Characteristics of mortality and reintensification/salvage therapy in this study. (A) Cause of death for patients with pre-BMT mortality (n = 12). Most patients with pre-BMT mortality had active HLH at time of death. Infection refers to disseminated bacterial and invasive fungal disease. (B) The use of salvage therapy, displayed as percentages, and time to therapy initiation (range, 7-100 days) were not associated with pre-BMT mortality (P > .05). (C) Characteristics of reintensified or alternative therapies for patients who survived or died pre-BMT. Categorical variables were analyzed using Fisher exact t test and continuous variables using the Mann-Whitney U test. Further details of salvage therapies and associated outcomes are shown in supplemental Table 2 and detailed cause of death for patients with pre-BMT mortality in supplemental Table 3. MOF, multiorgan failure; ns, not significant; reintensified etoposide, biweekly etoposide after week 2 of therapy; reintensified dexamethasone, increased dose to 10 mg/m² after week 2 of therapy.