Two Pediatric Cases of Multisystem Inflammatory Syndrome with Overlapping Neurological Involvement Following SARS-CoV-2 Vaccination and Unknown SARS-CoV2 Infection: The Importance of Pre-Vaccination History

Abstract

The SARS-CoV-2 vaccine roll-out has been successful around the world. However, there are increasing concerns about adverse events. We report two pediatric cases of Multisystem-Inflammatory-Syndrome (MIS-C) with neurological involvement that occurred after SARS-CoV-2 vaccination and unknown recent SARS-CoV-2 infection. Brain magnetic resonance revealed mild-encephalopathy with reversible-splenial-lesion in both cases and complete resolution within 4 weeks. In conclusion, this report aims to describe rare emerging clinical entities that can help pediatricians to make an early diagnosis and to provide appropriate treatment. Multisystem-Inflammatory-Syndromes following COVID-19 vaccination remain rare events. When a history of a recent contact with SARS-CoV-2 is present, a careful evaluation by the clinicians in charge of immunization activities is suggested prior to proceeding with the vaccination.

Keywords: COVID-19 vaccination; mild encephalitis/encephalopathy with reversible splenial lesion (MERS); multisystem inflammatory syndrome following SARS-CoV-2 vaccination (MIS-V); multisystem inflammatory syndrome in children (MIS-C); severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).

Figure 1

Patient 1 MRI images at the onset showed a hyperintense lesion in the splenium of corpus callosum restricted in DWI/ADC (B,C), with only low- hyperintensity in FLAIR (A) and T2 w images (D). Images (E–H) demonstrated normalization of MRI alteration in the splenial region.

Figure 2

MRI performed at the onset for patient 2 showed focal high signal intensity of splenium of the corpus callosum in diffusion-weighted images (DWI) (A) and low signal in ADC map (B) in the same lesion. Axial FLAIR (C) and coronal T2 w (D) images confirmed the presence of a hyperintense splenial lesion. MRI performed one month later revealed complete resolution of the lesion and normal signal intensity of splenium of corpus callosum (E–H).