key: cord-0874314-vvapi4mm
authors: Priftis, Konstantinos; Prior, Massimo; Meneghetti, Leonardo; Mercogliano, Teresa; Bendini, Matteo
title: Alexia without agraphia in a post COVID-19 patient with left-hemisphere ischemic stroke
date: 2021-03-25
journal: Neurol Sci
DOI: 10.1007/s10072-021-05211-4
sha: 2f7ce261d3c9d930b1fe2fea27b8542f4ccddd1b
doc_id: 874314
cord_uid: vvapi4mm

nan

nasopharyngeal swab performed on October 14th was still positive. Chest CT scans showed interstitial pneumonia. Because his respiratory sings were worsened, on October 19, 2020, LM was transferred to the Pulmonary Disease Department of the same hospital. New molecular diagnostic tests for SARS-CoV-2, performed on October 28th and 30th, were negative.

On October 31st, 2020, LM complained of visual deficits within his right visual hemifield. Furthermore, he could no longer distinguish the letters of the alphabet or read single words and sentences. A comprehensive neurologic examination (November 5th, 2020) revealed the presence of a complete, right homonymous hemianopia and a mild deficit of the VII cranial nerve. All other sensorimotor functions were intact.

On November 10th, 2020, LM was admitted to the First General Medicine Department of Treviso Hospital. He was alert and fully oriented to time and space. He still showed signs of right homonymous hemianopia with macular sparing. FLAIR MRI performed on November 11th, 2020, revealed the presence of a left occipito-temporal ischemic stroke extending to the underneath white matter (Fig. 1 ). DTI documented an incomplete lesion to the splenium of the corpus callosum.

Comprehensive neuropsychological assessment was performed to investigate intact and impaired cognitive functions. LM's overall cognitive status was preserved for his age and education (see Table 1 ; Montreal Cognitive Assessment: MoCA [4] ; https://mfr.osf.io/render?url=https%3A%2F% 2Fosf.io%2Fbwge6%2Fdownload), even if he was unable to retrieve five common nouns after a short delay. Nonetheless, LM did not show signs of amnesia in everyday life activities. For instance, he was perfectly able to learn and recall the names of the clinicians and his scheduled activities.

LM performance was largely preserved on number processing tasks, except for transcoding written number words into Arabic digits. His ability to perform additions, subtractions, and multiplications was intact (Table 2 [5] ; https://mfr. osf.io/render?url=https%3A%2F%2Fosf.io%2Fbwge6% 2Fdownload).

LM oral language abilities were highly preserved in everyday life. He was perfectly able to repeat aloud spoken words, non-words, and sentences. Thus, LM had intact phonemic perception, phonological short-term memory, and articulation. His oral comprehension was very mildly impaired for single words, but it was perfect for sentences. LM's prosody was intact, and agrammatism was absent. Furthermore, he was good at naming colours. Finally, his oral fluency was intact for letters F and A but impaired for letter S and the animal category ( LM was perfectly able to write on dictation both single letters and sentences. By contrast, his reading skills were severely impaired (correct: 1/10 words, 0/5 non-words, and 0/2 sentences). His written comprehension was also impaired. Because LM was impaired in reading both words and nonwords, his deficit should be localized at a processing level before the input orthographic lexicon and the grapheme-tophoneme conversion mechanism (e.g. graphemic analysis mechanisms).

Another point in favour of a peripheral impairment at the level of graphemic analysis was LM's inability to transcode written number words into Arabic digits. Note that this task requires only graphemic analysis given that transcoding a written number word to the respective Arabic digit does not require reading aloud the written number word. LM's difficulties in reading cannot be attributed to his hemianopia, because he was free to move his eyes, and there was no time limit to perform the tasks. Furthermore, LM's perfect ability to read aloud Arabic digits and to name colours ruled out the presence of peripheral visual impairment. Finally, LM was able to read correctly through the tactile modality, by using 3D letters.

LM showed alexia without agraphia (pure alexia), whereas the rest of his cognitive profile remained largely preserved. This pattern mirrors that reported by Priftis et al. (2020), who described LA, a patient with agraphia without alexia (pure agraphia). Thus, patients affected by COVID-19 and stroke can show highly isolated and focal cognitive deficits in the domain of written language. To the best of our knowledge, LA and LM are the first two cases with pure alexia or pure agraphia reported in patients affected by SARS-CoV-2.

Whether ischemic lesions reported in patients LM and LA were caused by SARS-CoV-2 remains an open question [6] . Nonetheless, the excellent medical history of LA and the overall good health status of LM render plausible the association between SARS-CoV-2 and ischemic stroke. Furthermore, it has been recently reported that the risk of ischemic stroke was double that observed in patients with SARS-CoV-1 or severe sepsis. In addition, the risk of ischemic stroke was eight times higher than that of patients with influenza [7] . Furthermore, other findings have suggested that ischemic strokes in patients with SARS-CoV-2 are more severe and disabling than those in non-SARS-CoV-2 patients [8] .

Note that neuropsychological disorders can be present even when SARS-CoV-2 is not active anymore. Indeed, LM resulted negative 3 days before the onset of his stroke. Nevertheless, his neuropsychological disorders appeared after virus neutralization and lasted for months. Thus, comprehensive neuropsychological assessment and rehabilitation should become the default choice for all patients showing cognitive dysfunction during or after SARS-CoV-2 infection [9, 10] .

Pattern of cognitive deficits in severe COVID-19

RM Flair scan showing an occipito-temporal hyperintense lesion extending to the white matter

COVID-19 presenting with agraphia and conduction aphasia in a patient with lefthemisphere ischemic stroke

Acquired dyslexia

Normative data for the Montreal Cognitive Assessment in an Italian population sample

Esame neuropsicologico per l'afasia

COVID-19: patients with stroke or risk of stroke

Stroke risk, phenotypes, and death in COVID-19: Systematic review and newly reported cases

Characteristics and outcomes in patients with COVID-19 and acute ischemic stroke: The Global COVID-19 Stroke Registry

Neuropsychological consequences of Covid-19

Neuropsychology in the times of COVID-19. The role of the psychologist in taking charge of patients with alterations of cognitive functions

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Acknowledgements We would like to thank LM for his participation to the study. We are grateful to Dr. Marco Domenico Bonifati (Director of the Neurology Unit, AULSS 2, Veneto, Italy) for referring the patient to us. This work was carried out within the scope of the project 'use-inspired basic research', for which the Department of General Psychology of the University of Padova has been recognized as 'Department of Excellence' by the Italian Ministry of University and Research.

Informed consent The patient gave his informed consent to participate to the study. The study was conducted according to the principles of the Declaration of Helsinki.

Ethical approval None