Pathology Associates of Anaheim, Anaheim, CA, USA.
Anaheim Regional Medical Center, Anaheim, CA, USA.
BMC Pulm Med. 2021 Aug 31;21(1):278. doi: 10.1186/s12890-021-01643-y.
There are various reasons for delayed positive nasopharyngeal PCR tests for coronavirus disease 2019 (COVID19) in not only asymptomatic but also severely diseased patients. The pathophysiological attributes are not known. We explore this possibility through a case report.
A 64-year-old male with history of pulmonary fungal infection, asthma and chronic pulmonary obstructive disease (COPD), diabetes, coronary artery disease presented with shortness of breath, fever and chest image of ground opacity, reticular interstitial thickening, highly suspicious for COVID19. However, nasopharyngeal swab tests were discordantly negative for four times in two weeks, and IgG antibody for COVID19 was also negative. However, serum IgE level was elevated. No other pathogens are identified. His symptoms deteriorated despite corticosteroid, antibiotics and bronchodilator treatment. Bronchoalveolar lavage (BAL) and open lung wedge biopsy were performed for etiology diagnosis. They demonstrated COVID19 viral RNA positive fibrosing organizing pneumonia with respiratory tract damage characterized by suspicious viral cytopathic effect, mixed neutrophilic, lymphoplasmacytic, histiocytic and eosinophilic inflammation and fibrosis besides expected asthma and COPD change. One week later, repeated COVID19 nasopharyngeal tests on day 40 and day 49 became positive.
Our case and literature review indicate that allergic asthma and associated high IgE level together with corticosteroid inhalation might contribute to the delayed positive nasopharyngeal swab in upper airway; COPD related chronic airways obstruction and the addition of fibrosis induced ventilator dependence and poor prognosis in COVID19 pneumonia, and should be therapeutically targeted besides antiviral therapy.
2019 年冠状病毒病（COVID-19）患者不仅在无症状时，而且在病情严重时，鼻咽 PCR 检测呈阳性的时间也会延迟，原因多种多样。其病理生理学特征尚不清楚。我们通过一个病例报告来探讨这种可能性。
一名 64 岁男性，有肺部真菌感染、哮喘和慢性阻塞性肺疾病（COPD）、糖尿病、冠心病病史，因呼吸急促、发热和胸部磨玻璃影、网状间质增厚而就诊，高度怀疑 COVID-19。然而，在两周内进行了 4 次鼻咽拭子检测，结果均为阴性，COVID-19 的 IgG 抗体也为阴性。然而，血清 IgE 水平升高。未发现其他病原体。尽管使用了皮质类固醇、抗生素和支气管扩张剂治疗，但他的症状仍在恶化。为了明确病因，进行了支气管肺泡灌洗（BAL）和开胸肺楔形活检。结果显示 COVID-19 病毒 RNA 阳性的纤维性机化性肺炎，呼吸道损伤特征为疑似病毒细胞病变效应，混合性中性粒细胞、淋巴浆细胞、组织细胞和嗜酸性粒细胞炎症和纤维化，此外还伴有预期的哮喘和 COPD 改变。一周后，在第 40 天和第 49 天重复 COVID-19 鼻咽检测结果转为阳性。
我们的病例和文献复习表明，过敏性哮喘和相关的高 IgE 水平，加上皮质类固醇吸入，可能导致上呼吸道鼻咽拭子检测呈阳性的时间延迟；COPD 相关的慢性气道阻塞和纤维化的增加导致 COVID-19 肺炎的呼吸机依赖和预后不良，除了抗病毒治疗外，还应针对这些因素进行治疗。
