Prolonged lumbosacral pain as the initial presentation in acute lymphoblastic leukemia in an adult: A case report.

Rationale: The differential diagnosis of conditions manifesting as bone and joint pain is complex. Although many individuals with acute leukemia experience bone pain, lumbosacral pain as an early feature of acute lymphoblastic leukemia (ALL) is rare.

Patient Concerns: Here we report a case of an adult who presented with a 7-month history of persistent lumbosacral pain which had become more severe during the previous month.

Diagnoses: Prior to referral, his full blood count revealed no abnormalities, and a computerized tomography scan revealed mild bone hyperplasia of his lumbar vertebrae, with disc herniations of L3-S1. His blood biochemistry and urinary test results had been normal. After referral to our clinic, tests of the morphology, immunology, cytogenetics, and molecular biology of his bone marrow led to a diagnosis of MLL-AF4 fusion positive B-cell ALL.

Interventions: Prior to his referral, he had been treated with painkillers by local doctors. The painkillers initially provided pain relief, but their effect wore off over time. After diagnosis, he was started on an adult ALL chemotherapy protocol.

Outcomes: His symptoms resolved within a week of starting chemotherapy. At his most recent assessment, 10 months after diagnosis, he was on maintenance chemotherapy and in remission.

Lessons: This case illustrates that prolonged lumbosacral pain may be a symptom of a life-threatening condition, rather than only attributable to chronic inflammation or disk herniations. Therefore, clinicians need to pay attention to subtle differences in the clinical presentation of patients with lumbosacral pain.