F-18-fluorodeoxyglucose (FDG) positron emission tomography/CT is an important whole-body imaging tool in the oncology and widely utilized to stage and restage various malignancies. The findings of significant focal accumulation of FDG in the lung parenchyma in the absence of corresponding CT abnormalities are related to the lung microembolism and known as hot-clot artifacts. Herein we present two cases with focal FDG uptake in the lung parenchyma with no structural lesions on the CT scan and discuss the possible mechanisms.
*Artifacts ; False Positive Reactions ; Female ; Fluorodeoxyglucose F18/*administration & dosage/diagnostic use/pharmacokinetics ; Humans ; Lung/metabolism/radiography/*radionuclide imaging ; Male ; Middle Aged ; Multimodal Imaging/methods ; Positron-Emission Tomography/*methods ; Pulmonary Embolism/radiography/*radionuclide imaging ; Radiopharmaceuticals/*administration & dosage/diagnostic use/pharmacokinetics ; Tomography, X-Ray Computed/methods ; Young Adult

BACKGROUND AND OBJECTIVES: Non-dipper hypertension is frequently accompanied by endothelial dysfunction and activation. Previous studies suggested that endocan may be a novel endothelial dysfunction marker. This study aims to investigate the association between circadian blood pressure (BP) pattern and plasma endocan levels together with high-sensitivity C-reactive protein (hsCRP) in patients with newly diagnosed untreated hypertension. SUBJECTS AND METHODS: Twenty-four hour ambulatory blood pressure monitoring was recorded in 35 dipper, 35 non-dipper hypertensives and 35 healthy controls. Endocan levels were measured by enzyme-linked immunosorbent assay. Serum levels of hsCRP were also recorded. RESULTS: Despite similar daytime and 24-hour average BP values between dippers and non-dippers, statistically significant high nocturnal BP was accompanied by a non-dipping pattern (Systolic BP: 132±9 vs. 147±11 mmHg; Distolic BP: 80±7 vs. 91±9 mmHg, respectively, p<0.001 for both). Non-dipper patients demonstrated higher endocan levels compared to dippers and normotensives (367 (193-844) pg/mL, 254 (182-512) pg/mL and 237 (141-314) pg/ml, respectively, p<0.001). HsCRP levels were significantly higher in non-dippers than the other groups (p=0.013). In a multivariate logistic regression analysis, endocan (p=0.021) and hsCRP (p=0.044) were independently associated with a non-dipping pattern. CONCLUSION: Elevated endocan levels were found in non-dipper groups. Endocan and hsCRP were found to be independently associated with a non-dipping pattern. We suggest that elevated levels of endocan in non-dipper hypertensive patients might be associated with a longer duration of exposure to high BP. These results point to the possible future role of endocan in selection of hypertensive patients at higher risk or target organ damage.
Blood Pressure ; Blood Pressure Monitoring, Ambulatory ; C-Reactive Protein ; Enzyme-Linked Immunosorbent Assay ; Humans ; Hypertension* ; Logistic Models ; Plasma