Pneumatosis cystoides intestinalis developing subsequent to allogeneic hematopoietic stem cell transplantation for mixed phenotype acute leukemia

: We present the case of a 39-year-old man with a primary diagnosis of mixed phenotype acute leukemia, T/myeloid not otherwise specified (T/M-MPAL). After achieving a complete remission (CR), he underwent allogeneic hematopoietic stem cell transplantation (HSCT). Subsequent evaluation of the cerebrospinal fluid suggested central nervous system graft versus host disease (GVHD); hence, prednisolone therapy was initiated. After 118 days on prednisolone, a routine follow-up thoracic and abdominal computed tomography (CT) revealed extensive pneumatosis in the wall of the colon. We diagnosed his condition as pneumatosis cystoides intestinalis (PCI). The patient was treated conservatively with high concentration oxygen. A CT scan performed 1 week later revealed that the pneumatosis had fully resolved; no relapse has been observed. Various etiologies of PCI have been reported previously. However, there are very few reports of PCI presenting in association with hematologic neoplasms or in response to allogeneic HSCT in adult patients.