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KEY POINTS
The complications of hematopoietic stem cell transplantation can impact any organ system and generally relate to the consequences of the cytoreductive therapy, infections, and in the case of allogeneic transplants, immunosuppression, and development of graft-versus-host disease (GVHD).
GVHD remains one of the most important complications of allogeneic transplantation.
Stem cell transplant recipients may require admission to the intensive care unit (ICU) for close monitoring for volume and electrolyte issues, vasopressor or renal support, and mechanical ventilation.
The approach to the diagnosis and management of infectious disorders in the stem cell transplant recipient is dependent on the underlying disease and prior therapy, timing of the infection relative to the transplant, the type of transplant, and the patient’s immunologic history and comorbidities.
Pulmonary complications develop in up to 60% of allogeneic transplant recipients and are the immediate cause of death in approximately half of the cases.
Major noninfectious pulmonary complications in the early transplant period include idiopathic pneumonia syndrome, diffuse alveolar hemorrhage, and peri-engraftment respiratory distress syndrome; bronchiolitis obliterans syndrome and bronchiolitis obliterans organizing pneumonia occur later.
Despite advances in supportive care in the ICU, the mortality rate of allogeneic transplant recipients who develop respiratory failure and multiple organ failure remains extremely high.
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Hematopoietic stem cell transplantation (HSCT) has become an expanding modality for the treatment of benign and malignant hematologic diseases. Hematopoietic stem cells (HSCs) give rise to mature blood cells, and can be derived from bone marrow, peripheral blood, or umbilical cord blood (UCB).
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A stem cell transplant can be broken down into three components: the graft, the conditioning, and the graft-versus-host disease (GVHD) prophylaxis. With respect to the “graft,” HSCT involves the use of autologous HSC, derived from the patient, or allogeneic HSC, derived from a related or unrelated donor (Fig. 97-1). In 2018, more than 14,000 autologous and 9000 allogeneic HSCTs were performed in the United States.1 High-dose chemotherapy followed by autologous HSCT is a commonly used treatment for patients with multiple myeloma and lymphomas (both Hodgkin’s and non-Hodgkin’s),1 and is also used to treat metastatic germ cell tumors2 and select autoimmune diseases.3
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With autologous HSCT, the patient’s HSCs are mobilized from the bone marrow into peripheral blood and then collected by apheresis (Fig. 97-2). This mobilization is accomplished via a white blood cell (WBC) growth factor (ie, granulocyte-colony stimulating factor [G-CSF]) and/or stem cell mobilizer (ie, plerixafor), or by performing apheresis at time of blood count recovery following chemotherapy (a time when there are more HSCs circulating in peripheral blood). In an autologous HSCT, the stem cells are only used to rescue the bone marrow from the damage caused by the myeloablative therapy given just prior to the stem cell infusion to treat ...