key: cord-0705656-hyvyp1rx
authors: Yassa, Murat; Tug, Niyazi
title: Reply
date: 2020-08-27
journal: J Ultrasound Med
DOI: 10.1002/jum.15457
sha: 001bca3d95d439235417a16d5a30e3a9ba9a5c72
doc_id: 705656
cord_uid: hyvyp1rx

nan

To the Editor: We thank Youssef and colleagues for their interest in our article and for taking the time to express their concerns about the usefulness of LUS as a screening tool for SARS-CoV-2 in pregnant women. The authors briefly shared their findings from a small screening program that resulted in their position against the role of LUS in screening pregnant women for SARS-CoV-2 infection. As a response, we would like to highlight some important nuances that are worthy of discussion.

Our case series consecutively included 7 pregnant women infected with COVID-19 pneumonia and 1 didactic noninfected case. 1 All patients were symptomatic, and identifying their lung involvement has influenced the treatment of all pregnant women with COVID-19 pneumonia. On the contrary, Youssef and colleagues performed LUS examinations only on asymptomatic pregnant women. Although their inclusion criteria are not known, it is clear that the two cohorts targeted different populations. It should also be noted that the prevalence of positive test results for SARS-CoV-2 either by RT-PCR or LUS might be affected by a small population size, community transmission rates, the testing period, and the intensity of the pandemic for a specific time and location. 2 We also tested the universal screening program in May 2020 using both PCR testing and LUS on 296 pregnant women regardless of the week of gestation who were admitted to the obstetric unit for any indication. 3 The rates of asymptomatic and symptomatic pregnant women with a diagnosis of SARS-CoV-2 were 4% and 3.7%, respectively. In addition, 17.4% of the patients with positive test results for SARS-CoV-2 were initially found to be PCR negative, underwent repeated testing in a week because of their abnormal LUS findings, and eventually had positive PCR results.

We agree with Youssef and colleagues that LUS is likely to be more useful in symptomatic patients. Indeed, LUS is an effective and accurate imaging tool particularly for patients with a specific background for COVID-19 pneumonia. Thus, we proposed an algorithm to be used for the interpretation of LUS findings in universal screening programs while waiting for PCR test results. 3 A standardized LUS scoring system was used in this algorithm. 4 Briefly, an LUS score of 1 was adopted as a normal finding in asymptomatic pregnant women. Lung ultrasound scores of 2 and 3 were adopted as abnormal regardless of the symptom status. This strategy showed a positive predictive value of 82.3% (95% confidence interval, 59.1%-93.78%) in detecting COVID-19 pneumonia. 3 We believe that this strategy has the potential to reduce the need for chest computed tomography in pregnant women during the pandemic.

Currently, a universal screening program is not in effect in our center, and we routinely perform LUS examinations only on pregnant women suspected or having a diagnosis of COVID-19 pneumonia. Although universal screening seems not to be an essential policy at the present time, testing all pregnant women admitted to the hospital may be necessary in a future second wave or in other pandemics. Thus, screening with LUS for COVID-19 pneumonia in pregnant women under the proposed scenario may be useful, particularly in low-resource settings that do not have enough access to liberal use of fast PCR testing and where a standard ultrasound scan for a fetal assessment is available.

Lung ultrasound is an effective imaging tool for obstetricians to diagnose lung involvement in COVID-19. 5 Considering that a LUS examination has a nonionizing nature, is rapid to perform, and is easy to interpret, 6 we believe that obstetricians should liberally benefit from the advantages of LUS for pregnant women either in universal screening programs or as a part of the routine clinical evaluation of pregnant women suspected or having a diagnosis of SARS-CoV-2 infection.

Lung ultrasound can influence the clinical treatment of pregnant women with COVID-19

Severe acute respiratory syndrome coronavirus 2 in pregnancy: symptomatic pregnant women are only the tip of the iceberg

Outcomes of universal SARS-CoV-2 testing program in pregnant women admitted to hospital and the adjuvant role of lung ultrasound in screening: a prospective cohort study

Proposal for international standardization of the use of lung ultrasound for patients with COVID-19: a simple, quantitative, reproducible method

Lung ultrasound in pregnant women during the COVID-19 pandemic: an interobserver agreement study among obstetricians

How to perform lung ultrasound in pregnant women with suspected COVID-19