The aim of this report was to present a selection of focal hyperechoic liver lesions of different etiologies, illustrating the wide spectrum of diagnostic possibilities for such lesions in the pediatric population.

Keywords: Liver/diagnostic imaging; Ultrasonography; Liver neoplasms/diagnosis; Diagnosis, differential; Infant; Child; Adolescent.

In the current pandemic, caused by infection with severe acute respiratory syndrome coronavirus 2, ultrasound has played a fundamental role in patients who develop the resulting disease, designated coronavirus disease 2019 (COVID-19). In this study we present ultrasound images of the lungs of neonates with a suspected or confirmed diagnosis of COVID-19, distinguishing between the changes related to COVID-19 and those unrelated to the disease. Ultrasound examinations were performed by a pediatric sonographer. A total of 27 neonates were evaluated. Among those who presented no respiratory symptoms, some tested negative for COVID-19 and others tested positive. All of those who were pulmonary symptomatic, negative for COVID-19 presented transient tachypnea of the newborn and respiratory distress syndrome. Lung ultrasound images obtained in COVID-19-negative neonates showed, in some cases, a normal pattern (with A lines, few B lines, a thin, linear pleural line, and no pleural effusion), whereas in others showed coalescent B lines and areas of opacity. In two of the COVID-19-positive neonates, lung ultrasound examination showed several coalescent B lines, pleural thickening, and areas of opacity. Lung ultrasound in the neonatal period appears to be applicable within the context of the current pandemic, allowing efficient evaluation of COVID-19-related changes in neonates, as well as of pathologies inherent to the neonatal period.

Keywords: Ultrasonography; Lung/diagnostic imaging; Coronavirus infections/diagnostic imaging; Coronavirus; Infant, newborn.

Although contrast-enhanced ultrasound has been shown to provide considerable benefits, particularly in pediatric patients, it is still used relatively rarely in Brazil. It has proven to be a safe technique, and adverse effects are rare. In this review, we address the technique and main applications of contrast-enhanced ultrasound in the pediatric population, including the evaluation of focal liver lesions, abdominal trauma, kidney grafts, liver grafts, bowel loops, and vesicoureteral reflux. It is important for pediatric radiologists to be acquainted with this promising tool, understanding its applications and limitations.

Keywords: Pediatrics; Ultrasonography; Contrast media; Microbubbles.

OBJECTIVE: To describe the radiological findings in pediatric patients with hematological or oncological diseases who also have an invasive fungal infection (IFI). MATERIALS AND METHODS: This was a retrospective study of all patients with IFI admitted to a pediatric hematology and oncology hospital in Brazil between 2008 and 2014. Clinical and demographic data were collected. Chest computed tomography (CT) scans of the patients were reviewed by two independent radiologists. RESULTS: We evaluated the chest CT scans of 40 pediatric patients diagnosed with an IFI. Twenty-seven patients (67.5%) had nodules with the halo sign, seven (17.5%) had cavities, two (5.0%) had nodules without the halo sign, and seven (17.5%) had consolidation. The patients with the halo sign and cavities were older (123 vs. 77 months of age; p = 0.03) and had less severe disease (34% vs. 73%; p = 0.04). Ten patients had a proven IFI: with Aspergillus sp. (n = 4); with Candida sp. (n = 5); or with Fusarium sp. (n = 1). CONCLUSION: A diagnosis of IFI should be considered in children and adolescents with risk factors and abnormal CT scans, even if the imaging findings are nonspecific.

Keywords: Mycoses/diagnostic imaging; Child; Adolescent; Immunocompromised host; Tomography, X-ray computed.