Since TNF- inhibitors have been used in Korea, a few cases of TNF- inhibitor associated tuberculosis have been described. and inflammatory disorders including rheumatoid arthritis (RA), ankylosing spondylitis and Crohn’s disease [4]. Occasionally, these agents have been associated with infectious complications [5,6]. TNF- inhibitors have been suggested to increase the risk of tuberculosis; this is not surprising considering the role of TNF- in the defense mechanisms against mycobacterium [7]. Therefore, physicians must be vigilant in the prevention and early detection of tuberculosis, in patients that receive TNF- inhibitors, particularly with unusual manifestations of the disease. Although several complications have been described following treatment with TNF- inhibitors, tuberculous arthritis has not been reported previously in Korea [8]. We describe a 57-year-old woman who developed severe tuberculous arthritis in the elbow joint following etanercept administration for RA. == CASE REPORT == A 57-year-old woman was admitted to the hospital because of swelling, pain and warmth noted at the right elbow. The patient had seropositive RA diagnosed 15 years ago. The involved joints included wrist, elbow, knee, and ankle, bilaterally. She underwent bilateral knee arthroplasty 9 years previously and right ankle arthrodesis 2 years ago. Recently, GS-9973 (Entospletinib) the patient was treated with naproxen, prednisolone, methotrexate and cyclosporine A. Despite treatment, the symptoms remained active. Three months prior to admission she was started on etanercept injections (25 mg, twice weekly) combined with methotrexate, prednisolone and aceclofenac. A purified protein derivative (PPD) skin test performed before administration of etanercept was negative with 3 mm induration and a chest X-ray revealed no evidence of tuberculosis. The patient did not have a history of tuberculosis nor any known exposure to persons with active tuberculosis. The articular symptoms improved gradually after the etanercept injections. The serial laboratory tests showed improvement during the use of etanercept (Table 1). However, one month before admission, the patient began to experience swelling and pain of the right elbow joint. Intermittent fever and anorexia were also reported to be present. Her temperature was 38, blood pressure 130/80 mmHg, and pulse 80/minites. Physical examination revealed swelling with moderate tenderness and local heat around the right elbow. The range of motion was very limited. There was no lymphadenopathy. Chest and abdominal examinations were normal. Laboratory evaluation showed an increase in acute phase reactants. Renal and liver function tests were normal (Table 1). Blood and urine cultures were negative. The aspirates from the elbow joint showed cloudy yellow fluid with a white blood cell 75,000/mm3(95% of neutrophil). Gram staining of the synovial fluid revealed no bacteria. A chest radiograph demonstrated no new infiltrates. Plain radiography of GS-9973 (Entospletinib) the elbow joint disclosed extensive osteolytic bony destruction (Fig. 1). Arthroscopic debridement and synovectomy were performed. Severe inflammatory changes in the synovium with destruction of cartilage and subchondral bone were noted (Fig. 2). Pathology examination Rabbit Polyclonal to FA7 (L chain, Cleaved-Arg212) of the biopsy specimen revealed numerous granulomas composed of epithelioid cells and giant cells (Fig. 3). Eventually, cultures of the joint tissue specimen and joint fluid grewMycobacterium tuberculosis. The patient was treated with rifampin, isoniazid, pyrazinamide and ethambutol. The treatment with etanercept was discontinued. Three weeks later, there was significant decrease in the swelling and tenderness over the joint. The elbow discomfort continues to improve. == Table 1. == Laboratory tests before and during the use of etanercept Figures in parenthesis refer to reference values. WBC, white blood cells; ESR, erythrocyte sedimentation rate; CRP, C-reactive protein; AST, aspartate aminotransferase; ALT, alanine aminotransferase. == Figure 1. == Plain radiography of the right elbow. Extensive osteolytic bony lesions is shown. == Figure 2. == Arthroscopic view of the elbow joint. Severe inflammatory changes in hypertrophic synovium is observed. == Figure 3. == Histologic examination of synovial tissue. Chronic inflammation with granuloma composed GS-9973 (Entospletinib) of epithelioid cells and giant cells is shown (H&E, 200). == DISCUSSION == TNF- stimulates the production of proinflammatory cytokines and influences the maturation of inflammatory cells [5]. It promotes recruitment of inflammatory cells to the area of infection, and stimulates the formation and maintenance of a granuloma. In addition, TNF- directly activates macrophages, which engulf and kill the mycobacterium and other pathogens. Thus, it is.