Childhood acute lymphoblastic leukemia presenting with osteoarticular syndrome--characteristics and prognosis.

Children with leukemia often present with osteoarticular syndrome as a first complaint thus mimicking juvenile idiopathic arthritis. The objective of the present study was to determine the frequency of osteoarticular syndrome at the onset of acute lymphoblastic leukemia in childhood, the clinical and laboratory specificity of such patients and the prognostic value of osteoarticular syndrome as an initial symptom.We studied 60 children with acute lymphoblastic leukemia at a mean age of 5 +/- 0.5 years between February 2002 and October 2007.Osteoarticular syndrome was present as an initial symptom of leukemia in 18 (30.5%) patients. The oligoarticular involvement was prevalent--in 8 children (44%). Middle-sized joints were affected more commonly--in 10 patients (55.6%), followed by large joints and spine. Laboratory results in patients with osteoarticular syndrome show more often normal or slightly decreased platelet count, higher values of lactate dehydrogenase and rarely--leukocytosis (> 20 x 10(9)/l). Parablasts in the blood film were detected in 13 children (72.2%) with osteoarticular syndrome. Event-free survival in patients with osteoarticular syndrome is comparable to that of the remaining group of acute lymphoblastic leukemia patients. In conclusion we point out that there should be frequent blood tests in children with osteoarticular syndrome and timely bone marrow biopsy in cases with atypical signs of juvenile arthritis.