ABSTRACT
Introduction SARS-CoV-2 is a neurotropic, mucotropic, and sialotropic virus that can affect the salivary glands' function, taste sensations, smell, and oral mucosa integrity.1 The oral cavity is a perfect habitat for SARS-CoV-2 invasion due to the special affinity the virus has for cells with angiotensinconverting enzyme (ACE2) receptors, such as those from the respiratory tract, oral mucosa, tongue, and salivary glands. Aphthous lesions with necrosis and hemorrhagic crusts have been described to manifest more regularly in older adults with immunosuppression and severe COVID-19 infection;one hypothesis for the development of aphthous lesions and/or ulcers is given due to the ACE2 receptor and the SARS-CoV-2 interaction, which could alter the epithelial lining of salivary glands and keratinocytes, causing lesions in the oral cavity.4 At the same time, different etiological factors such as infections, immune system alterations, and direct trauma to the oral mucosa or epithelium,5 may be related to the stress of a prolonged hospital stay.6 Including pressure in the oral cavity conditioned by the prone position, malposition of the endotracheal tube (mainly in the corners of the lips),7 medication-related nutritional deficiencies8 such as lopinavir, and ritonavir, oseltamivir, hydroxychloroquine, among others.9-12 Thrombotic vasculopathy secondary to COVID-19 has also been described, induced by system mediators in the microvascular walls, which impairs endothelial cells, and activates coagulation factors13 and a possible hypersensitivity reaction of the mucosa to the presence of SARS-CoV-2 in the epithelium14,15;there is also the hypothesis that it could be associated with an exanthem pattern induced by the inflammatory action of the SARSCoV-2 virus,16 presented as increased levels of cytokines (including interleukin-1, tumor necrosis facto-a), and arachidonic acid metabolites (prostaglandins) secondary to the stem cell factor production and the basic fibroblast growth factor of keratinocytes from the basal layer, in relation to post-inflammatory pigmentations that could appear in areas previously affected by trauma or chronic inflammation.17 Oral manifestations in COVID-19 patients appear, on many occasions, even before respiratory symptoms, although exanthematic lesions observed in COVID-19 patients can also be observed in other viral processes. Physical examination revealed a patient in a supine position with orotracheal intubation and orogastric tube, with aphthous-type ulcers, some of them had blood crusts of different sizes on the lower lip (both skin and mucosa), dorsum, and lateral edge of the tongue, gum, and vestibular fornix (Figure 3). Initial physical examination shows the patient in a supine position supported by high-flow nasal prongs, upper and lower lips edema and ulcer-like lesions with hematic crusts on both lips (Figure 4), topical management with steroids and GELCLAIRE® Oral Gel (glycyrrhetinic acid and polyvinylpyrrolidone) is observed.
ABSTRACT
PURPOSE: Cerebral amyloid angiopathy (CAA) is a common neuropathological finding and clinical entity that occurs independently and with co-existent Alzheimer's disease (AD) and small vessel disease. We compared diffusion tensor imaging (DTI) metrics of the fornix, the primary efferent tract of the hippocampus between CAA, AD and Mild Cognitive Impairment (MCI) and healthy controls. METHODS: Sixty-eight healthy controls, 32 CAA, 21 AD, and 26 MCI patients were recruited at two centers. Diffusion tensor images were acquired at 3 T with high spatial resolution and fluid-attenuated inversion recovery (FLAIR) to suppress cerebrospinal fluid (CSF) and minimize partial volume effects on the fornix. The fornix was delineated with deterministic tractography to yield mean diffusivity (MD), axial diffusivity (AXD), radial diffusivity (RD), fractional anisotropy (FA) and tract volume. Volumetric measurements of the hippocampus, thalamus, and lateral ventricles were obtained using T1-weighted MRI. RESULTS: Diffusivity (MD, AXD, and RD) of the fornix was highest in AD followed by CAA compared to controls; the MCI group was not significantly different from controls. FA was similar between groups. Fornix tract volume was â¼ 30% lower for all three patient groups compared to controls, but not significantly different between the patient groups. Thalamic and hippocampal volumes were preserved in CAA, but lower in AD and MCI compared to controls. Lateral ventricular volumes were increased in CAA, AD and MCI. Global cognition, memory, and executive function all correlated negatively with fornix diffusivity across the combined clinical group. CONCLUSION: There were significant diffusion changes of the fornix in CAA, AD and MCI compared to controls, despite relatively intact thalamic and hippocampal volumes in CAA, suggesting the mechanisms for fornix diffusion abnormalities may differ in CAA compared to AD and MCI.