[(123)I]-Ioflupane SPECT in combination with MIBG myocardial scintigraphy in Parkinson's disease: a case series study.

Metaiodobenzylguanidine (MIBG) myocardial scintigraphy is widely accepted as a beneficial tool for differentiating Parkinson's disease (PD) from other Parkinson-related disorders (PRD). In Japan, dopamine transporter (DAT) imaging, which can evaluate presynaptic degeneration of dopamine neurons, has been applied in clinics since 2014. The present study investigated the utility of [(123)I]-Ioflupane single photon emission computed tomography (SPECT) combined with MIBG myocardial scintigraphy for the diagnosis of PD. We performed [(123)I]-Ioflupane SPECT and MIBG myocardial scintigraphy in 63 PD patients, 8 PRD patients and 1 essential tremor patient, and obtained the specific binding ratio (SBR [cut-off: 4.5]) and the heart-to-mediastinum ratio (H/M [cut-off: 2.2]). In 70% of the PD patients, both parameters were significantly reduced. In 22% of the PD patients, the SBR was smaller than 4.5 with normal H/M, and H/M was less than 2.2 with normal SBR in 5% of all subjects. Either the SBR or H/M was significantly reduced in 97% of the study population. The SBR showed low disease specificity to PD (11%), and the SBR and H/M negatively correlated with disease duration. These findings indicate that [(123)I]-Ioflupane SPECT combined with MIBG myocardial scintigraphy can improve the detection rate of PD. However, careful interpretation of these results is required because [(123)I]-Ioflupane SPECT poorly differentiates PD from PRD. Progression of PD may reflect the gradual reduction of isotope accumulation, hence, both [(123)I]-Ioflupane SPECT and MIBG myocardial scintigraphy should be tested repeatedly even in clinically suspected PD cases showing negative results.

[Case of Isaacs' syndrome associated with Hashimoto disease].

We report a case of Isaacs' syndrome associated with Hashimoto disease. A 26-year-old woman, who had a past history of Hashimoto disease, complained of involuntary movements and muscle cramp in lower extremities. On examination, myokymia was seen in lower extremities. Myokymia was observed even during sleep, and worsened by exercise or bathing. The antibody against voltage-gated potassium channel (VGKC) was positive. Myokymic discharges were recorded with needle EMG in lower extremities. The patient was diagnosed as having Isaacs' syndrome. Isaacs' syndrome tends to be associated with some other autoimmune diseases. We discussed the correlation between Isaacs' syndrome and autoimmune disease. About 23% of Isaacs' syndrome cases are associated with some other autoimmune diseases and myasthenia gravis was most common. This is the first case report of Isaacs' syndrome associated with Hashimoto disease in Japan.

Flare-up of dermatomyositis along with recurrence of breast cancer.

Dermatomyositis is an idiopathic inflammatory myopathy with characteristic cutaneous manifestations. The association between dermatomyositis and malignancy is becoming more clearly delineated. A sort of dermatomyositis is thought to be paraneoplastic syndrome and dermatomyositis may follow clinical course of malignancy. We report a 68-year-old woman with dermatomyositis, whose clinical onset of dermatomyositis was apparently concomitant with breast cancer. Dermatomyositis had settled down and oral steroid could be tapered after the resection of breast cancer. Creatine kinase value was elevated before the detection of the first and second recurrence and in the terminal state. At the second recurrence, skin lesions and creatine kinase value had flared up and immediate metastatic check-up revealed the recurrence. Our case shows dermatomyositis, which was thought to be paraneoplastic syndrome, that followed clinical course of malignancy and suggests immediate check-up is needed for early detection of recurrence when dermatomyositis flares up after the resection of the malignancy.