A Rare Case of Aleukemic B‐Cell Acute Lymphoblastic Leukemia Presenting as Rapidly Progressive Severe Low Back Pain in an Adolescent With a History of Anxiety and Depression
TingTing Huang, Lingbin Meng, Linghua Zheng, Xue Han, Ephraim Ansa-Addo, Feng HongIntroduction
Musculoskeletal complaints are a frequent cause of pediatric emergency visits. While adolescent back pain is typically benign, it can occasionally signal underlying malignancy. Distinguishing organic pathology from functional disorders is particularly challenging in patients with pre‐existing psychiatric comorbidities, leading to potential diagnostic delays.
Case Presentation
We report a 17‐year‐old female with a history of anxiety and depression presenting with two weeks of severe lumbar pain and progressive gait difficulty. Initial evaluations, including spinal radiography and complete blood count, were unremarkable. Her symptoms were initially attributed to musculoskeletal strain. However, as symptoms persisted, her psychiatric history may have contributed to diagnostic overshadowing when psychogenic factors were subsequently considered. Rapid functional deterioration prompted further workup, revealing markedly elevated inflammatory markers and lactate dehydrogenase (LDH). Magnetic resonance imaging (MRI) demonstrated diffuse marrow signal abnormalities. Subsequent bone marrow biopsy confirmed B‐cell acute lymphoblastic leukemia (B‐ALL). Cytogenetics analysis showed a normal karyotype.
Discussion
ALL rarely initially presents with isolated back pain in adolescents, commonly resulting in delayed diagnosis. This delay can be further exacerbated by diagnostic overshadowing, a cognitive bias in which a patient’s psychiatric history leads clinicians to prematurely attribute severe somatic symptoms to functional or psychogenic etiologies. This case also highlights that early leukemic bone marrow infiltration may occur despite normal peripheral blood counts and unrevealing plain radiographs. Therefore, persistent symptoms and rapid clinical deterioration despite initially reassuring investigations should prompt reconsideration of the diagnosis and additional evaluation, including selected laboratory studies, such as LDH and inflammatory markers, and advanced imaging (MRI) when clinically indicated.
Conclusion
This case underscores the importance of maintaining a broad differential diagnosis and looking beyond psychiatric comorbidities when evaluating adolescents with persistent or nocturnal back pain accompanied by rapid functional decline, despite initial reassuring radiographs and hematologic studies. In such patients, additional laboratory assessment and MRI may be considered when the clinical course is disproportionate to an expected musculoskeletal injury, helping to identify serious underlying pathology and reduce the risk of diagnostic delay.