[Pregnancy with new coronavirus infection: clinical characteristics and placental pathological analysis of three cases].

Objective: To investigate the clinical characteristics and placental pathology of 2019-nCoV infection in pregnancy,and to evaluate intrauterine vertical transmission potential of 2019-nCoV infection. Methods: The placentas delivered from pregnant women with confirmed 2019-nCoV infection which were received in the Department of Pathology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology by February 4, 2020 were retrospectively studied. Their clinical material including placental tissue and lung CT, and laboratory results were collected, meanwhile, nucleic acid detection of 2019-nCoV of the placentas were performed by RT-PCR. Results: Three placentas delivered from pregnant women with confirmed 2019-nCoV infection, who were all in their third trimester with emergency caesarean section. All of the three patients presented with fever (one before caesarean and two in postpartum), and had no significant leukopenia and lymphopenia. Neonatal throat swabs from three newborns were tested for 2019-nCoV, and all samples were negative for the nucleic acid of 2019-nCoV. One premature infant was transferred to Department of Neonatology due to low birth weight. By the end of February 25, 2020, none of the three patients developed severe 2019-nCoV pneumonia or died(two patients had been cured and discharged, while another one had been transferred to a square cabin hospital for isolation treatment). There were various degrees of fibrin deposition inside and around the villi with local syncytial nodule increases in all three placentas. One case of placenta showed the concomitant morphology of chorionic hemangioma and another one with massive placental infarction. No pathological change of villitis and chorioamnionitis was observed in our observation of three cases. All samples from three placentas were negative for the nucleic acid of 2019-nCoV. Conclusions: The clinical characteristics of pregnant women with 2019-nCoV infection in late pregnancy are similar to those of non-pregnant patients, and no severe adverse pregnancy outcome is found in the 3 cases of our observation. Pathological study suggests that there are no morphological changes related to infection in the three placentas. Currently no evidence for intrauterine vertical transmission of 2019-nCoV is found in the three women infected by 2019-nCoV in their late pregnancy.

[Pathological changes of the spleen in ten patients with coronavirus disease 2019(COVID-19) by postmortem needle autopsy].

Objective: To study the pathological changes of the spleen in patients with COVID-19 and to analyze the relationship between the weakened immune system and splenic lesions. Methods: Postmortem needle autopsies from the spleen were carried out on 10 patients who died from COVID-19 in Wuhan. Routine hematoxylin and eosin (HE) staining was used to observe the pathological changes. The changes of lymphocytes were studied further with immunohistochemistry.RT-PCR was used to detect 2019-nCoV RNA in the spleen. In addition,the Epstein-Barr virus (EBV) was detected by in situ hybridization, and coronavirus particles were detected by transmission electron microscopy in 2 cases. Results: There were 7 males and 3 females, with an average age of 68.3 years.Of the 10 cases, 4 had cancer history and another 4 had other underlying diseases respectively.Cough, fever, malaise and dyspnea were the main clinical symptoms.The time from onset to death was 15-45 days.Ten cases patients had normal or slight increase in peripheral blood leukocyte count in the early stage of the disease, 6 cases had significant increase before death. Five patients' peripheral blood lymphocyte count decreased in the early stage of the disease, and 10 patients' peripheral blood lymphocyte count decreased significantly before the disease progressed or died. Seven cases were treated with corticosteroid (methylprednisolone ≤40 mg/d, not more than 5 days). Histopathological examination showed that the cell composition of the spleen decreased, white pulp atrophied at different levels, meanwhile lymphoid follicles decreased or absent;in addition, the ratio of red pulp to white pulp increased with varying degrees. In 7 cases, more neutrophil infiltration was found, and in 5 cases, scattered plasma cell infiltration was found. Macrophage proliferation and hemophagocytic phenomena in a few cells were found in a case. Meanwhile, necrosis and lymphocyte apoptosis were detected in 2 cases, small artery thrombosis and spleen infarction in 1 case, and fungal infection in 1 case. The results of immunohistochemistry showed that the T and B lymphocyte components of the spleen in all cases decreased in varying degrees. CD20(+) B cells were found to accumulate in the lymphoid sheath around the splenic artery in 8 cases. However, CD20 and CD21 immunostaining in 2 cases showed that the number of white pulp was almost normal, and splenic nodules were atrophic. CD3(+), CD4(+) and CD8(+)T cells were decreased. In 9 cases,CD68(+) macrophages were no significant changes in the distribution and quantity. While more CD68(+) cells were found in the medullary sinuses of 1 case (related to fungal infection). Few CD56(+) cells were found. EBV was negative by in situ hybridization. RT-PCR was used to detect the nucleic acid of 2019-nCoV. One of 10 cases was positive, 39 years old,who was the youngest patient in this group, and the other 9 cases were negative. Coronavirus particles were found in the cytoplasm of macrophage under electron microscope in 2 cases. Conclusions: The death of COVID-19 occurs mainly in the elderly, and some cases have no underlying diseases. Spleen may be one of the organs directly attacked by the virus in some patients who died from COVID-19. T and B lymphocyte in the spleen decrease in varying degrees, lymphoid follicles are atrophied, decreased or absent, and the number of NK cells do not change significantly. And the pathological changes of the spleen are not related to the use of low dose corticosteroid, which may be related to the direct attack of virus and the attack of immune system on its own tissues.

[Pathological changes of fatal coronavirus disease 2019 (COVID-19) in the lungs: report of 10 cases by postmortem needle autopsy].

Objectives: To observe the pulmonary changes with coronavirus disease 2019 (COVID-19) in postmortem needle specimens, to detect the presence of 2019 novel coronavirus(2019-nCoV) in the lung tissues, and to analyze the clinicopathological characteristics. Methods: For 10 decedents with 2019-nCoV infection in Wuhan, bilateral lungs underwent ultrasound-guided percutaneous multi-point puncture autopsy, and pulmonary pathological changes were described in routine hematoxylin-eosin staining (HE) slides. Electron microscopy was also performed. The reverse transcription polymerase chain reaction (RT-PCR) was employed to detect 2019-nCoV nucleic acid in lung tissue, and the pathological characteristics were demonstrated in combination with clinical data analysis. Results: Of the 10 deaths associated with COVID-19, 7 were male and 3 were female. The average age was 70 (39-87) years. Medical record showed that 7 patients had underlying diseases. The average course of disease was 30 (16-36) days. Nine cases showed fibrinous and suppurative exudation in the alveolar cavity accompanied by the formation of hyaline membrane, and fibroblastic proliferation of alveolar septum. Type Ⅱ alveolar epithelial cells showed reactive hyperplasia and desquamation. Many macrophages accumulated in the alveolar cavity. Capillary hyaline thrombus and intravascular mixed thrombus were noted. In some cases, acute bronchiolitis with mucous membrane exfoliation, accumulation of bronchiolar secretions, and bronchiolar epithelial metaplasia occurred. In the cohort, a large number of bacteria (cocci) were detected in 1 case and a large number of fungi (yeast type) were detected in 1 case. Nine cases were positive for the nucleic acids of 2019-nCoV while one case remained negative by RT-PCR. Coronavirus particles were detected in the cytoplasm of type Ⅱ alveolar epithelium. Conclusions: The pulmonary pathological changes of fatal COVID-19 are diffuse alveolar damage (DAD), mainly in the acute exudative stage and the organic proliferative stage. There are fibrinous exudate aggregation in alveolar cavity with hyaline membrane formation, fibroblastic proliferation in alveolar septum, and alveolar epithelial cell injuries with reactive hyperplasia and desquamation of type Ⅱ alveolar epithelial cells. A large amount of neutrophils and monocytes infiltration is present in most cases and bacteria and fungi are detected in some cases, suggesting a serious bacterial or fungal infection secondary to the DAD.