The use of Mycobacterium tuberculosis HspX and GlcB proteins to identify latent tuberculosis in rheumatoid arthritis patients

Abstract

Rheumatoid arthritis (RA) is an autoimmune disease characterised by the destruction of articular cartilage and bone damage. The chronic treatment of RA patients causes a higher susceptibility to infectious diseases such as tuberculosis (TB); one-third of the world’s population is latently infected (LTBI) with Mycobacterium tuberculosis (Mtb). The tuberculin skin test is used to identify individuals LTBI, but many studies have shown that this test is not suitable for RA patients. The goal of this work was to test the specific cellular immune responses to the Mtb malate synthase (GlcB) and heat shock protein X (HspX) antigens of RA patients and to correlate those responses with LTBI status. The T-helper (Th)1, Th17 and Treg-specific immune responses to the GlcB and HspX Mtb antigens were analysed in RA patients candidates for tumour necrosis factor-α blocker treatment. Our results demonstrated that LTBI RA patients had Th1-specific immune responses to GlcB and HspX. Patients were followed up over two years and 14.3% developed active TB. After the development of active TB, RA patients had increased numbers of Th17 and Treg cells, similar to TB patients. These results demonstrate that a GlcB and HspX antigen assay can be used as a diagnostic test to identify LTBI RA patients.

Systemic Sclerosis and the Risk of Tuberculosis

“…These data were not significant, possibly because of the limited number of TB subjects (p = 0.064). Our results are similar to previous findings on patients with other autoimmune disorders, systemic lupus erythematous 39,40 , rheumatoid arthritis treated with biological agents 41,42 , and inflammatory myositis, all of which can lead to TB with greater extrapulmonary spread 43 . This is in part due to intrinsic immune dysregulation, permitting the TB bacilli to activate in organs where it is less often successful.…”

Development and validation of an advanced fragment analysis‐based assay for the detection of 22 pathogens in the cerebrospinal fluid of patients with meningitis and encephalitis

“…Recent reports have revealed the potential application of the detection of M. tuberculosis-specific antigens in CSF for the rapid diagnosis of TBM. 41,42 For serology assay of viruses, the most definitive diagnosis of virus infections is established by detecting CSF IgM antibodies or demonstrating at least a 4-fold increase in neutralizing antibody titers between the acute and convalescent phases. 43,44 CSF IgM is the most widely used test for HSV, CMV, and VZV.…”

Laboratory Diagnosis of Central Nervous System Infection

“…Recently several reports revealed potential application of detection of M. tuberculosis −specific antigens in CSF as rapid diagnosis of tuberculosis meningitis 39, 40 . The level of M. tuberculosis Early Secreted Antigenic Target 6 [ESAT-6] was associated with clinical severity, and may be used for the prognosis of tuberculosis meningitis 41, 42 .…”