Nephrology, Dialysis and Transplantation Unit, Careggi University Hospital, Florence, Italy.
Hemodial Int. 2021 Oct;25(4):E48-E52. doi: 10.1111/hdi.12958. Epub 2021 Jun 24.
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.
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.
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.
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.
考虑到透析患者在 COVID-19 大流行期间预后较差,且透析患者的 COVID-19 症状通常较轻或不存在,每个透析单位都应制定当地策略以早期识别受 COVID-19 影响的患者。然而,许多现有的 SARS-CoV-2 诊断检测显示出中等敏感性,80%左右可能是一个合理的估计。因此,拥有用于鉴别诊断的有用工具变得至关重要。在这种情况下,肺部超声(LUS)在评估 COVID-19 大流行期间血液透析患者的肺部受累方面可能具有重要作用。
我们介绍了两例 COVID-19 肺炎血液透析患者的病例,在这些病例中,LUS 在诊断过程中起了核心作用。COVID-19 肺炎的超声图像显示出典型的双侧模式,其特征是多个或融合的 B 线,伴有未累及区域、增厚且不规则的胸膜线以及罕见的胸膜下实变。LUS 在诊断 COVID-19 肺炎方面具有很高的准确性。
尽管这两名患者在临床上看起来容量正常且无发热,但他们均出现急性腹泻和 92%-93%的血氧饱和度。尽管两名患者的临床表现均较轻且不具特异性,但 LUS 引起了对 COVID-19 诊断的怀疑,这通过鼻咽 RT-PCR 的阳性结果得到证实。
在透析患者中,有许多原因会导致 LUS 评估时出现呼吸困难、发热和多个 B 线(如心力衰竭、容量超负荷、血管通路感染、间质性肺炎),但识别 COVID-19 肺炎的典型超声模式有助于鉴别诊断。LUS 在 COVID-19 大流行期间血液透析患者的筛查过程中可能具有重要作用,尤其是在 SARS-CoV-2 诊断检测之前症状较少的患者中,以及在出现疑似症状和/或已知接触但 SARS-CoV-2 诊断检测结果出乎意料地为阴性的患者中。