Human herpesvirus 6B (HHV-6B) encephalitis is a significant cause of central nervous complications after allogeneic stem cell transplantation. When a transplant patient shows central nervous system symptoms, the conditions to suggest HHV-6 B encephalitis include a cord blood transplant, HLA-mismatched unrelated transplant, onset at 2-6 weeks after transplantation, symptoms such as memory impairment or dysesthesia, immune reactions, onset under steroid use, and hyponatremia. For such patients, empiric antiviral therapy is recommended. Full dose foscarnet is recommended as the primary treatment when possible. There is no high quality evidence to recommended strategies for cases in which clinical symptoms do not improve well. We recommend an individualized approach that considers the progression and severity of illness as well as patient comorbidities. General strategies for salvage therapy include extending the treatment period, switching to foscarnet or combination therapy for patients treated with ganciclovir, and combination therapy with ganciclovir for patients treated with foscarnet. Combination therapy with foscarnet and ganciclovir may be considered for patients whose consciousness loss or seizures do not improve well.

 Purpose: To investigate the informative aspects of eating rate in hematopoietic stem cell transplantation (HSCT) using the patients’ nutritional pathway. Methods: Patients who underwent HSCT and followed the patients’ nutritional pathway in the Division of Stem Cell Transplantation at Shizuoka Cancer Center between Jane 2019 and Dec 2019 were evaluated from pre-treatment to the end of parenteral nutrition (PN). Eating rate, caloric intake (kcal/ideal body weight [IBW] kg/day), the PN period, and the relationships between nutrition-related adverse events over time and between eating rate and caloric intake were investigated. Results: Median age of the 10 cases (3 women) was 56 years (range, 32-70 years) and median body mass index was 22.1 kg/m² (18.2-25.8 kg/m²). Median eating rate during the period was 61.3% (34.0-90.9%), caloric intake was 11 kcal/IBW kg/day (7-22 kcal/IBW kg/day), and the PN period was 33 days (15-60 days). Eating rate was correlated with caloric intake and the PN period. (r=0.75, P=0.012; r=−0.65, P=0.044). Nutritional-related adverse events over time, eating rate, and caloric intake showed negative correlations (eating rate: r=−0.57, P<0.001; caloric intake: r=−0.62, P<0.001). Conclusion: Eating rate in allogeneic HSCT using the patients’ nutritional pathway can be informative, and thus beneficial for treatment.