A case report and review of clinical and laboratory pointers of leukemia in children with bone pain

Abstract

Introduction: About 20-30% of children with acute lymphoblastic leukemia (ALL) present with bone pain, mainly in the lower extremities that can lead to limping or refusal to walk. These children suffer almost exclusively from B-precursor ALL and often present with a nearly normal complete blood count with few or no circulating lymphoblasts. Moreover, they are frequently misdiagnosed as suffering from juvenile arthritis. Case Report: We present case of a 5-year-old boy with mild skeletal complaints for one month who was diagnosed with ALL despite a normal physical examination and minimally affected complete blood count (mild anemia and lymphocytosis alone, with a normal platelet count). Conclusion: Children with ALL and musculoskeletal complaints may have a deceptively normal physical examination at presentation, absence of circulating blasts, and few if any abnormalities on the initial hemogram. Clinical and laboratory pointers to leukemia include bone tenderness or pain, especially if nocturnal and non-articular, anemia of any degree, low-normal leukocytes with relative lymphocytosis, red cell macrocytosis, low-normal platelet counts, especially when associated with elevated erythrocyte sedimentation rate and increased serum LDH. Extreme care is needed in the clinical and laboratory evaluation of children with leukemia and skeletal complaints in order not to miss the underlying diagnosis, misdiagnose juvenile arthritis and/or administer corticosteroids. Acute lymphoblastic leukemia (ALL) is the most common paediatric malignancy comprising approximately 35% of all childhood cancers. About 20-30% of children with ALL present with severe bone pain, mainly in the lower extremities, that can lead to limping or refusal to walk. Sometimes, the skeletal complaints are very subtle but persistent. These children suffer almost exclusively from B-precursor ALL and often present with a nearly normal complete blood count with few or no circulating lymphoblasts.