Complement and complement regulatory proteins are upregulated in lungs of COVID-19 patients.

We explored the pathological changes and the activation of local complement system in COVID-19 pneumonia. Lung paraffin sections of COVID-19 infected patients were analyzed by HE (hematoxylin-eosin) staining. The deposition of complement C3, the deposition of C3b/iC3b/C3d and C5b-9, and the expression of complement regulatory proteins, CD59, CD46 and CD55 were detected by immunohistochemistry. In COVID-19 patients' lung tissues, fibrin exudation, mixed with erythrocyte, alveolar macrophage and shed pneumocyte are usually observed in the alveoli. The formation of an "alveolar emboli" structure may contribute to thrombosis and consolidation in lung tissue. In addition, we also found that compared to normal tissue, the lung tissues of COVID-19 patients displayed the hyper-activation of complement that is represented by extensive deposition of C3, C3b/iC3b/C3d and C5b-9, and the increased expression level of complement regulatory proteins CD55, and especially CD59 but not CD46. The thrombosis and consolidation in lung tissues may contribute to the pathogenesis of COVID-19. The increased expression of CD55 and CD59 may reflect a feedback of self-protection on the complement hyper-activation. Further, the increased C3 deposition and the strongly activated complement system in lung tissues may suggest the rationale of complement-targeted therapeutics in conquering COVID-19.

Case series of 20 pregnant women with 2019 novel coronavirus disease in Wuhan, China.

AIM: To evaluate perinatal outcomes regarding clinical presentation in pregnancy and the vertical transmission potential of COVID-19. METHODS: Clinical records, laboratory findings, and chest computed tomography (CT) scans were retrospectively reviewed from 20 pregnant patients with laboratory-confirmed COVID-19 who were admitted to Renmin Hospital of Wuhan University and The Third Hospital of Wuhan, from Jan 20 to Mar 16, 2020, including three in the first-trimester, two in the second-trimester, and 15 in the third-trimester. Evidence of vertical transmission was assessed by testing for neonatal throat swab samples. The pathological changes of COVID-19 on the placenta is evaluated by hematoxylin-eosin staining. RESULTS: The most common symptoms of the pregnant women with SARS-CoV-2 infection were fever and cough, which is comparable to the nonpregnant adults with COVID-19 infection. Nobody was transferred to intensive care unit (ICU) for treatment and there were no maternal and neonatal deaths. However, there was one case with induced abortions on first-trimester (due to pregnant woman's concerns about COVID-19), one diagnosed with ectopic pregnancy, no intrauterine fetal deaths during the study period. Delivery occurred in 15 patients in the third trimester. Their incidence of preterm birth was 20%. Three of the four preterm births were spontaneous. The average length of stay was 20.77 days. No neonatal SARS-CoV-2 infection was detected. There were two placentas found with acute chorioamnionitis, one showed normal placenta morphology. CONCLUSION: In this case series study, COVID-19 had no short-term adverse effect on pregnant women except premature birth. The vertical transmission of SARS-CoV-2 did not occur in our study.

Placental pathology of the third trimester pregnant women from COVID-19.

AIMS: To explore the clinical characteristics and placental pathological changes of pregnant women with 2019 novel coronavirus (CoV) disease (COVID-19) in the third trimester, and to assess the possibility of vertical transmission. METHODS AND RESULTS: The placenta tissues were evaluated by using immunohistochemistry for inflammatory cells and Hofbauer cells, and using severe acute respiratory syndrome (SARS) CoV-2 RNA Fluorescence In-Situ Hybridization (FISH) and SARS-CoV-2 spike protein immunofluorescence (IF) double staining. All eight placentas from the third trimester pregnancy women were studied. All patients were cured, no clinical or serological evidence pointed to vertical transmission of SARS-CoV-2. Features of maternal vascular malperfusion (MVM) such as increased syncytial knots were present in all 8 cases (8/8), and increased focal perivillous fibrin depositions were presented in 7 cases (7/8). No significate chronic histiocytic intervillositis was noted in the placenta. The number of macrophages and inflammatory cells such as T cells, B cells and plasma cells in the placental villous was not significantly increased in all cases. Moreover, all of eight cases demonstrated negative results by FISH using a SARS-CoV-2 virus RNA probe and by IF using a monoclonal antibody against SARS-CoV-2 spike protein. CONCLUSIONS: We found no evidence of vertical transmission and adverse maternal-fetal outcomes in the placentas of third trimester COVID-19 pregnancy women, which provided further information for the clinical management of those women in the third trimester. However, further studies are still needed for patients with infections in different stage of gestation, especially in first and second trimester.

No obviously adverse pregnancy complications and outcomes of the recovered pregnant women from COVID-19.

The effects of SARS-COV-2 infection on the pregnant women and their fetus growth have attracted worldwide concern. Our case study aimed to investigate the neonatal clinical outcomes of the recovered pregnant women from COVID-19 in China, expecting to provide the clinical references of urgent need for other countries. Our study recruited a total of 12 recovered pregnant women from COVID-19 prior to pregnancy termination. The maternal and neonatal clinical characteristics were recorded. Of them, the placental pathological characteristics of five participants were evaluated following the standard guidelines. Two of them chose induced labour due to being worry about the potential adverse effects of medical treatment for COVID-19 by themselves. For the others, 8 gave birth by cesarean section with certain indications and 2 by vaginal delivery. Their neonates were all live birth with ≥ 37 gestational weeks and high Apgar scores of 9 ∼ 10. For the neonate related biological samples, they all have negative results of RNA test, including nasopharyngeal swab, umbilical cord blood, amniotic fluid, vaginal fluid, placenta, or umbilical cord. Most of other pathological indicators of placental examination suggested no abnormal syndromes. Overall, we did not find any abnormal pregnancy complications and neonatal outcomes among them. We concluded that excess adverse effect on the fetus development due to COVID-19 in the recovered pregnant women should be less influential, especially, induce abortion due to the anxiety of COVID-19 treatment should be not advisable.

Postoperative Onset and Detection of SARS-CoV-2 in Surgically Resected Specimens From Gastrointestinal Cancer Patients With Pre/Asymptomatic COVID-19.

OBJECTIVE: To describe the epidemiologic features and clinical courses of gastrointestinal cancer patients with pre/asymptomatic COVID-19 and to explore evidence of SARS-CoV-2 in the surgically resected specimens. SUMMARY BACKGROUND DATA: The advisory of postponing or canceling elective surgeries escalated a worldwide debate regarding the safety and feasibility of performing elective surgical procedures during this pandemic. Limited data are available on gastrointestinal cancer patients with pre/asymptomatic COVID-19 undergoing surgery. METHODS: Clinical data were retrospectively collected and analyzed. Surgically resected specimens of the cases with confirmed COVID-19 were obtained to detect the expression of ACE2 and the presence of SARS-CoV-2. RESULTS: A total of 52 patients (male, 34) with a median age 62.5 years were enrolled. All the patients presented no respiratory symptoms or abnormalities on chest computed tomography before surgery. Six patients (11.5%) experienced symptom onset and were confirmed to be COVID-19. All were identified to be preoperatively pre/asymptomatic, as 5 were with SARS-CoV-2 presenting in cytoplasm of enterocytes or macrophages from the colorectal tissues and 1 had symptom onset immediately after surgery. The case fatality rate in patients with COVID-19 was 16.7%, much higher than those without COVID-19 (2.2%). CONCLUSIONS: Gastrointestinal cancer patients with pre/asymptomatic COVID-19 were at high risk of postoperative onset and death. At current pandemic, elective surgery should be postponed or canceled. It highlights the need for investigating the full clinical spectrum and natural history of this infection. The early colorectal tropism of SARS-CoV-2 may have major implications on prevention, diagnosis, and treatment of COVID-19.

Pulmonary pathology of early-phase COVID-19 pneumonia in a patient with a benign lung lesion.

AIMS: An ongoing outbreak of 2019 novel coronavirus (CoV) disease (COVID-19), caused by severe acute respiratory syndrome (SARS) CoV-2, has been spreading in multiple countries. One of the reasons for the rapid spread is that the virus can be transmitted from infected individuals without symptoms. Revealing the pathological features of early-phase COVID-19 pneumonia is important for understanding of its pathogenesis. The aim of this study was to explore the pulmonary pathology of early-phase COVID-19 pneumonia in a patient with a benign lung lesion. METHODS AND RESULTS: We analysed the pathological changes in lung tissue from a 55-year-old female patient with early-phase SARS-CoV-2 infection. In this case, right lower lobectomy was performed for a benign pulmonary nodule. Detailed clinical, laboratory and radiological data were also examined. This patient was confirmed to have preoperative SARS-CoV-2 infection by the use of real-time reverse transcription polymerase chain reaction and RNA in-situ hybridisation on surgically removed lung tissues. Histologically, COVID-19 pneumonia was characterised by exudative inflammation. The closer to the visceral pleura, the more severe the exudation of monocytes and lymphocytes. Perivascular inflammatory infiltration, intra-alveolar multinucleated giant cells, pneumocyte hyperplasia and intracytoplasmic viral-like inclusion bodies were seen. However, fibrinous exudate and hyaline membrane formation, which were typical pulmonary features of SARS pneumonia, were not evident in this case. Immunohistochemical staining results showed an abnormal accumulation of CD4+ helper T lymphocytes and CD163+ M2 macrophages in the lung tissue. CONCLUSION: The results highlighted the pulmonary pathological changes of early-phase SARS-CoV-2 infection, and suggested a role of immune dysfunction in the pathogenesis of COVID-19 pneumonia.

Novel Coronavirus Infection in Hospitalized Infants Under 1 Year of Age in China

Previous studies suggest that COVID-19 is more likely to infect older adult men, particularly those with chronic comorbidities.2-4 Few infections in children have been reported. We identified all infected infants in China and described demographic, epidemiologic, and clinical features.