Fatal acute respiratory distress syndrome with diffuse alveolar damage: donor lymphocyte infusion imputability?

Rhinovirus/enterovirus identification by electron microscopy in lower respiratory tract infection in a patient with relapsed myelodysplastic syndrome after allogeneic hematopoietic cell transplantation and donor lymphocyte infusion

Donor lymphocyte infusion (DLI) is a curable treatment option, inducing a graft-versus-tumor effect in patients with relapsed hematological malignancies after allogeneic hematopoietic cell transplantation (allo-HCT). However, not only graft-versus-host disease but also pulmonary complications are problematic adverse events after DLI. Although viral infections can be associated with pulmonary complications after DLI, the mechanism underlying these complications remains unclear. Detecting the causative virus infections after pulmonary complications following DLI is challenging, as invasive examinations, such as bronchoalveolar lavage and lung biopsies, are necessary. Family Picornaviridae, including Human-Rhinovirus (HRV) and Enterovirus (EnV), can induce fatal lower respiratory tract infection (LRTI) in recipients who undergo allo-HCT, which can be underdiagnosed. We encountered a 62-year-old man with relapsed myelodysplastic syndrome 20 days after a second HLA-haplo-identical allo-HCT and 4 DLI procedures who was later found to have HRV and EnV LRTI by postmortem electron microscopy. Despite high-dose immunosuppression, severe hypoxemia did not improve, and he succumbed to respiratory failure. Immunosuppressive therapy for idiopathic pneumonia syndrome after allo-HCT may be effective, but its efficacy for acute respiratory failure after DLI is controversial. Our case indicated that the control of viral replication should be prioritized over that of inflammation in HRV and EnV LRTI after DLI.

Clinical features of non-infectious pulmonary complications after donor lymphocyte infusion in post-transplant patients: The Nagasaki Transplant Group Experience

Donor lymphocyte infusion (DLI) is a therapeutic modality for relapsed hematological malignancies after allogeneic hematopoietic stem cell transplantation. We retrospectively analyzed non-infectious pulmonary complications (non-IPCs) following DLI therapy in 41 post-transplant patients with hematological malignancies, and found that 7 developed post-DLI non-IPCs. The 6-year cumulative incidence of non-IPCs was 18.0%. In these patients, non-IPCs were classified into three subtypes: acute respiratory distress syndrome (ARDS), nonspecific interstitial pneumonia (NSIP), and bronchiolitis obliterans syndrome (BOS). The median intervals from the last date of DLI to the development of ARDS and BOS were 12 days (range, 12-14) and 9.4 months (range, 2.6-61.8), respectively; the intervals between DLI and the development of NSIP were 3.5 and 24.7 in 2 patients. Regarding the status of GVHD before the diagnosis with ARDS, 2 out of 3 patients showed the progression of acute GVHD following DLI therapy. One out of 2 patients with NSIP and all 3 patients with BO had chronic GVHD symptoms prior to the development of non-IPCs. In our cohort, 1 patient died of the progression of NSIP. In conclusion, the present study showed the clinical features of non-IPCs following DLI, suggesting the importance of careful follow-ups for non-IPCs in post-DLI patients.