHYLAXIS: A CASE-CONTROL STUDY

Background Previous studies have suggested that primary prophylaxis against pneumocystis pneumonia (PCP) using trimethoprim-sulfamethoxazole (TMP-SMX) is beneficial in patients with rheumatologic diseases receiving immunosuppressive drugs [1] . However, there little evidence for an optimal duration or a time point of withdrawal. Objectives This study aims to investigate the risk factors are associated PCP occurrence despite its prophylaxis, and, ultimately, provide regarding ideal schedule prophylaxis. Methods case-control included treatment episodes rheumatic who received prophylactic TMP-SMX between 2010 and 2022 tertiary referral center South Korea. The index date was defined as starting dose TMP-SMX. We captured cases occurred within 1 year from based on review medical record by two independent expert investigators. effect clinical factors, such demographics, underlying disease, treatment, pattern examined binary logistic regression. Results A total 1,379 were analyzed, eleven during observation—a one-year incidence 0.80 (95% CI=0.40-1.43) per 100 person-years. In 10 (90.9%), after discontinuation mean (SD) interval 185.6 (90.9) days. group 108.5 (132.3) main reasons withdrawal adverse events (5 cases) treating physicians’ decisions cases). glucocorticoid at cessation most critical factor PCP. Patients more than 15 mg/day prednisone equivalent showed significantly higher odds developing (OR=15.06; 95% CI=1.92-117.94). presence structural lung disease not result consistent multivariable analysis adjusted age, rituximab azotemia, lymphopenia (adjusted OR=12.21; CI=1.52-98.24) (Table 1). Conclusion Discontinuation greater mg increases PCP, which suggests when glucocorticoids tapered less 15mg/day dosage may be reasonable consider withdrawing Reference [1]Park JW, Curtis JR, Moon J, Song YW, Kim S, Lee EB. Prophylactic exposed prolonged high-dose glucocorticoids. Ann Rheum Dis. 2018;77(5):644-9. Table 1. Factors Univariable Multivariable OR CI) P Age 1.06 (1.01-1.11 ) 0.02 1.05 (0.10-1.10) 0.08 Sex, female 0.71 (0.22-2.35) 0.58 SLE 0.34 (0.04-2.64) 0.30 AAV 4.19 (1.27-13.84 0.50 (0.08-3.07) 0.46 Other vasculitis 0.65 (0.14-3.02) Inflammatory myopathies 0.55 (0.07-4.33) 0.57 Rheumatoid arthritis 3.01 (0.38-24.03) Others 3.81 (0.47-30.57) 0.21 Rituximab 6.03 (1.82-19.99 <0.01 4.06 (0.87-18.99) Cyclophosphamide 1.55 (0.41-5.87) 0.52 Mycophenolate mofetil 0.99 (0.13-7.76) Azathioprine 1.00 (0.13-7.90) Prophylaxis 0.10 (0.99-1.00) 0.16 Last Gc ≤ 15.06 (1.92-117.94 0.01 12.21 (1.52-98.24 Azotemia 9.88 (2.13-45.94) 0.00 7.04 (1.31-37.71 Lymphopenia 5.18 (1.51-17.81) 3.13 (0.86-11.39) Structural 2.34 (0.71-7.70) * Adjusted relevant association (P < 0.1) univariable AAV, ANCA vasculitis; Gc, glucocorticoid; SLE, systemic lupus erythematosus Acknowledgements: NIL. Disclosure Interests None Declared.