Impact of COVID-19 on the number of transplants performed in Brazil during the pandemic. Current situation

ABSTRACT The intense use of resources to combat COVID-19 causes concern in the entire transplant community because, in addition to physical limitations such as ICU beds, lack of homogeneous treatment protocols and uncertainties about the effects of immunosuppression on viral progression have significant impact on transplant surgeries. The aim of the present study is to comparatively assess the number of solid organ transplants performed in 2019 and 2020, as well as the impact of the COVID-19 pandemic on organ donation and transplant surgeries in Brazil. The last 10 years have shown increasing trend in the number of solid organ transplants, which have significantly decreased in 2020. Lung transplantations were mostly affected by the pandemic; these surgeries have been carried out only in Rio Grande do Sul and São Paulo states. Liver transplantations were the least affected ones, since the number of surgeries have only decreased by 10.8% in the first three quarters of 2020, in comparison to 2019. The number of active patients on the waiting list for heart and kidney transplantation has increased in 2020. Therefore, it is necessary developing strategies to keep the structure necessary for organ transplantation processes active and, consequently, to reduce the impacts of the pandemic on these patients.


INTRODUCTION
T he Coronaviridae family is globally known and presents high mutation ability 1  the causative agent was identified as a single-stranded β-coronavirus, subsequently categorized as Sars-CoV-2 (Acute Respiratory Distress Syndrome), which presents higher infectivity than the previous virus 2, 3 .
The virus relates to the human body through the S protein (spike protein), which binds to the angiotensinconverting enzyme 2 (ACE2). The latter is widely expressed in human tissues, mainly those of the lower respiratory tract (in particular, in type II pneumocytes) 4 . Disease signs and symptoms -such as fever, tiredness/fatigue, dry cough, lack of appetite/anorexia, muscle pain, dyspnea, sore throat, runny nose, headache, nausea and diarrhea -tend to appear after the incubation time, which ranges from two to 14 days (five days, on average). Disease progression to respiratory failure is likely to happen in extreme cases, mainly in elderly individuals and/or in patients who have some comorbidity. It is essential to provide support to these patients in intensive care units (ICUs), where mechanical ventilation can be used as a life support resource 2,3 .
The complexity of cases has worldwide overwhelmed the public health systems 5   The current pandemic has significant impact on transplant procedures 7,10 . A study carried out in the Netherlands has shown a decrease in the number of transplants by 67% in the first month of the pandemic, which, for example, increased the mortality rate among patients waiting for kidney transplantation 11 .
The aim of the present study was to comparatively assess the number of transplant operations performed in 2019 and 2020, as well as the impact of the COVID-19 pandemic on organ donation, in Brazil.

RESULT
Transplant operations included in the current study comprised solid organs such as heart, lung, liver, pancreas and kidney, from January to September 2019 and 2020 9,12 ( Table 1).
The state analysis has shown that the number of potential and effective donors in the country ranged from 8,469 potential donors and 2,775 effective donors in 2019 to 7,725 potential donors and 2,438 effective donors in 2020 9,12 ( Table 2). In 2020, there was a decrease in the number of donors whose organs were transplanted 9,12 (Table 3). There was an increasing trend in the number of transplants of most solid organs in the last 10 years; however, this number was significantly decreased in 2020 (Table 4). This phenomenon can be easily visualized in Graphic 1, which was plotted by ABTO, based on annual projection for 2020 9,12 . Regarding donor characteristics, ABTO considers sex, age group, blood group and cause of death. It was observed a significant decrease in the number of donors due to traumatic brain injury (TBI) in 2020, although lower than in 2019 9,12 (Table 5).
There was an increase in the number of active patients on the waiting list for heart and kidney transplantation in 2020 9,12 (Table 6).