NAFLD determined by Dallas Steatosis Index is associated with poor outcomes in COVID-19 pneumonia: a cohort study.

Coronavirus disease 2019 is a worldwide health challenge. Liver steatosis diagnosis based on imaging studies has been implicated in poor outcomes of COVID-19 pneumonia, but results are inconsistent. The Dallas Steatosis Index (DSI) is an available calculator developed to identify patients with non-alcoholic fatty liver disease (NAFLD). We hypothesized that it would be associated with in-hospital mortality, intensive care unit admission (ICU), and invasive mechanical ventilation (IMV). We conducted a retrospective cohort study on inpatients with confirmed COVID-19 pneumonia between February 26 and April 11, 2020. We computed the DSI on admission, and patients with high DSI were considered with NAFLD. We employed logistic regression to study the association between NAFLD, mortality, ICU admission, and IMV. We studied the association between liver steatosis on computed tomography (CT) and these outcomes, and also between Metabolic Associated Fatty Liver Disease (MAFLD) based on CT findings and risk factors and the outcomes. 470 patients were included; 359 had NAFLD according to the DSI. They had a higher frequency of type 2 diabetes (31% vs 14%, p < 0.001), obesity (58% vs 14%, p < 0.001), and arterial hypertension (34% vs 22%, p = 0.02). In univariable analysis, NAFLD was associated with mortality, ICU admission, and IMV. Liver steatosis by CT and MAFLD were not associated with any of these outcomes. In multivariable logistic regression, high DSI remained significantly associated with IMV and death. High DSI, which can be easily computed on admission, was associated with IMV and death, and its use to better stratify the prognosis of these patients should be explored. On the other hand, liver steatosis by CT and MAFLD were not associated with poor outcomes.

Types of Cerebral Herniation and Their Imaging Features.

Cerebral herniation, defined as a shift of cerebral tissue from its normal location into an adjacent space, is a life-threatening condition that requires prompt diagnosis. The imaging spectrum can range from subtle changes to clear displacement of brain structures. For radiologists, it is fundamental to be familiar with the different imaging findings of the various subtypes of brain herniation. Brain herniation syndromes are commonly classified on the basis of their location as intracranial and extracranial hernias. Intracranial hernias can be further divided into three types: (a) subfalcine hernia; (b) transtentorial hernia, which can be ascending or descending (lateral and central); and (c) tonsillar hernia. Brain herniation may produce brain damage, compress cranial nerves and vessels causing hemorrhage or ischemia, or obstruct the normal circulation of cerebrospinal fluid, producing hydrocephalus. Owing to its location, each type of hernia may be associated with a specific neurologic syndrome. Knowledge of the clinical manifestations ensures a focused imaging analysis. To make an accurate diagnosis, the authors suggest a six-key-point approach: comprehensive analysis of a detailed history of the patient and results of clinical examination, knowledge of anatomic landmarks, direction of mass effect, recognition of displaced structures, presence of indirect radiologic findings, and possible complications. CT and MRI are the imaging modalities of choice used for establishing a correct diagnosis and guiding therapeutic decisions. They also have important prognostic implications. The preferred imaging modality is CT: the acquisition time is shorter and it is less expensive and more widely available. Patients with brain herniation are generally in critical clinical condition. Making a prompt diagnosis is fundamental for the patient's safety.©RSNA, 2019.