Key words : Living related kidney transplant, Living related liver transplant, Pandemics

Introduction
Solid-organ transplant is the only curative treatment for end-stage renal disease (ESRD) and end-stage liver disease (ESLD). The worldwide prevalence of chronic renal failure in children is 759 per million population. However, the incidence of chronic liver disease in newborn children is 1 in 2700.¹ As a result of advances in surgical techniques and immunosuppressive therapies, the 10-year survival rate in recipients after transplant is now more than 85%.² The low number of available donors and organs, especially in pediatric patients, has impeded efforts to discover the definitive treatment for these patients.

Coronavirus disease 2019 (COVID-19) first appeared December 31, 2019, in Wuhan, China, and soon spread throughout the world.³ The rapid transmission of the disease through respiration and person-to-person contact has required development of strict preventative protocols and procedures among social, economic, and health care fields at a global level. In response to the rapid spread of COVID-19, many centers postponed or canceled all transplant operations to prevent exposure of immunosuppressed patients, who are at higher risk of infection compared with the general population.⁴ However, our studies have not shown a significantly higher risk of COVID-19 infection for organ transplant recipients compared with the general population.⁵ In addition, the problems experienced by patients with chronic liver disease and end-stage renal disease waiting for organ transplant, secondary to their existing diseases, should be considered.

We evaluated the results of pediatric kidney transplants (KT) and pediatric liver transplants (LT) performed at our center during the pandemic period in 2021, with the aim to develop precautionary methods and center-oriented strategies that could facilitate safe and sustainable resumption of transplant activities at centers whose programs were suspended during the pandemic.

Materials and Methods
From November 8, 1988, to December 31, 2021, we performed 701 LT procedures, and 334 of these were pediatric transplants. A pediatric left lobe living donor LT procedure was first performed in March 1990 and in adults in April 1990 at our center. A combined LT-KT procedure from a living related donor in May 1992 was the first procedure of its kind to be performed anywhere in the world.

From January 1, 2021, to December 31, 2021, we performed 21 LT and 114 KT procedures. Of these, 19 LT and 12 KT were pediatric transplants. We did not limit our organ transplant activities to our country. We have performed KT and LT procedures for many patients with ESRD and ESLD who traveled to our center from abroad, including Jordan, Kazakhstan, Bulgaria, Somalia, Kenya, Russia, Uzbekistan, Azerbaijan, Kosovo, Saudi Arabia, the Turkish Republic of Northern Cyprus, and Ukraine. We recorded age, sex, body mass index, comorbidities, etiologies, laboratory values, and clinical outcomes of the recipients. Before admission, we performed a COVID-19 polymerase chain reaction test and a thorax computed tomography scan for all donors and recipients. If a diagnosis of COVID-19 was confirmed, then we postponed the transplant procedure for 4 weeks, Necessary consultations and preparations were conducted for patients not suspected of COVID-19, and we immediately prepared the recipients and donors for the transplant procedure.

Regardless of their geographic origin, our center provides the highest level of treatment for all patients, including appropriate recovery care to ensure proper fitness for travel. Prior to discharge from our center, we performed a second COVID-19 polymerase chain reaction test for all recipients and donors.

Results
We performed a total of 19 pediatric LT procedures in the year 2021, of whom 11 were female and 8 were male, with a mean age of 3.4 years (range, 6 months to 8 years). The most common etiology was biliary atresia (n = 7). Other etiologies were metabolic diseases (n = 4), progressive familial intrahepatic cholestasis (n = 2), Crigler-Najjar syndrome (n = 2), Niemann-Pick disease (n = 1), fulminant hepatitis (n = 1), familial hypercholesterolemia (n = 1), and cryptogenic liver failure (n = 1). All LT grafts were from living related donors who were first-degree (n = 16) or second-degree (n = 3) relatives of the recipients (mother for 11 recipients, father for 5, aunt for 2, and uncle for 1). Mean hospital stay was 17.6 days (range, 6-27 days). Mean total bilirubin level of the recipients was 4.71 mg/dL before surgery and 0.81 mg/dL at 6 months. Mean aspartate aminotransferase level of the recipients was 369.1 U/L before surgery and 47.6 U/L at 6 months. Two LT recipients died from sepsis in the early postoperative period.

We performed 12 pediatric KT procedures in 2021, of whom 8 were female and 4 were male, with a mean age of 14.1 years (range, 9-17 years). The most common etiology was vesicoureteral reflux (n = 5). Other etiologies were focal segmental glomerulosclerosis (n = 2), immunoglobulin A nephropathy (n = 1), nephronophthisis (n = 1), granulomatosis with polyangiitis (previously known as Wegener granulomatosis; n = 1), neurogenic bladder dysfunction (n = 1), and idiopathic nephrotic syndrome (n = 1). One KT graft was from a deceased donor. All other KT grafts were from living related donors who were first-degree relatives of the recipients (n = 11; mother for 8 recipients, father for 3 recipients). Mean hospital stay was 4.3 days (range, 3-9 days). Mean serum creatinine level of the recipients was 3.29 mg/dL before surgery and 1.17 mg/dL at 6 months. All KT patients were discharged successfully.

Discussion
Our results showed that organ transplant procedures can be successfully maintained during a pandemic period.

Solid-organ transplant is the only curative treatment for patients with ESRD and ESLD. In addition, in pediatric patients with acute liver failure complicated by nonmetastatic but unresectable liver malignancy, long-term survival can only be achieved with LT. Until donors are matched to them, patients with ESRD on the KT wait list are likely to experience problems secondary to their existing disease, such as anemia, bone mineral disorders, and hemodynamic disorders.⁶ Similarly, patients with ESLD on the LT wait list are at risk for complications such as portal hypertension, recurrent cholangitis, and malnutrition.⁷

After the declaration of the worldwide COVID-19 pandemic, new international health care regulations were established, including recommendations to suspend all elective medical and surgical procedures as part of a larger effort to redistribute resources and enhance hospitals’ capacity for the imminent surge of patients who would seek treatment for this highly transmissible disease, as well as the additional burden of severe symptoms for some patients.⁸ At many transplant centers where elective surgery had been postponed, solid-organ transplants were also included in their list of suspended procedures. The risk for transplant recipients is an important concern, but risk to donors is an important concern as well. For example, the possibility of COVID-19 infection for a donor who has no disease and would otherwise remain unexposed, and the desire to avoid this scenario, has played an important role in the suspension of solid-organ transplants in many transplant centers.^9,10 Published data have indicated that 68% of LT procedures were delayed in the United States during the pandemic period, and 73% of deceased donor LT procedures could not be performed due to the pandemic. Also, the pandemic prevented 72% of living donor KT procedures and 84% of deceased donor KT procedures during the pandemic period in the United States.¹¹

With the declaration of COVID-19 as a worldwide pandemic, we performed various research studies in our center. Research has previously focused on the effects of the pandemic on ESRD patients and transplant recipients.^3,5 Our research showed that organ transplant recipients were not significantly more affected by the pandemic compared with the general population. Accordingly, we developed protocols for our center and continued our organ transplant activities with new precautions in place. We performed organ transplants not only for pediatric patients from our own country but also for pediatric patients from 12 other countries, including Jordan, Kazakhstan, Bulgaria, Somalia, Kenya, Russia, Uzbekistan, Azerbaijan, Kosovo, Saudi Arabia, the Turkish Republic of Northern Cyprus, and Ukraine. Two LT recipients died from sepsis in the early postoperative period, but all other recipients and their donors were discharged successfully.

Conclusions
Regardless of the disruptions caused by the 2021 pandemic, transplant activities can be performed safely and successfully if appropriate precautions are observed and transplant center-specific strategies are developed to effectively manage the risk of exposure.

References:

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