Characteristics and diseases associations of tuberculosis in lupus: A retrospective single-center analysis

Abstract

Objective: The objective of this study is to identify factors associated with active tuberculosis (TB) in patients with systemic lupus erythematosus (SLE) and to study the impact of TB on SLE disease activity. Methodology: We screened case records of 643 individuals with SLE for the diagnosis of TB. SLE patients with TB (cases) (n = 29) were matched for age, sex, and disease duration in the ratio of 1:3 with controls (n = 94) (SLE without TB). Results: Pulmonary TB was seen in 41% (n = 12) and extrapulmonary TB in 59% (n = 17). Musculoskeletal TB (n = 6; 34.2%) was the most common extrapulmonary manifestation. TB was seen among those with lupus nephritis (55% vs. 38.4%) (P < 0.005) and those with autoimmune hemolytic anemia (48% vs. 38%). A higher median dose of daily glucocorticoids 11.5 (7.5–30) in 1 month preceding TB diagnosis was associated with a higher incidence of TB. Upon multivariable analysis, 1 month mean daily dose of glucocorticoids ≥ 7.5 mg (odds ratio [OR], 1.47; 95% confidence interval [CI], 1.07–2) was independently associated with TB. On a follow-up duration of 16 months, SLE flare was more among those with TB as compared to the controls (OR-2.49 95%; CI-1.39–4.48; P = 0.002). Conclusion: Extrapulmonary TB is the most common form in individuals with SLE. A higher steroid dose seems to predispose to TB infection. TB infection may increase the risk of SLE disease flare.

Keywords

• immunosuppressives
• infection
• latent tuberculosis
• lupus nephritis
• mycobacterium
• systemic lupus erythematosus