This study investigated the cognitive and psychosocial outcomes in childhood survivors of hemophagocytic lymphohistiocytosis after hematopoietic stem cell transplantation.

Twenty-one children were assessed on standardized measures of cognitive and psychosocial functioning and compared with an unaffected sibling control group (n = 14). Parent and teacher reports were obtained to provide additional information.

The average full-scale intelligence quotient for the patient cohort was 81 (95% CI, 72-90), which was significantly lower than both the population average of 100 (P = .001) and the average for the unaffected sibling control group (99.2, P = .002). Fifty-six percent of school-aged children were receiving additional support at school, with the majority needing high levels of support. These children also experienced significant psychosocial difficulties. Lower socioeconomic status was associated with poorer cognitive outcomes, but age at transplantation, time to transplantation, type of conditioning, and presence of mixed chimerism were not. Ten (48%) of 21 children had evidence of neurologic involvement at diagnosis, but surprisingly, this was not significantly associated with adverse neurologic outcomes, and some children who did not have any apparent neurologic involvement at diagnosis had severe learning difficulties at follow-up.

In summary, childhood survivors of hemophagocytic lymphohistiocytosis are at risk of long-term cognitive and psychosocial difficulties. Prospective and systematic long-term follow-up of these patients is essential for early identification and effective management of these problems.