Quantiferon-TB Gold in tube assay for the screening of tuberculosis before and during treatment with tumor necrosis factor alpha antagonists.

INTRODUCTION: The usefulness of interferon-gamma (IFN-γ) release assays for tuberculosis screening before tumor necrosis factor-alpha (TNF-α) antagonists and for monitoring during treatment is a contraversial issue. The aims of this study were to determine whether TNF-α antagonists affect the results of the Quantiferon-TB Gold in-tube assay (QTF); to assess how QTF performs in comparison with the tuberculin skin test (TST) in rheumatoid arthritis (RA) patients who are about to start treatment with TNF-α antagonists, RA patients who are not candidates for treatment with TNF-α antagonists, rheumatology patients with confirmed current or past tuberculosis infection, and healthy controls, and to determine the specificity of the QTF test to differentiate leprosy patients, another group of patients infected with mycobacteria. METHODS: The 38 RA patients who were prescribed TNF-α antagonists, 40 RA patients who were not considered for TNF-α antagonist use, 30 rheumatology patients with a history or new diagnosis of tuberculosis, 23 leprosy patients, and 41 healthy controls were studied. QTF and TST were done on the same day, and both were repeated after a mean of 3.6 ± 0.2 months in patients who used TNF-α antagonists. RESULTS: Treatment with TNF-α antagonists did not cause a significant change in the QTF or TST positivity rate (34% versus 42%; P = 0.64; and 24% versus 37%; P = 0.22). Patients with leprosy had a trend for a higher mean IFN-γ level (7.3 ± 8.0) and QTF positivity (61%) than did the other groups; however, the difference was not significant (P = 0.09 and P = 0.43). CONCLUSIONS: Treatment with TNF-α antagonists does not seem to affect the QTF test to an appreciable degree. The higher IFN-γ levels in leprosy patients deserves further attention.

Successful management of cryoglobulinemia-induced leukocytoclastic vasculitis with thalidomide in a patient with multiple myeloma.

Leukocytoclastic vasculitis (LV) is a systemic inflammatory disorder involving mostly the small vessels. It is characterised by segmental angiocentric neutrophilic inflammation, endothelial cell damage and fibrinoid necrosis. LV is related to a variety of clinical disorders including cryoglobulinemia and, very rarely, multiple myeloma (MM), among many others. The development of LV in patients with MM has been linked to cryoglobulinemia, infections, drugs and paraneoplasia. It has been speculated that myeloma patients with a poorer prognosis and progressive disease are more prone to develop LV. Thalidomide is a rediscovered old drug with anti-angiogenic, immunomodulatory and anti-inflammatory properties. It is highly effective in the treatment of MM and other clinical disorders such as leprosy, various cancers, graft-versus-host disease and autoimmune diseases. We report here a female patient with Durie-Salmon stage IIA MM who initially presented with cryoglobulinemia and LV. LV in this patient was primarily considered to be the result of progressive cryoglobulinemia, which was closely associated with MM. She was successfully managed with thalidomide and dexamethasone.