Arterial involvement in Fabry disease: state of the art and future diagnostic purposes.

Anderson-Fabry disease (FD) is a rare genetic, progressive, and multi-systemic condition, with X-linked inheritance. This is caused by pathogenic variants in the GLA gene, coding for the lysosomal enzyme called alpha-galactosidase A (aGLA), responsible for the cleavage of globotriaosylceramide (Gb3). The reduced or absent activity of aGLA causes the intracellular accumulation of Gb3, particularly in smooth and endothelial muscle cells, which causes cellular dysfunction. The main organs involved are the central nervous system, heart, and kidneys. However, being a ubiquitous enzyme, FD disease must be considered a systemic disease involving the peripheral nervous system, ocular and audio-vestibular systems. Also, the vascular district is damaged but the pathophysiology of vasculopathy in FD is not yet entirely understood. In literature, many vascular diagnostic tests were used to evaluate this specific involvement in FD, i.e., carotid intima media thickness (cIMT), arterial stiffness (AS), flow-mediated dilation (FMD) and atherosclerotic plaques; evaluation of vascular calcifications in FD patients is not presently available. In this review, we examined the current available literature on vascular aspects in FD. Moreover, we presented our global vascular evaluation, based on Radio Frequency Duplex Ultrasound (RF-DU), plaques, and vascular calcifications, to apply to FD patients.

Necrotic tumor versus brain abscess: importance of amino acids detected at 1H MR spectroscopy--initial results.

PURPOSE: To assess the usefulness of the 0.9-ppm peak from amino acids (-CH3 moieties from valine, leucine, and isoleucine) for the differentiation of brain abscesses and tumors at in vivo hydrogen 1 magnetic resonance (MR) spectroscopy. MATERIALS AND METHODS: Amino acid concentrations were determined in vitro in 13 purulent samples from brain and nonbrain tissues and in nine aseptic fluids from necrotic brain tumors at two-dimensional (2D) 1H MR spectroscopy and liquid chromatography. Thirty-four patients with cystic intracerebral mass lesions (28 tumors, six abscesses) were examined at 1H MR spectroscopy in vivo. RESULTS: Amino acids were identified in vitro in both purulent and aseptic samples. Amino acid concentrations measured in the aseptic fluids at both liquid chromatography and 2D MR spectroscopy were far below the detection threshold of in vivo 1H MR spectroscopy. Quantitative results obtained at 2D MR spectroscopy showed no overlap in the ranges of amino acid concentrations in purulent and aseptic samples. In vivo, the proton spectra obtained with a 136-msec echo time (TE) revealed amino acids (inverted peak at 0.9 ppm) in only the abscesses. CONCLUSION: The detection of amino acid resonance at 0.9 ppm at in vivo 1H MR spectroscopy (136-msec TE) is a promising tool for distinguishing bacterial abscesses and cystic brain tumors.