Association of tibial osteomyelitis and pneumonitis due to miliary tuberculosis in a patient with systemic lupus erythematosus.

Systemic lupus erythematosus (SLE) is a multisystem autoimmune disease, which has great prevalence and uncommon manifestations of opportunistic infectious diseases, mainly due to the multiple abnormalities of the immune system and the immunosuppressive effect of the medications used in its treatment. Patients whit SLE have an increased incidence of tuberculosis, and osteoarticular involvement occurs in 1%-3% of the cases, manifesting as pain, reduction in mobility, and increased osteoarticular volume. The radiographic findings are often nonspecific. Magnetic resonance imaging (MRI) is an useful test to define the severity of bone involvement; however, the etiological diagnosis can only be established by use of synovial fluid or bone cultures or the histological study of the affected areas. Due to the lack of specificity of the findings, there is usually a mean diagnosis delay of 11 months. We report the case of a female patient with SLE and predisposing factors for tuberculosis infection/reactivation. The MRI was important to define bone involvement, and the etiological diagnosis was established by use of bone biopsy. The patient also had lung involvement due to miliary tuberculosis, shown on plain chest radiography and CT scan and confirmed on culture of Mycobacterium tuberculosis in the sputum. There was a 1.5-month delay in beginning therapy, which is considered a short time when compared to the reports in the literature. In conclusion, bone tuberculosis, although rare, should always be remembered as a differential diagnosis of patients with SLE and osteomyelitis, mainly those with history of pulmonary tuberculosis.