Abstract
Objectives To report the clinical history, imaging and neurophysiology findings of a case of mononeuritis multiplex caused by acute myeloid leukemia (AML) neuroleukaemiosis
Case A 58-year-old male presented with painless and progressive mononeuropathies after completing high dose cytarabine consolidation treatment for AML. Nine days following chemotherapy a right third nerve palsy developed followed by right 5th, right 7th, left 3rd and left radial, ulnar and peroneal neuropathies.
Serial MRI and PET imaging was unremarkable and 2 cerebrospinal fluid (CSF) were normal. Nerve conduction studies demonstrated abnormal right blink responses, a peroneal neuropathy and evidence of conduction block at a non-compressible site within the left ulnar nerve, however nerve ultrasound did not demonstrate any causative lesion.
Differentials considered included opportunistic fungal infections and a paraneoplastic neuropathy. A third CSF sample performed on day 24 demonstrated myeloblasts, consistent with central nervous system leukaemic infiltration. A diagnosis of neuroleukemiosis was made and intrathecal chemotherapy (initial methotrexate [MTX] and cytarabine, followed by alternating MTX/cytarabine twice a week) plus systemic chemotherapy (fludarabine, cytarabine, idarubicin) and granulocyte-colony stimulating factor was commenced resulting in partial resolution of pre-treatment symptoms.
Conclusions Progressive neuropathies in patients with leukemia are rarely reported and can be diagnostically challenging. Mononeuritis multiplex associated with AML may be painless and focused imaging may fail to demonstrate significant abnormalities. A high index of clinical suspicion is required as the differential diagnoses of neuroleukaemiosis is broad including paraneoplastic syndromes, infection and inflammatory conditions. As in this instance multiple CSF examinations maybe required to confirm its diagnosis.
