Severe acute respiratory syndrome coronavirus 2 infection in the stem cell transplant recipient − clinical spectrum and outcome

Abstract

Purpose of reviewFocusing on large multicenter cohorts reported over the last months, this review aims at summarizing the available evidence by July 2021 on the impact of coronavirus disease 2019 (COVID-19) on hematopoietic stem cell transplant (HSCT) recipients in terms of epidemiology, clinical features, and outcome. Recent findingsThe incidence of COVID-19 in institutional cohorts varied according to different regions and study periods from 0.4% to 8.3%. Clinical presentation was overall comparable to other immunocompromised hosts and the general population. Microbiologically confirmed superinfection occurred in 13-25% of recipients, with most episodes due to hospital-acquired bacteria and few reported cases of COVID-19-associated aspergillosis. Prolonged nasopharyngeal severe acute respiratory syndrome coronavirus 2 shedding has been demonstrated for as long as 210 days. Mortality rates were similar across studies (14.8-28.4%) and did not markedly differ from those observed in nontransplant hematological patients during the first wave. Older age and shorter time from transplantation were associated with mortality, as well as underlying disease status and amount of immunosuppression. No outcome differences were found in most studies between allogeneic and autologous procedures. SummaryConsiderable advances have been achieved in the characterization of COVID-19 in the HSCT population, although uncertainties remain in the optimal therapeutic management.

COVID-19 and HSCT (Hematopoietic stem cell transplant)

“…Prolonged SARS-CoV-2 shedding is well described in the HSCT population [ 20 , 21 ]. Chemotherapeutic agents employed in the treatment of malignancy in the time leading up to transplant and in the conditioning regimen along with immunosuppressive medications for prevention and treatment of GVHD contribute to the immune suppressed state that allow for prolonged shedding.…”

“…ǂ variable definition of severe disease, *variable follow-up time. Author, site(s) Diagnosis period # HSCT recipients: auto/allo/CAR-T Age, years – median (range) Time since HSCT or CAR-T – median (range) % asymptomatic % hospitalized % required supplemental O2 % required ICU care % require mechanical ventilation % severe COVID ǂ % COVID-specific mortality* % overall mortality* % mortality (by time from diagnosis) Altuntas, Republic of Turkey (Ministry of Health database) 3/11/20–5/29/20 32: 20/12/0 56.5 [ [17] , [18] , [19] ] 100 22 16 22 16 Coll, Spain (national)*not all lab confirmed on or before 7/13/20 113: 42/71/0 Auto:60 [ [55] , [56] , [57] , [58] , [59] , [60] , [61] , [62] , [63] , [64] ] 18 months [ [4] , [5] , [6] , [7] , [8] , [9] , [10] , [11] , [12] , [13] , [14] , [15] , [16] , [17] , [18] , [19] , [20] , [21] ...…”

Viral cultures, cycle threshold values and viral load estimation for assessing SARS-CoV-2 infectiousness in haematopoietic stem cell and solid organ transplant patients: a systematic review

“…[ 2 ] However, identification of respiratory viral shedding, by reverse transcriptase polymerase chain reaction (RT-PCR), depending on the testing platform does not necessarily correlate with the presence of replication-competent virus. [ 3 ] Accordingly, we sought to perform a systematic review of RT-PCR testing and viral culture of SARS-CoV-2, focussing on people receiving solid organ or haematopoietic stem cell transplants, following our published protocol. [ 4 ].…”

SARS-CoV-2 Immunity in Hematopoietic Stem Cell Transplant and Cell Therapy Recipients: What Do We Know, and What Remains to Be Determined?

“…Although a specific T cell response could be generated in most patients, it would not develop in all HSCT recipients. In the HSCT population, prolonged SARS-CoV-2 shedding has been well documented [6,48]. The primary factors contributing to prolonged viral shedding are closely associated with compromised B or T cell function, resulting from chemotherapeutic agents used before transplantation or the conditioning regimen, in addition to immunosuppressive medications prescribed to prevent or treat graft-vs-host disease (GvHD).…”