Critical Illness-associated Cerebral Microbleeds Research Articles

Critical illness-associated cerebral microbleeds.

Critical illness-associated cerebral microbleeds.

Letter to the editor regarding differentiating fat embolism from critical illness-associated cerebral microbleeds

•Fat embolism syndrome a complication of vaso-occlusive crisis in sickle cell disease •Critical illness associated cerebral microbleeds are rarely seen in patients after prolonged respiratory distress •Microhemorrhage of the deep white matter, basal ganglia, and thalami with diffusion restriction suggests fat embolism •Exchange transfusion improves mortality for fat embolism syndrome and sickle cell disease

Critical illness-associated brain microhemorrhages in a child with multisystem inflammatory syndrome secondary to coronavirus disease 2019

A previously healthy 7-year-old male presented with fever, vomiting, and cutaneous rash for 5 days. The nasal swab reverse-transcription polymerase chain reaction for severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) was positive. After 4 days, the patient became hypoxic, with an oxygen saturation of 85%. The patient was intubated and admitted to the intensive care unit (ICU). A hemogram revealed leucopenia and low platelet count of 120,000 cells/mm3; however, normal prothrombin and partial thromboplastin time were observed. The patient did not experience hypotension, hypertension, and autonomic dysfunction. The patient was extubated on day 10 after ICU admission. Due to the suspicion of multisystem inflammatory syndrome associated with coronavirus disease 2019 (COVID-19), a coronary computed tomography angiography was performed, revealing coronary arteries ectasia. Three days after extubation, a brain magnetic resonance imaging (MRI) was performed due to confusion and dizziness, which showed microhemorrhages in the splenium of the corpus callosum, as seen on susceptibility-weighted imaging (SWI) (Fig. 1). Critical illness-associated cerebral microhemorrhages have been reported in patients with high altitude cerebral edema, acute respiratory failure, or severe asthma, usually in the corpus callosum (often the splenium), juxtacortical, and periventricular white matter.1Gupta N.A. Lien C. Iv M. Critical illness-associated cerebral microbleeds in severe COVID-19 infection.Clin Imaging. 2020; 68: 239-241Abstract Full Text Full Text PDF PubMed Scopus (7) Google Scholar Previous studies showed that critically ill patients with acute respiratory distress syndrome, who were treated with mechanical ventilation, also presented cerebral microhemorrhages.2Fitsiori A. Pugin D. Thieffry C. Lalive P. Vargas M.I. COVID-19 is associated with an unusual pattern of brain microbleeds in critically ill patients.J Neuroimaging. 2020; 30: 593-597Crossref PubMed Scopus (60) Google Scholar Hypoxia, secondary to acute respiratory failure, can lead to hydrostatic or chemical-related blood–brain barrier disruption and consequent red blood cells extravasation unrelated to diffuse intravascular coagulation. Patients with severe COVID-19 associated with acute respiratory distress syndrome can also present this complication. Evidence that SARS-CoV-2 can enter endothelial cells and cause endothelial damage has been reported; however, blood–brain barrier dysfunction secondary to hypoxemia is the main mechanism leading to cerebral microhemorrhages in patients with severe COVID-19,3Lersy F. Willaume T. Brisset J.C. Collange O. Helms J. Schneider F. et al.Critical illness-associated cerebral microbleeds for patients with severe COVID-19: etiologic hypotheses.J Neurol. 2020; https://doi.org/10.1007/s00415-020-10313-8Crossref PubMed Scopus (19) Google Scholar including multisystem inflammatory syndrome in children and adolescents.4Jiang L. Tang K. Levin M. Irfan O. Morris S.K. Wilson K. et al.COVID-19 and multisystem inflammatory syndrome in children and adolescents.Lancet Infect Dis. 2020; 20: e276-e288Abstract Full Text Full Text PDF PubMed Scopus (420) Google Scholar The time of occurrence of the brain microhemorrhages is difficult to estimate; however, they could probably occur at the moment of greatest hypoxia since this is the main pathophysiological mechanism. T2∗-weighted imaging and SWI are the best MRI sequences to detect these abnormalities, which are usually not seen in other sequences. DG Corrêa: image preparation and drafting of the manuscript; revision of the manuscript. LC Hygino da Cruz Jr: interpretation of data; revision of the manuscript and oversight. All authors have read and approved the final manuscript. The authors declare that they have no competing interest.

Spectrum of neuroimaging findings in COVID-19.

An outbreak of corona virus disease 2019 (COVID-19) began in China in December 2019, and rapidly spread to become a worldwide pandemic. Neurological complications encountered in hospitalized patients include acute arterial ischemic cerebrovascular stroke, cerebral venous thrombosis, critical illness-associated cerebral microbleeds, hypertensive hemorrhagic posterior reversible encephalopathy, meningoencephalitis/flare up of infections, flare up of multiple sclerosis, acute disseminated encephalomyelitis, cerebral hemodynamic/hypoxic changes such as watershed ischemic changes and hypoxic ischemic encephalopathy, and spine manifestations of Guillain Barre syndrome and viral myelitis. The purpose of our study is to illustrate the different neuroimaging features in critically ill hospitalized COVID-19 positive patients in the State of Qatar.

Critical illness-associated cerebral microbleeds for patients with severe COVID-19: etiologic hypotheses.

Background and purposeDuring the COVID-19 outbreak, the presence of extensive white matter microhemorrhages was detected by brain MRIs. The goal of this study was to investigate the origin of this atypical hemorrhagic complication.MethodsBetween March 17 and May 18, 2020, 80 patients with severe COVID-19 infections were admitted for acute respiratory distress syndrome to intensive care units at the University Hospitals of Strasbourg for whom a brain MRI for neurologic manifestations was performed. 19 patients (24%) with diffuse microhemorrhages were compared to 18 control patients with COVID-19 and normal brain MRI.ResultsThe first hypothesis was hypoxemia. The latter seemed very likely since respiratory failure was longer and more pronounced in patients with microhemorrhages (prolonged endotracheal intubation (p = 0.0002), higher FiO2 (p = 0.03), increased use of extracorporeal membrane oxygenation (p = 0.04)). A relevant hypothesis, the role of microangiopathy, was also considered, since patients with microhemorrhages presented a higher increase of the D-Dimers (p = 0.01) and a tendency to more frequent thrombotic events (p = 0.12). Another hypothesis tested was the role of kidney failure, which was more severe in the group with diffuse microhemorrhages (higher creatinine level [median of 293 µmol/L versus 112 µmol/L, p = 0.04] and more dialysis were introduced in this group during ICU stay [12 versus 5 patients, p = 0.04]).ConclusionsBlood–brain barrier dysfunction secondary to hypoxemia and high concentration of uremic toxins seems to be the main mechanism leading to critical illness-associated cerebral microbleeds, and this complication remains to be frequently described in severe COVID-19 patients.