Yoshihito Yamada

Long fasting is effective in inhibiting physiological myocardial 18F-FDG uptake and for evaluating active lesions of cardiac sarcoidosis

BackgroundF-fluorodeoxyglucose (FDG) positron emission tomography (PET) is a promising modality for detecting active lesions of cardiac sarcoidosis (CS). However, determining whether 18F-FDG uptake in the myocardium is physiological is challenging due to metabolic shift in myocardial cells. Although methods for inhibiting physiological myocardial 18F-FDG uptake have been proposed, no standard methods exist. This study therefore aimed to compare the effect of an 18-h fast (long fasting (LF)) with heparin loading plus a 12-h fast (HEP) before 18F-FDG PET scan.MethodsWe analyzed the effects of LF and HEP on the inhibition of physiological myocardial 18F-FDG uptake in healthy subjects (18 in HEP and 19 in LF) and in patients with known or suspected CS (96 in HEP and 69 in LF). In CS, the lower uptake of 18F-FDG in the myocardium was evaluated. A visual four-point scale was used to assess myocardial 18F-FDG uptake in comparison with hepatic uptake (1 lower, 2 similar, 3 somewhat higher, 4 noticeably higher).ResultsMyocardial 18F-FDG uptake was 1.68 ± 1.06 in LF and 3.17 ± 1.16 in HEP in healthy subjects (p < 0.0001), whereas it was 1.48 ± 0.99 in LF and 2.48 ± 1.33 in HEP in CS patients (p < 0.0001). Logistic regression and regression trees revealed the LF was the most effective in inhibiting myocardial 18F-FDG uptake. In addition, serum free fatty acid levels on intravenous 18F-FDG injection were a possible biomarker.ConclusionsLF is effective in inhibiting myocardial 18F-FDG uptake, and consequently, it could be useful for evaluating active lesions of CS in 18F-FDG PET images.

Obstructive Sleep Apnea-hypopnea Syndrome Patients with Overweight and Hypertension in a Japanese Workplace

Obstructive Sleep Apnea‐hypopnea Syndrome Patients with Overweight and Hypertension in a Japanese Workplace: Ken Okabayashi, et al. JR East Health Promotion Center, East Japan Railway Company—The objective of this study was to determine the relationship between obstructive sleep apnea‐hypopnea syndrome (OSAHS) and overweight combined with hypertension and to examine whether OSAHS in conjunction with overweight and hypertension is associated with daytime sleepiness. In a Japanese workplace of 28,636 employees, 368 men (19–62 yr old), who were anxious regarding their OSAHS symptoms, underwent home pulse oximetry. Of these, 153 men subsequently underwent all‐night polysomnography (PSG), and OSAHS was diagnosed in 149. We next classified these 149 men into the following groups: A [Overweight (–)/Hypertension (–), n=41], B [Overweight (–)/ Hypertension (+), n=15], C [Overweight (+)/ Hypertension (–), n=46], and D [Overweight (+)/ Hypertension (+), n=47]. The Epworth Sleepiness Scale (ESS) was used to evaluate daytime sleepiness and the apnea‐hypopnea index (AHI) was used to evaluate the severity of OSAHS. The averages of the ESS score and the AHI were compared in each group. Both the average ESS scores and the percentage of ESS scores ≥11 were not significantly different among the groups. The average AHI of group D was the highest among all of the groups and that of group C was significantly higher than those of groups A and B. In all the groups, the OSAHS patients with overweight and hypertension in this study had the highest AHI. The level of daytime sleepiness evaluated by the ESS in this study was almost the same in the OSAHS patients regardless of the degree of overweight or hypertension. These observations suggest that it is necessary to positively recommend PSG to men who are suspected of having OSAHS with overweight and hypertension, even if they do not have daytime sleepiness.

Clinical Course and Changes in High-Resolution Computed Tomography Findings in Patients with Idiopathic Pulmonary Fibrosis without Honeycombing

Some patients with idiopathic pulmonary fibrosis (IPF) do not have honeycombing on high-resolution computed tomography (HRCT) at their initial evaluation. The clinical course and sequential changes in HRCT findings in these patients are not fully understood. We reviewed the cases of 43 patients with IPF without honeycombing on initial HRCT from institutions throughout Japan. All patients were diagnosed with IPF based on a surgical lung biopsy. Multidisciplinary discussions were held five times between 2011 and 2014, to exclude alternative etiologies. We evaluated the sequential changes in HRCT findings in 30 patients with IPF. We classified these 30 patients into three groups based on their HRCT patterns and clarified the clinical characteristics and prognosis among the groups. The patterns of all 30 patients on initial HRCT corresponded to a possible usual interstitial pneumonia (UIP) pattern which was described in the 2011 International Statement. On long-term follow-up (71.0±38.7 standard deviation [SD] months), honeycombing was seen in 16 patients (53%, the HoneyCo group); traction bronchiectasis or cysts without honeycombing was observed in 12 patients (40%, the NoHoneyCo group), and two patients showed no interval change (7%, the NoChange group) on HRCT. The mean survival periods of the HoneyCo and NoHoneyCo groups were 67.1 and 61.2 months, respectively (p = 0.76). There are some patients with IPF whose conditions chronically progress without honeycombing on HRCT. The appearance of honeycombing on HRCT during the follow-up might not be related to prognosis.

Respiratory bronchiolitis and lung carcinoma.

BACKGROUND Cigarette smoking is the primary causative factor for lung carcinoma and respiratory bronchiolitis (RB), particularly RB-associated interstitial lung disease (RB-ILD). However, the link between lung cancer and RB/RB-ILD remains undefined. We examined whether pathological fibrosis lesions exist simultaneously in patients with lung carcinoma because the fibrous lesions could be precancerous. METHODS Clinical, radiological, and pathological features were consecutively evaluated in 67 current smokers, 22 ex-smokers, and 35 nonsmokers who underwent surgical resection for lung carcinoma. The presence of interstitial changes was evaluated by high-resolution computed tomography (HRCT). The pathological examination focused on RB, RB with fibrosis, and coexistent interstitial changes. RESULTS RB with fibrosis was observed in 13/67 current smokers with centrilobular nodular and/or patchy ground-glass opacities patterns or emphysema on HRCT. RB without fibrosis was observed in 12/67 current smokers with a centrilobular pattern, emphysema, or a normal pattern on HRCT. The Brinkman smoking index was significantly higher in the RB with fibrosis group (1278±133) than in the RB without fibrosis group (791±131). No RB with/without fibrosis features were noted in nonsmokers or ex-smokers. Squamous cell carcinoma was observed in 11/13 patients with RB with fibrosis, whereas adenocarcinoma was observed in 7/12 patients with RB without fibrosis. CONCLUSIONS Squamous cell carcinoma located in peripheral areas was primarily observed in patients with RB with fibrosis, whereas adenocarcinoma was primarily observed in patients with RB without fibrosis. Interstitial fibrosis with RB caused by continuous heavy cigarette smoking may increase the risk of developing squamous cell carcinoma.

Pleuroparenchymal fibroelastosis diagnosed by multidisciplinary discussions in Japan

BACKGROUND Pleuroparenchymal fibroelastosis (PPFE) is a rare subset of idiopathic interstitial pneumonias. No large-scale clinical studies of PPFE have been published. The aim of the study was to clarify the clinical and physiological characteristics of PPFE in Japan METHODS: This was a retrospective, nationwide, and multicenter study in Japan. We reviewed 52 patients with PPFE, diagnosed after multidisciplinary discussions. RESULTS Flat chest index, defined as the ratio of anteroposterior diameter to transverse diameter of thoracic cage at the level of 6th thoracic vertebra, correlated positively with body mass index (BMI) (r = 0.340, p = 0.013) and percentage of predicted value of forced vital capacity (FVC %pred) (r = 0.355, p = 0.012), and negatively with the ratio of residual volume to total lung capacity (RV/TLC) (r = -0.312, p = 0.042). RV/TLC correlated negatively with BMI (r = -0.746, p < 0.0001) and FVC %pred (r = -0.507, p = 0.0005), and positively with age, and physiological variables (GAP) scores (r = 0.332, p = 0.030). The median survival time and the cumulative 5-year survival rate were 96 months and 58%, respectively. Patients with KL-6 level >600 (U/mL) survived shorter than those with <600 (p < 0.001). CONCLUSION Low BMI, decreased FVC and increased RV/TLC in PPFE may be related to the progression of flattened chest cage which impairs distension of chest cage at inspiration. Elevated serum levels of KL-6 suggest a poor prognosis of PPFE.