Shinji Ishimaru

Myocardial imaging with 18F-fluoro-2-deoxyglucose positron emission tomography and magnetic resonance imaging in sarcoidosis

PurposeDespite accumulating reports on the clinical value of 18F-fluoro-2-deoxyglucose positron emission tomography (18F-FDG PET) and magnetic resonance imaging (MRI) in the assessment of cardiac sarcoidosis, no studies have systematically compared the images of these modalities.MethodsTwenty-one consecutive patients with suspected cardiac sarcoidosis underwent cardiac examinations that included 18F-FDG PET and MRI. The association of 18F-FDG PET and MRI findings with blood sampling data such as serum angiotensin converting enzyme levels was also evaluated.ResultsEight of 21 patients were diagnosed as having cardiac sarcoidosis according to the Japanese Ministry of Health and Welfare Guidelines for Diagnosing Cardiac Sarcoidosis. Sensitivity and specificity for diagnosing cardiac sarcoidosis were 87.5 and 38.5%, respectively, for 18F-FDG PET, and 75 and 76.9%, respectively, for MRI. When the 18F-FDG PET and MRI images were compared, 16 of 21 patients showed positive findings in one (n = 8) or both (n = 8) of the two modalities. In eight patients with positive findings on both images, the distribution of the findings differed among all eight cases. The presence of positive findings on 18F-FDG PET was associated with elevated serum angiotensin-converting enzyme levels; this association was not demonstrated on MRI.ConclusionsBoth 18F-FDG PET and MRI provided high sensitivity for diagnosing cardiac sarcoidosis in patients with suspected cardiac involvement, but the specificity of 18F-FDG PET was not as high as previously reported. The different distributions of the findings in the two modalities suggest the potential of 18F-FDG PET and MRI in detecting different pathological processes in the heart.

Addition of oral sildenafil to beraprost is a safe and effective therapeutic option for patients with pulmonary hypertension.

Although sildenafil, an oral phosphodiesterase type-5 inhibitor, may offer benefits in the pharmacological management of pulmonary hypertension (PH), safety and effectiveness have not been studied during coadministration with beraprost, an oral prostacyclin analogue. To address this issue, we administered oral beraprost (40 μg) on day 1 and beraprost (40 μg) plus sildenafil (25 mg) on days 2 to 6 patients with moderate to severe PH. Although sildenafil plus beraprost produced transient flushing in 2 of 6 patients, systemic hemodynamics and arterial and venous gas analyses were similar in comparisons between the 2 treatment groups. In contrast, sildenafil plus beraprost therapy resulted in a 2.2-fold greater reduction in mean pulmonary arterial pressure and a 1.6-fold greater reduction in pulmonary vascular resistance compared with beraprost alone, and reductions in these parameters persisted longer with combination therapy than with beraprost alone. Addition of oral sildenafil to beraprost appears to represent a safe and effective therapeutic option, at least in the acute phase, for patients with pulmonary hypertension.

Promoter polymorphism in the macrophage migration inhibitory factor gene is associated with obesity.

Objective:To explore the association of promoter polymorphisms of macrophage migration inhibitory factor (MIF) gene with obesity.Subjects:In total, 213 nondiabetic Japanese subjects. They were divided into three groups according to World Health Organization definitions: lean (body mass index (BMI) <25 kg/m2), overweight (25⩽BMI<30 kg/m2) and obese (BMI⩾30 kg/m2).Methods:We examined two polymorphic loci in the MIF gene in the subjects: a single-nucleotide polymorphism at position −173 (G/C) and a CATT-tetranucleotide repeat polymorphism at position −794, which both can affect promoter activity in different cells.Results:We detected four alleles: 5-, 6-, 7- and 8-CATT at position −794. Genotypes without the 5-CATT allele (X/X, X refers to 6-, 7- or 8-CATT alleles) were more common in obese subjects than in lean or overweight groups (P=0.013). The X-CATT allele was more frequent in obese subjects than in lean or overweight subjects (P=0.030). In contrast, −173G/C was not associated with obesity. Among the haplotypes of the two promoter polymorphisms, G/5-CATT ((−173G/C)/(−794[CATT]5–8)) was associated with a decreased risk of obesity (P=0.025) and G/6-CATT with an increased risk of overweight (P=0.028).Conclusion:Promoter polymorphism in the MIF gene is linked with obesity.