Thiamazole Pretreatment Lowers the (131)I Activity Needed to Cure Hyperthyroidism in Patients With Nodular Goiter.

CONTEXT: Relatively low radioiodine uptake (RAIU) represents a common obstacle for radioiodine ((131)I) therapy in patients with multinodular goiter complicated by hyperthyroidism. OBJECTIVE: To evaluate whether thiamazole (MTZ) pretreatment can increase (131)I therapeutic efficacy. DESIGN AND SETTING: Twenty-two patients with multinodular goiter, subclinical hyperthyroidism, and RAIU < 50% were randomized to receive either a low-iodine diet (LID; n = 10) or MTZ 30 mg/d (n = 12) for 42 days. Thyroid function and 24-hour RAIU were measured before and after treatment. Thyroid volume was evaluated by either magnetic resonance imaging or single photon emission computed tomography. RESULTS: Mean 24-hour RAIU increased significantly from 32 ± 10% to 63 ± 18% in the MTZ group (P < .001). Consequently, there was a 31% decrease in the calculated median therapeutic (131)I activity after MTZ (P < .05). No significant changes in 24-hour RAIU were observed after diet. In the MTZ group, median serum TSH levels increased significantly by 9% and mean serum free T4 and free T3 concentrations decreased by 22% and 15%, respectively, whereas no changes in thyroid function were observed in the LID group. Thyroid volume did not significantly change in either of the two groups. At 12 months after radioiodine treatment, median serum TSH was within the normal range in both groups. CONCLUSIONS: MTZ treatment before (131)I therapy resulted in an average 2-fold increase in thyroid RAIU and enhanced the efficiency of radioiodine therapy assessed at 12 months. MTZ pretreatment is therefore a safe, easily accessible alternative to recombinant human TSH stimulation and a more effective option than LID.

Disseminated tuberculosis mimicking ankylosing spondylitis.

Ankylosing spondylitis is a chronic inflammatory disorder affecting mainly the axial skeleton. Here we report a case of a man with a clinical suspicion of ankylosing spondylitis but with a persistence of increased inflammatory markers. In this case, (18)F-FDG-PET/CT revealed multiple hypermetabolic lesions in axial skeleton, lymph nodes, and the lung, suggestive of either disseminated tuberculosis or lymphoma. Histological analysis of the pulmonary lesion revealed mycobacterium tuberculosis. This case highlights, firstly, the importance of excluding other diagnoses in the presence of clinical picture of ankylosing spondylitis and high inflammatory markers and, secondly, the determining role of PET/CT.

Pericarditis revealing large vessel vasculitis.

Large vessels vasculitis and more specifically, Giant cell arteritis, is characterized by increased inflammatory markers, headaches and altered clinical status. Diagnosis is confirmed by biopsy of temporal arteries showing the presence of granuloma and vasculitis. We hereby report the case of a patient presenting initially as pericarditis and revealing large vessel vasculitis using FDG-PET.

Progressive osteoblastic bone metastases in breast cancer negative on FDG-PET.

Positron emission tomography using F-18 fluorodeoxyglucose positron emission tomography (FDG-PET) is increasingly used in breast cancer. The new generation cameras integrate PET and CT within the same camera, allowing the simultaneous assessment of the structural and metabolic aspects of disease. There is presently a controversy on the clinical significance of osteoblastic bone metastases in breast cancer which are not detected on FDG-PET. It has been suggested that these radiologically dense lesions represent the result of successful treatment of initially osteolytic lesions. We report a case of a 65-year-old woman with a suspicion of recurrent breast cancer based on an increasing serum tumor marker. Serial PET/CT showed progressive blastic bone metastases on the CT without FDG uptake. These lesions were confirmed by bone single photon emission computed tomography. This case report shows: first, that progressive osteoblastic lesions can lack FDG-avidity, leading to a false-negative PET; and secondly, that bone scintigraphy should not be replaced by FDG-PET/CT for the detection of bone metastases in breast cancer.