Lung ultrasound may help in the differential diagnosis of suspected oligosymptomatic COVID-19 patients on hemodialysis: A case report.

INTRODUCTION: Considering that patients on dialysis showed a poor outcome during COVID-19 pandemic, and that COVID-19 symptoms in dialysis patients are often mild or absent, each dialysis unit should implement local strategies to early recognize patients affected by COVID-19. However, many available SARS-CoV-2 diagnostic tests demonstrated a moderate sensitivity, 70%-80% is probably a reasonable estimate. Consequently, having useful tools for differential diagnosis becomes essential. In this scenario, lung ultrasound (LUS) may have an important role in the evaluation of lung involvement in hemodialysis patients during COVID-19 pandemic. METHODS: We present two cases of hemodialysis patients with COVID-19 pneumonia in whom LUS had a central role in the diagnostic process. Ultrasound images of COVID-19 pneumonia show a typical bilateral pattern characterized by multiple or confluent B-lines with spared areas, thickened and irregular pleural line, and rare subpleural consolidations. LUS showed high accuracy in diagnosing COVID-19 pneumonia. FINDINGS: Despite both patients appeared clinically euvolemic and afebrile, they presented with acute diarrhea and oxygen saturation level of 92%-93%. Although clinical manifestations were mild and not specific in both patients, LUS raised suspicion on the possible COVID-19 diagnosis which was confirmed by a positive nasopharyngeal RT-PCR. DISCUSSION: There are many reasons for a patient on dialysis to present shortness of breath, fever, and multiple B-lines at LUS assessment (such as heart failure, fluid overload, vascular access infection, interstitial pneumonia) but the recognition of typical ultrasound patterns of the COVID-19 pneumonia is helpful for differential diagnosis. LUS may have an important role in the screening process of hemodialysis patients during the COVID-19 pandemic, especially in oligosymptomatic patients before the SARS-CoV-2 diagnostic tests, and in those with suspected symptoms and/or known exposure with unexpected negative SARS-CoV-2 diagnostic tests.

Lung Ultrasound May Support Diagnosis and Monitoring of COVID-19 Pneumonia.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) disease (COVID-19) is characterized by severe pneumonia and/or acute respiratory distress syndrome in about 20% of infected patients. Computed tomography (CT) is the routine imaging technique for diagnosis and monitoring of COVID-19 pneumonia. Chest CT has high sensitivity for diagnosis of COVID-19, but is not universally available, requires an infected or unstable patient to be moved to the radiology unit with potential exposure of several people, necessitates proper sanification of the CT room after use and is underutilized in children and pregnant women because of concerns over radiation exposure. The increasing frequency of confirmed COVID-19 cases is striking, and new sensitive diagnostic tools are needed to guide clinical practice. Lung ultrasound (LUS) is an emerging non-invasive bedside technique that is used to diagnose interstitial lung syndrome through evaluation and quantitation of the number of B-lines, pleural irregularities and nodules or consolidations. In patients with COVID-19 pneumonia, LUS reveals a typical pattern of diffuse interstitial lung syndrome, characterized by multiple or confluent bilateral B-lines with spared areas, thickening of the pleural line with pleural line irregularity and peripheral consolidations. LUS has been found to be a promising tool for the diagnosis of COVID-19 pneumonia, and LUS findings correlate fairly with those of chest CT scan. Compared with CT, LUS has several other advantages, such as lack of exposure to radiation, bedside repeatability during follow-up, low cost and easier application in low-resource settings. Consequently, LUS may decrease utilization of conventional diagnostic imaging resources (CT scan and chest X-ray). LUS may help in early diagnosis, therapeutic decisions and follow-up monitoring of COVID-19 pneumonia, particularly in the critical care setting and in pregnant women, children and patients in areas with high rates of community transmission.