SARS-CoV-2 in pregnancy: characteristics and outcomes of hospitalized and non-hospitalized women due to COVID-19.

BACKGROUND: There is little evidence about how novel coronavirus (SARS-CoV-2) affects pregnant women and their newborns. Comparisons with other members of the coronavirus family responsible for severe acute respiratory syndrome (SARS) have been done to predict maternal and neonatal outcomes; however, more information is required to establish clinical patterns, disease evolution and pregnancy prognosis in this group of patients. METHODS: This paper is reporting a series of 91 women diagnosed with SARS-CoV-2 infection during pregnancy and puerperium. The analysis showed that 40 patients developed pneumonia, bilateral in most cases, with a 46.2% rate of hospitalization and 4 patients requiring intensive care unit (ICU) admission. In confront with previous publications, we have found a higher rate of coronavirus disease (COVID-19) severe forms, even when compared to non-pregnant women with the same baseline characteristics. We have analyzed the demographic characteristics, pregnancy-related conditions and presenting symptoms to identify features that could determine which patients will need hospitalization because of COVID-19 (Group 1-G1) and those who not (Group 2-G2). We have found that obesity and Latin-American origin behave as risk factors: OR: 4.3; 95% CI: 1.4-13.2, and OR: 2.6; 95% CI: 1.1 - 6.2, respectively. Among the 23 patients that delivered with active SARS-CoV-2, the overall rate of cesarean section (CS) and preterm birth were 52.2% and 34.8%, respectively, but we observed that the rate of CS was even higher in G1 compared to G2: 81.8% versus 25%, p = .012. However, prematurity was equally distributed in both groups and only one preterm delivery was determined by poor maternal condition. There were no deaths among the patients neither their newborns. CONCLUSION: In conclusion, the results of our cohort reveal that SARSC-CoV-2 infection may not behave as mild as suggested during pregnancy, especially when factors as obesity or Latin-American origin are present. No evidence of late vertical transmission was noticed but prematurity and high CS rate were common findings, although it is difficult to establish any causality between these conditions and COVID-19. Further evidence is required to establish if pregnancy itself can lead to severe forms of COVID-19 disease and whether risk factors for the general population are applicable to obstetric patients. Until larger studies are available, pregnant women should be monitored carefully to anticipate severe complications.

The highly packed and dehydrated structure of preformed unexposed human pulmonary surfactant isolated from amniotic fluid.

By coating the alveolar air-liquid interface, lung surfactant overwhelms surface tension forces that, otherwise, would hinder the lifetime effort of breathing. Years of research have provided a picture of how highly hydrophobic and specialized proteins in surfactant promote rapid and efficient formation of phospholipid-based complex three-dimensional films at the respiratory surface, highly stable under the demanding breathing mechanics. However, recent evidence suggests that the structure and performance of surfactant typically isolated from bronchoalveolar lung lavages may be far from that of nascent, still unused, surfactant as freshly secreted by type II pneumocytes into the alveolar airspaces. In the present work, we report the isolation of lung surfactant from human amniotic fluid (amniotic fluid surfactant, AFS) and a detailed description of its composition, structure, and surface activity in comparison to a natural surfactant (NS) purified from porcine bronchoalveolar lavages. We observe that the lipid/protein complexes in AFS exhibit a substantially higher lipid packing and dehydration than in NS. AFS shows melting transitions at higher temperatures than NS and a conspicuous presence of nonlamellar phases. The surface activity of AFS is not only comparable with that of NS under physiologically meaningful conditions but displays significantly higher resistance to inhibition by serum or meconium, agents that inactivate surfactant in the context of severe respiratory pathologies. We propose that AFS may be the optimal model to study the molecular mechanisms sustaining pulmonary surfactant performance in health and disease, and the reference material to develop improved therapeutic surfactant preparations to treat yet unresolved respiratory pathologies.

Seroprevalence analysis of SARS-CoV-2 in pregnant women along the first pandemic outbreak and perinatal outcome.

OBJECTIVES: To evaluate the progression of the seroprevalence of SARS-CoV-2 in the pregnant population of the south of Madrid during the first wave of the COVID-19 pandemic. Secondarily we aimed to evaluate maternal and perinatal outcomes. STUDY DESIGN: Retrospective cohort study conducted at Hospital Universitario 12 de Octubre during weeks 10 to 19 of 2020, coinciding with the Spanish lockdown. We tested 769 serum samples obtained from routine serological testing during the first and third trimesters of pregnancy for specific IgG anti SARS-CoV-2 RBD and S proteins. RT-PCR tests were performed in suspected cases according to clinical practice. We compared maternal and perinatal outcomes in those with delivered pregnancies (n = 578) according to the presence or absence of specific IgG antibodies. Those with positive IgG were subdivided by the presence or absence of Covid-19 related symptoms at any time and the results of RT-PCR testing if performed. Therefore, we had 4 study groups: G1 (IgG negative), G2 (IgG positive, asymptomatic, RT-PCR testing negative or not done), G3 (IgG positive, symptomatic, RT-PCR testing negative or not done), and G4 (IgG positive, symptomatic, RT-PCR positive). RESULTS: Seropositivity increased from 0% to 21.4% (95% CI 11.8-31.0) during the study period, of which 27.9% had an asymptomatic course. Overall outcomes were favorable with a significant increased rate of preterm birth in G4 vs G1 (21.4% vs 6.7%) and cesarean/operative delivery (50% vs 26.9%). Asymptomatic and mild cases did not have differences regarding pregnancy course when compared to seronegative women. There were no documented cases of vertical or horizontal transmission. CONCLUSION: Seroprevalence in pregnant women in southern Madrid went up to 21.4% of which 27.9% had an asymptomatic course. Overall perinatal results were favorable, especially in those asymptomatic.

Incidence and clinical profiles of COVID-19 pneumonia in pregnant women: A single-centre cohort study from Spain.

BACKGROUND: Information regarding the incidence and characteristics of COVID-19 pneumonia amongst pregnant women is scarce. METHODS: Single-centre experience with 32 pregnant women diagnosed with COVID-19 between March 5 to April 5, 2020 at Madrid, Spain. FINDINGS: COVID-19 pneumonia was diagnosed in 61·5% (32/52) women. Only 18·7% (6/32) had some underlying condition (mostly asthma). Supplemental oxygen therapy was required in 18 patients (56·3%), with high-flow requirements in six (18·7%). Eight patients (25·0%) fulfilled the criteria for acute distress respiratory syndrome. Invasive mechanical ventilation was required in two patients (6·2%). Tocilizumab was administered in five patients (15·6%). Delivery was precipitated due to COVID-19 in three women (9·4%). All the newborns had a favourable outcome, with no cases of neonatal SARS-CoV-2 transmission. Severe cases of pneumonia requiring supplemental oxygen were more likely to exhibit bilateral alveolar or interstitial infiltrates on chest X-ray (55·6% vs. 0·0%; P-value = 0·003) and serum C-reactive protein (CRP) levels >10 mg/dL (33·0% vs. 0·0%; P-value = 0·05) at admission than those with no oxygen requirements. INTERPRETATION: Pregnant women with COVID-19 have a high risk of developing pneumonia, with a severe course in more than half of cases. The presence of bilateral kung infiltrates and elevated serum CRP at admission may identify women at-risk of severe COVID-19 pneumonia. FUNDING: Instituto de Salud Carlos III (COV20/00,181), Spanish Ministry of Science and Innovation.

Structure and activity of human surfactant protein D from different natural sources.

Surfactant protein D (SP-D) is a C-type lectin that participates in the innate immune defense of lungs. It binds pathogens through its carbohydrate recognition domain in a calcium-dependent manner. Human surfactant protein D (hSP-D) has been routinely obtained from bronchoalveolar lavage of patients suffering from pulmonary alveolar proteinosis (PAP) and from amniotic fluid (AF). As a consequence of the disease, hSP-D obtained from PAP is found in higher amounts and is mainly composed of higher order oligomeric forms. However, PAP-hSP-D has never been directly compared with nonpathological human protein in terms of structure and biological activity. Moreover, the quantitative distribution of the different hSP-D oligomeric forms in human protein obtained from a natural source has never been evaluated. In this work, we have determined the quantitative distribution of AF-hSP-D oligomers, characterized the sugars attached through the N-glycosylation site of the protein, and compared the activity of hSP-D from AF and PAP with respect to their ability to bind and agglutinate bacteria. We have found that fuzzy balls (40%) are the most abundant oligomeric form in AF-hSP-D, very closely followed by dodecamers (33%), with both together constituting 73% of the protein mass. The glycan attached to the N-glycosylation site was found to be composed of fucose, galactose, sialic acid, and N-acetylglucosamine. Finally, in the functional assays performed, hSP-D obtained from PAP showed higher potency, probably as a consequence of its higher proportion of large oligomers compared with hSP-D from AF.