A 31-year-old man, was admitted to the outpatient clinic with major complaints of reddish skin transformation, warmth, and swelling of the right knee that progressively occurred since 2013; there was also intermittent pain that has been experienced since the symptoms emerged. The pain characteristically was exacerbated after strenuous activities without respiratory manifestations were found. Losing appetite and weight for 3 kg in one month has been suffered, and no symptoms of night-sweats and chills are experienced. Contact history with TB patients was not found, but a traumatic injury occurred in September 2012. The patient had a motorcycle accident, injuring the same leg. The history of medication was analgesics and oral antibiotics, including cephalosporin. There were no allergic indications, including food and drugs. There was no history of malignancy or genetic abnormality in his family background.
In 2013, this patient was admitted to another hospital and had been diagnosed with acute infections with malignancy as a differential diagnosis. The patient was suggested to undergo further diagnostic examinations. However, he preferred to undergone alternative treatments such as massage and herbal medicines. The patient and his parents still thought that his condition was not dangerous to get surgery. After several years of these treatments, no improvement of symptoms and clinical conditions were reported. The swelling of the leg became more severe, with the increased frequency of pain exacerbated after 5 years of alternative medicine approach.
Physical examinations have reported the presence of swelling, reddish, and warm through palpation of the right knee with impaired proper motions. The affected extremity could not be flexed under 110  C, and extended -30  with no abnormality was found based on physical examinations of the spine, hip, and left knee. Meanwhile, chest radiograph demonstrated infiltration in both upper lobe lungs.
From the sequence radiograph examinations, it showed the progression of knee destruction. In 2013, there was only a narrowing of the joint gap (Fig. 1a). Still, after being ignored for 3 years, it has progressed to the bone destruction, which was indicated by the presence of a lytic lesion in both fibula and tibia (Fig. 1b).
Finally, another modality which has favorable of soft tissue infiltration, Magnetic Resonance Imaging (MRI) was used later. It showed the well-defined iso-hyperintense mass and free fluid collection that lead to right tuberculous knee arthritis with posterior abscess and synovitis infection (Fig. 2). Based on blood examination, no abnormality of complete blood count and thrombosis parameters were found. The patient was performed synovectomy in June 2018 by an orthopedist. Spinal anesthesia was performed before debridement and arthrotomy, followed by total synovectomy. The medial incision of the right patella revealed the synovial mass without any attachment to the adjacent structure (Fig. 3a). Later, histopathology revealed the epitheloid proliferation, granuloma, necrotic, lymphocyte infiltration, and localized fibrosis, suspecting a chronic specific inflammation, which included tuberculosis mass (Fig. 3b). Then, the patient was diagnosed with knee tuberculosis.
Patient was prescribed with isoniazid (10 mg/kg/day), pyrazinamide (30 mg/kg/day), rifampicin (15 mg/kg/day), ethambutol (15 mg/kg/day), and streptomycin (25 mg/kg/day) daily for 2 months followed the synovectomy procedure. Treatment was then continued for 9 months with isoniazid (10 mg/kg/day) and rifampicin (15 mg/kg/day). Clinical improvement was observed after eight months of treatments; it was clinically proven that the improvements on flexed and extended ability to 130  and -10 . The side effect of treatments did not really affect the patient's condition. After 1 year, the patient has shown no clinical symptoms with the exception of limited flexibility movement (maximal flexed ability 160 ), and there was an improvement of radiologic examinations. After a year, follow-up x-ray examinations on the chest showed scanty fibrotic in the upper pulmonary lobe. MRI was performed, and it showed the more prominent of the lytic lesion compared with the previous MRI without secondary infection (Fig. 4). The patient was suggested to attend physical rehabilitation to ameliorate his joint movement without arthroplasty procedure scheduled. This time, he has been work as before he suffered the disease without any serious limitation. Clinical and radiological followed up might be considered to detect the long term complication, including secondary osteoarthritis.