Lupus patients at higher risk of TB
Asian patients with systemic lupus erythematosus (SLE) are more likely to have tuberculosis (TB) than individuals without SLE, indicating SLE as a predictor of TB, a study shows.
“Patients with SLE should be considered as a high-risk group for TB, active screening for latent patients and treatment for positive TB patients is needed,” according to the researchers led by Dr Yang Yong from the Department of Epidemiology at Singapore General Hospital (SGH), Singapore.
Among the 301,568 patients in the hospital database studied, 841 patients (0.3 percent) had SLE and 1,843 patients (0.6 percent) had TB. Of the patients with SLE, 17 also had TB (2.0 percent). [Rheumatol Int 2017;37:1027-1033]
TB occurred at a significantly higher rate among patients with SLE than those without (2.0 percent vs 0.6 percent; p<0.001). Specifically, SLE was associated with a higher rate of pulmonary TB (p<0.001) but not extrapulmonary TB (p=0.06).
Patients with had an almost fivefold risk of having TB than those without SLE (adjusted odds ratio, 4.6; p<0.001), after adjusting for age, gender, ethnicity, nutritional deficiency, comorbidities, organ transplantation, and admission class.
According to the researchers, the risk of developing TB doubles to 10 folds if patients with SLE also had comorbidities such as diabetes and hypertension.
“Patients with lupus face the possibility of irreversible damage to vital organs like the kidney, lungs, heart, joints and other organs. These can weigh heavily on their minds. And now, they also have to worry about getting TB that can be fatal if not treated,” said study co-author Professor Julian Thumboo, a senior consultant at the Department of Rheumatology and Immunology, SGH.
Suggesting on possible underlying mechanism mediating the association between SLE and TB risk, the researchers believed that patients with SLE have altered immunological responses which predispose them to infections, and that the use of corticosteroids in SLE treatment may also increase the risk of TB. [Infect Dis Clin North Am 2006;20:849-875; Lancet 2011;378:57-72]
“We hope the finding will prompt doctors and patients themselves to be watchful of unexplained chronic cough, weight loss or fever, and consider active screening if needed,” said Thumboo.