A pilot study evaluating 99mTc-anti-TNF-alpha scintigraphy in graves' ophtalmopathy patients with different clinical activity score

The present study describes the preliminary results of the use of 99mTc-anti-TNF-α scintigraphy as a new diagnostic approach to evaluate patients presenting with Graves' ophthalmopathy (GO). Patients (n=25) presenting at different inflammatory stages of GO and 10 healthy volunteers underwent 99mTc-anti-TNF-α scintigraphy. Images were obtained 15 min after the intravenous injection of 370 MBq (10 mCi) 99mTc-anti-TNF-α. Planar images were obtained in a 256×256 matrix (each lasting 5 min) and single photon emission computed tomography (SPECT) scan lasting 13 min. Regions of interest (ROI) were drawn on the orbit and cerebral hemispheres. The uptake of 99m Tc-anti-TNF-α in these regions was compared and positive scintigraphy established when the ROI was >2.5. In addition, uptake for each positive exam was scored as either slight (2.6-5.1), moderate (5.2-7.6), or high (>7.6). In this pilot study, 69 orbits were evaluated (1 patient had only 1 eye), and 27 had a positive CAS (≥3/7). Scintigraphies were positive in 38 orbits. Comparing the results of the exams with CAS, a high sensitivity and negative predictive values were determined for scintigraphy (96.3% and 96.7%, respectively). However, the specificity and the positive predictive values were 71.4% and 68.4%, respectively, with an accuracy of 81.2%. The exclusion of examinations that were slightly positive from the analysis resulted in an improvement in test accuracy (95.5%). The preliminary results suggest that 99mTc-anti-TNF-α scintigraphy is a promising procedure for the evaluation of active orbital inflammation in GO.

Radioactive synovectomy with (90) yttrium and (153) samarium hydroxyapatite in haemophilic joints: preliminary study on radiation safety

Most countries still do not achieve 1 IU of factor VIII/capita sufficient for survival. Although primary prophylaxis prevents synovitis, is not universally used. Chronic synovitis is treated with arthroscopy at expense of considerable amount of coagulation factors, and specialized surgeons. Radioactive synovectomy (RS) is a minimally invasive and cost effective alternative to arthroscopy, often considered first the option for persistent synovitis. Even without established causation with cancer, RS is avoided by some, due to this concern. We aim contributing to the understanding of RS safety regarding malignancy, presenting a large number of treated patients, and a single case of cancer. Three centres in Brazil applied RS with (90) Yttrium Citrate, (90) Yttrium hydroxyapatite or (153) Samarium hydroxyapatite in haemophilic joints and performed a survey addressing cancer in these patients. Four hundred and eighty eight patients (ages 3-51) received 1-3 RS (total 842) and follow-up was 6 months to 9 years. One patient aged 14 years presented Ewing sarcoma, 11 months after RS. The tumour was treated successfully with surgery and chemotherapy. Causality of cancer by RS is improbable in this case. Accordingly, latency here is far below minimum 5-10 years for radio-induction of solid tumours. Moreover, ES is not a typically radio-induced tumour, even at high doses. In agreement with others, though recognizing limitations, this study suggests RS is safe regarding cancer induction. Synovitis is a known burden for patients. The decision of making reasonable usage of RS should be outweighed with the risks of leaving synovitis untreated.

⁹⁰Yttrium-hydroxyapatite: a new therapeutic option for radioactive synovectomy in haemophilic synovitis

Recurrent haemarthroses often lead to chronic synovitis in patients with haemophilia and von Willebrand disease. Radioactive synovectomy with yttrium-90 (⁹⁰Y) citrate is frequently used to treat this complication, usually with good results. Since 2006, the Nuclear Energy Research Institute (IPEN, Sao Paulo, Brazil) has produced hydroxyapatite particles labelled with ⁹⁰Y for radioactive synovectomy. The aim of this study was to compare the results achieved by both forms of ⁹⁰Y in the treatment of haemophilic synovitis. We included 221 joints from 136 patients (age range: 6-20 years), treated by one of the two radiopharmaceuticals, at the Hemocenter of Mato Grosso, Brazil. The outcomes analysed were the annual frequency of haemarthrosis, articular pain and joint range of motion before and 1 year after RS. Similar results were achieved regardless of whether ⁹⁰Y hydroxyapatite or ⁹⁰Y citrate was used, and results were independent of the joint type, age, gender, radiologic stage and presence of inhibitors. ⁹⁰Y hydroxyapatite appears to be equivalent to the reference product ⁹⁰Y citrate in the treatment of chronic synovitis associated with bleeding disorders.

Monitoring rheumatoid arthritis synovitis with 99mTc-anti-CD3

The aim of this study was to investigate the feasibility of using a monoclonal antibody (OKT3) labelled with technetium-99m (99mTc) to monitor disease activity in patients with rheumatoid arthritis. We evaluated 38 patients who were diagnosed with rheumatoid arthritis and classified as Classes II and III after functional assessment (according to the revised criteria specified by the American College of Rheumatology). Two sets of planar anterior images of the patients' wrists, metacarpophalangeal and interphalangeal joints, elbows, shoulders and knees joints were obtained 1 h and 3 h after the injection of 99mTc-OKT3. The scintigraphic findings showed significant correlation (p<0.05) between the radiopharmaceutical accumulation of 99mTc-OKT3 and swollen joints, tender joints and the visual analogue scale. They were able to differentiate patients in remission from patients with active synovitis, according to DAS 28. In contrast, there was no correlation between the radiopharmaceutical accumulation and the patients' age, gender, duration of disease or erythrocyte sedimentation rate. A relatively high disease activity score of 28 joints (4.08+/-1.74) was found in the majority of patients. In conclusion, 99mTc-OKT3 scintigraphy is a reliable and objective method for detecting synovial activity, and can be used to observe disease prognosis.