Importance of Awareness and Careful Follow-Up of Suspected IgG4-Related Periaortitis.

IgG4-related disease may cause large vessel vasculitis, which often affects males in their 60s. Here, we report a case of suspected IgG4-related periaortitis in a 76-year-old man with lower left-side chest pain and hypertension based on computed tomography findings of thickened lesions surrounding the abdominal aorta and mesenteric arteries after ruling out acute cardiovascular diseases. His serum IgG4 levels were high, but the C-reactive protein and D-dimer levels were within normal limits. Because IgG4-related periaortitis was suspected, the patient was carefully monitored for blood pressure control, inflammatory markers, and renal function. Steroid therapy was not initiated, however, due to the difficulties performing a biopsy targeting periaortitis to obtain a definitive diagnosis and possible severe complications. During follow-up observation, IgG4-related kidney disease was suspected based on a slight increase in the serum creatinine levels and a renal biopsy was considered. Just before performing the renal biopsy, we observed left renal hydronephrosis caused by spreading retroperitoneal fibrosis. Immediate ureteral stent implantation and initiation of steroid therapy successfully improved the renal function and decreased the serum IgG4 level, respectively. Although relatively rare, IgG4-related periaortitis/periarteritis and retroperitoneal fibrosis should be considered in the differential diagnosis of aortic diseases, even after ruling out serious major acute cardiovascular diseases. Cardiologists should also be aware of the possible progression and systemic spread of this disease.

Arterial spin-labeling MR imaging in moyamoya disease compared with SPECT imaging.

OBJECTIVE: Arterial spin-labeling (ASL) is a noninvasive magnetic resonance (MR) imaging method used to obtain brain perfusion information on various cerebrovascular diseases. We retrospectively compared the use of ASL-MRI and single-photon emission CT (SPECT) imaging to determine absolute cerebral blood flow (CBF) in moyamoya disease. MATERIALS AND METHODS: CBF examinations using ASL-MRI on 3-T MRI and SPECT imagings with iodine-123-N-isopropyl-p-iodoamphetamine at resting (rest-IMP) and after acetazolamide challenge (ACZ-IMP) were performed on 12 patients with moyamoya disease (men, 5; women, 7; age range/average (year), 7-66/35.0). The CBF values determined by ASL-MRI (ASL-value), rest-IMP (rest-IMP-value), and ACZ-IMP (ACZ-IMP-value) of cerebral hemispheres (24 sides) were measured with normalized CBF maps created from data of those 3 perfusion imaging methods. Cerebrovascular reactivity (CVR) was calculated as follows: {(ACZ-IMP-value)-(rest-IMP-value)}/(rest-IMP-value)×100 (%). The ASL-value was compared with the rest-IMP-value, ACZ-IMP-value, and CVR. RESULTS: The ASL-value, rest-IMP-value, ACZ-IMP-value, and CVR (average±standard deviation) were 26.6±14.8 (mL/100 g/min), 27.5±6.4 (mL/100 g/min), 37.1±13.2 (mL/100 g/min), and 35.9±44.3 (%), respectively. Significant relationships between the ASL-value versus (vs.) the rest-IMP-value (rs=0.500, p<0.05), the ASL-value vs. the ACZ-IMP-value (rs=0.863, p<0.01), and the ASL-value vs. the CVR (rs=0.699, p<0.01) were observed. CONCLUSION: Although the ASL-value was lower than the rest-IMP-value, the significant relationship between the ASL-value and the rest-IMP-value may suggest that perfusion imaging by ASL-MRI could be used to recognize the condition of brain perfusion. In particular, the stronger correlation coefficient between the ASL-value and ACZ-IMP-value might suggest that perfusion imaging by ASL-MRI could show the potentially dangerous zone for ischemia.