[Tuberculosis in a cohort of patients with systemic lupus erythematosus]

1) To study tuberculosis (TB) infection in a cohort of patients with systemic lupus erythematosus (SLE) and to compare its frequency and characteristics with that of others series. 2) To look for differential characteristic among SLE patients with and without TB. 3) To investigate if there was any relationship between TB's most severe forms and higher doses of glucocorticoids (GC) or other immunosuppressants.

Retrospective review of medical records of 789 SLE patients and description of the clinical characteristics of 13 cases of active TB infection among them. Bibliographical search in MEDLINE-PubMed of the SLE/TB series published, using the terms: infection, tuberculosis, systemic lupus erythematosus. Comparative study of clinical, biological and therapeutic differences between cases (SLE/TB+) and controls (SLE/TB) using χ(2) and Fisher exact test.

Thirteen patients with active tuberculosis were detected (10 women, average age 36 years/SD 11,2/prevalence 1,6%). Nine (69,2%) of them were primary infections and 4 (30,8%) reactivations. Microbiological diagnosis (smear examination for acid-fast bacilli and/or culture on Lowestein-Jensen medium) was established in 11 patients (84,6%). TB Pulmonary manifestations was present in 9 patients (69,2%) and extra-pulmonary manifestations were found in 8 [(61,5%); 6 of them (46%) were disseminated forms]. Nine (69,2%) patients were on GC therapy at the moment TB was diagnosed. Four of the TB patients died (30,8%). Myositis was more frequent in TB cases (p < 0,05). This data is similar to that reported in the literature.

In our series, TB mortality was high (30,8%) in a patients with SLE. Frequency of extrapulmonary forms was double than that described in the Spanish population. Patients with higher GC dose had more severe forms of TB.