Streptococcus gallolyticus ssp. pasteurianus bacteremia during chemotherapy-induced neutropenia in a patient with malignant lymphoma

Background: Streptococcus gallolyticus ssp. pasteurianus is a commensal bacterium of the alimentary tract in humans and animals. This microorganism not only causes sepsis, endocarditis, and meningitis but is also associated with colorectal tumors. We report herein a rare case of S. gallolyticus ssp. pasteurianus bacteremia in a patient with concomitant colon cancer and aggressive malignant lymphoma during the neutropenic period after chemotherapy against lymphoma. Case presentation: A 79-year-old man was found to have an adenoma in the ascending colon, and endoscopic mucosal resection (EMR) was planned to remove the lesion. However, he was diagnosed with diffuse large B-cell lymphoma during the pre-operation examination. The EMR was postponed, and he received rituximab, cyclophosphamide, etoposide, vincristine, and prednisolone (R-CEOP). He had a neutropenic fever with positive blood cultures for S. gallolyticus ssp. pasteurianus during the first course of R-CEOP. He improved as soon as cefepime was administered. Bacteremia did not recur thereafter, and he underwent EMR after completing six cycles of R-CEOP. The histological diagnosis of the colon tumor was well-differentiated adenocarcinoma in adenoma. Streptococcus gallolyticus ssp. pasteurianus was not detected in the culture of the resected tissue. Conclusion: Although there have been few reports of bloodstream infection due to S. gallolyticus ssp. pasteurianus in patients with hematological malignancies undergoing cytotoxic chemotherapy, physicians should investigate the presence of coexisting colorectal tumors when this bacterium is isolated from blood cultures

Reduced-Intensity Allogeneic Stem Cell Transplantation for Co-Emergence of Chemotherapy-Refractory Follicular Lymphoma and Therapy-Related Myelodysplastic Syndrome

A 54-year-old male was diagnosed with follicular lymphoma in September 2003. Despite multiple chemotherapies, including autologous hematopoietic stem cell transplantation (HSCT) with high-dose chemotherapy, the disease eventually relapsed. Additionally, bone marrow analysis revealed the co-emergence of therapy-related myelodysplastic syndrome (t-MDS) in February 2012. In March 2012, we performed related allogeneic HSCT for the treatment of both malignancies. This strategy was successful and the patient has remained free from both malignancies for 23 months. Allogeneic HSCT is a potent curative therapeutic option for both t-MDS and refractory follicular lymphoma