Reply to: "A multifaceted virus. Nonreducible and strangulated effects of COVID-19".

To the Editor:

On behalf of all coauthors and collected data contributors, we would like to thank Drs Mulita, Sotiropoulou, and Vailas from Greece for their comments on our recent publication entitled “Dramatic decrease of surgical emergencies during COVID-19 outbreak.”[1] This is a multicenter observational study including data from 18 emergency surgery units of hospitals homogenously distributed in Lombardy region, Italy. Data included emergency hospitalizations and surgical procedures performed during the first wave of the COVID-19 pandemic (March 2020), which were compared with data of March 2019. Our study confirmed that admissions in surgical departments and surgical emergencies significantly decreased in March 2020 compared with the same period of the previous year. We appreciated the letter by Mulita and colleagues; however, we would try to suggest some hypotheses explaining their results so different if compared with those of our study.

First, they collected data from February to December 2020, including not only the first wave of COVID-19 outbreak but also emergency operations performed later than the first peak of pandemic incidence. This is an important bias that has already been clearly declared in our study, in which we supposed a rebound effect of the number of surgical emergencies after this very particular period. In addition, as we stated in the part addressed to limitations of our analysis, the possible delay in the arrival of some surgical diseases in emergency departments or the onset of their complications could not be considered surprising. Therefore, when Mulita et al. supposed that some benign entities, like hernias, may access to hospitals with delayed onset of symptoms or complicated clinical presentation, because of the COVID-19 pandemic, they confirm our assumption, and this aspect has also been well investigated by other authors.[2-5]

Second, including only data about hernia operations, the results of Mulita et al. are hardly comparable to our results regarding several emergency surgical procedures (and, specifically, not hernia repair). Moreover, the authors declare that their experience comes from a Greek hospital covering a population of 1.5 million without any data about the zone-specific COVID-19 incidence. Since we have realized a multicenter study involving 18 surgical departments across the Lombardy region (which covers a population of about 10 million) with a quite homogeneous incidence of SARS-CoV-2 infection, we considered our data more reliable. What is more, given a so large population of 1.5 million, it should be interesting to investigate other surgical entities beyond hernias only.

In conclusion, the different design, populations and study periods may lead to a misinterpretation of our results compared with those of Mulita et al. We agree with the authors that COVID-19 pandemic has led to collateral damages: pragmatic solutions need to be established by health services to not compromise the care of patients suffering from other diseases.