Language skills in a child with Leber hereditary optic neuropathy following intrathecal chemotherapy for acute lymphoblastic leukemia.

The language skills of a male child with Leber hereditary optic neuropathy (LHON) and coincidentally treated for acute lymphoblastic leukemia (ALL) with intrathecal chemotherapy at the age of 3 years 8 months were comprehensively evaluated twice over a 6-month period approximately 5½ years after diagnosis of ALL. Despite marked chemotherapy-related leukoencephalopathic changes documented on magnetic resonance imaging, the child presented with stable language skills, which were generally average to above-average based on the normative data from a comprehensive language test battery. In light of the coincidental presentation in the child of a diagnosis of LHON, which may lead to serious vision impairment and increased vulnerability to drug neurotoxicity, coupled with a history of central nervous system (CNS)-directed treatment for ALL resulting in progressive white matter pathology, the study highlights the importance of ongoing monitoring of the child's language development throughout his adolescent years.