Skin and Arterial Wall Deposits of 18F-NaF and Severity of Disease in Patients with Pseudoxanthoma Elasticum

Abstract

Pseudoxanthoma elasticum (PXE) is a genetic disease characterized by the calcification of elastin fibers. Our aim was to quantify vascular calcification in the arteries and the deposition of 18F-sodium-fluoride (18F-NaF) in the skin and vessel walls with positron emission tomography/computed tomography. This was an observational study including 18 patients with PXE. Vascular calcification was measured in Agatston units, and deposition in the skin and vessel walls was shown using target-to-background ratio (TBR). Severity of the disease was scored by Phenodex. We found higher vascular calcification in the popliteal, femoral, and aortic arch vessels compared to other vascular regions; however, the uptake of radiotracer was the highest in the aorta and femoral arteries. In the skin, the highest uptake was observed in the neck and the axillae. There was no significant association between 18F-NaF deposition in the arteries or skin and the global Phenodex score. In contrast, the Phenodex score was significantly associated in univariate analyses with the averaged vascular calcium score (p < 0.01). In the neck, patients with higher skin Phenodex scores exhibited higher radiotracer uptake. As a conclusion, because vascular calcification is physiological, our data suggested that the detection of cutaneous (neck) 18F-NaF deposits might serve to monitor the calcification process in the short-term for patients with PXE.

Assessment of Inflammation and Calcification in Pseudoxanthoma Elasticum Arteries and Skin with 18F-FluroDeoxyGlucose and 18F-Sodium Fluoride Positron Emission Tomography/Computed Tomography Imaging: The GOCAPXE Trial

“…In the 23 PXE patients 18F-NaF activity was higher in the neck and axillary folds than in the lumbar skin region, suggesting active calcification on damaged skin. These results are consistent with those recently published where patients with higher skin Phenodex scores exhibited higher 18F-NaF uptake in the neck [32]. In the vascular system 18F-NaF uptake was observed exclusively in the aorta and the femoral arteries, substantiating our previous characterization of vulnerability to PXE damage in these regions [1,23,33].…”

Genotype-phenotype correlation in pseudoxanthoma elasticum

“…Quantification of pseudoxanthomas based on the number of affected locations is a very rough estimate of the skin involvement in PXE. Currently, new in vivo methods to quantify elastin degradation, using two-photon microscopy [33], or calcification of the skin using sodium fluoride PET/CT (NaF-PET/CT) are being developed [34]. Future research might want to look into the genotype-phenotype correlation based on these more sophisticated methods.…”

NaF-PET Imaging of Atherosclerosis Burden

“…Forty-five articles were included in this review [ 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 , 35 , 36 , 37 , 38 , 39 , 40 , 41 , 42 , 43 , 44 , 45 , 46 , 47 , 48 , 49 ] ( Figure 1 ), to which were added selected articles on methodological and other aspects. Findings in the articles are summarized in the following sections and in Tables S1–S6 in the Supplementary Material .…”