A 75-year-old male, a retired worker,was admitted to our hospital with recurrent joint pain for more than 1 year, fever for 6 months and recurrence for one week. Both large and small joints were involved, such as the left ankle, the third metacarpophalangeal joint of the right hand, the right shoulder, and the left wrist. The joint pain affected the patient’s activity. One year prior, he repeatedly visited the orthopaedic clinic and intermittently took etoricoxib. Six months prior to this presentation, the patient was admitted to our hospital with fever. A complete blood count showed an increased white blood cell (WBC) count of 30,500/µl (neutrophil: 90.1%) with mild anaemia (haemoglobin: 11.9 g/dl) and a platelet count of 194×109/l. The laboratory data further showed inflammation markers [C-reactive protein (CRP): 140.79 mg/dl, erythrocyte sedimentation rate (ESR): 34 mm/hr, procalcitonin (PCT): 0.48 ng/ml and ferritin: 460.8 ng/ml]. Tests for rheumatoid factors and cyclic citrullinated peptide (CCP) IgG antibodies and the antinuclear antibody titre were negative. Computed tomography (CT) of the chest and abdomen revealed postoperative changes indicating liver cancer. Colour ultrasound of the heart was normal. During the hospital stay, the patient had repeated episodes of fever and joint pain; a bone marrow puncture and biopsy were performed, and the results were normal. Dual-energy CT for gout indicated a few urate crystals deposited in the bilateral radiocarpal joints, while the blood uric acid levels were normal. Infectious fever and gout were considered, and the patient was successively treated with piperacillin/tazobactam sodium (4.5 g q8h intravenously for 11 days), imipenem (1.0 g q8h intravenously for 6 days), linezolid (0.6 g q12h orally for 10 days) and loxoprofen (60 mg q12h orally for 3 days). The patient improved and was discharged on the 24th day of hospitalization.
Two months prior to this presentation, the patient was admitted to our hospital again with similar symptoms. The laboratory data were as follows: WBC count: 16,600/µl (neutrophil: 92.1%), CRP: 97.3 mg/l,ESR: 79 mm/h, and PCT: 0.09 ng/ml. Human leucocyte antigen-B27 (HLA-B27), tuberculin test and T-SPOT-TB were negative. Abdominal CT indicated multiple new low-density foci in the liver, and enhanced magnetic resonance imaging (MRI) of the upper abdomen showed multiple scattered enhanced nodules in the liver, indicating that metastasis should be considered (Fig. 1A, B). However, positron emission tomography-computed tomography (PET-CT) showed that inflammatory lesions should be considered first. The patient was treated with levofloxacin (0.5 g qd intravenously for 5 days) and etoricoxib (60 mg q12h orally for 7 days). The patient was discharged on the 7th day of hospitalization.
The patient had a nonspecific ailment, chronic viral hepatitis B and long-term use of lamivudine. He had a history of HCC surgery 11 years ago and received three cycles of postoperative chemotherapy. No tumour recurrence was found in regular re-examinations, and the last follow-up was 2 years ago. He also had a history of "hypertension, type 2 diabetes" of more than 10 years, both of which were well controlled with drugs.
At this presentation, the physical examination showed that the skin on the right third metacarpophalangeal joint was red and swollen with obvious tenderness, and there was tenderness in the right shoulder, lumbosacral region, lower back, left wrist joint and left ankle joint; in addition, there were also several areas of muscle tenderness, such as the lateral muscle of the left thigh. The blood routine was as follows: WBC: 36,800/µl (neutrophil: 95.6%), CRP: 261.86 mg/l, PCT: 0.11 ng/ml. The enhanced MRI of the upper abdomen was repeated and revealed that many of the nodules in the liver disappeared, except for the nodule in segment VI (Fig. 1C, D). Because of the muscle tenderness, we conducted a further physical examination and found that the patient had decreased proximal muscle strength and muscle weakness for several months. Although multiple creatinine kinase (CK)/creatine kinase-MB (CK-MB) tests were normal, a myositis antibody test was completed and was positive for anti-OJ antibodies. Enhanced MRI of the left thigh and lower leg showed abnormal T2 signals in the medial thigh muscle group (Fig. 2). Muscle biopsy suggested myositis (Fig. 3). The patient did not have the clinical manifestations of ILD by chest high-resolution computed tomography (HRCT) or mechanic’s hand.
The patient was eventually diagnosed with ASS and treated with prednisone 30mg/day for 10 days (treatment stopped by the patient), after which the condition was in remission. The patient intermittently took antipyretic analgesics and had occasional joint pain and fever. After 1 year of follow-up, enhanced MRI of the upper abdomen showed a mass occupying the right hepatic lobe (segment VI) that had become enlarged, and recurrence was considered (Fig. 1E). Postoperative pathology showed HCC. After the operation, the patient's joint pain, fever and muscle weakness improved. At present, the patient has been followed up for nearly 3 years and has not been treated with drugs for ASS; his general condition is good, with no interstitial pneumonia(Fig. 4).