The risk of traumatic lumbar punctures in children with acute lymphoblastic leukaemia

Menée au Canada auprès de patients pédiatriques atteints d'une leucémie lymphoblastique aiguë, cette étude de cohorte rétrospective analyse les facteurs de risque associés à des ponctions lombaires traumatiques

Résumé en anglais

Traumatic lumbar punctures with blasts (TLP+) in children with acute lymphoblastic leukaemia (ALL) obscure central nervous system status and are associated with a poorer event-free survival (EFS). We conducted a retrospective cohort study of all lumbar punctures (LPs) for children with ALL diagnosed at our institution from 2005 to 2009. We utilised random-effects and fixed-effects repeated-measures logistic regression analyses to identify risk factors for TLPs. Fixed-effects models use each patient as his or her own control. We used survival analysis to describe outcomes after a TLP+. 264 children underwent 5267 evaluable lumbar punctures (LPs), of which 944 (17.9%) were traumatic. In the multivariable random-effects model, variables significantly associated with TLPs were age <1year (odds ratio (OR) 3.46, 95% confidence interval (CI) 2.06–5.81) or age ⩾10years (OR 2.00, CI 1.66–2.40); body mass index percentile ⩾95 (OR 1.44, CI 1.19–1.75); platelet count <100×103/μL (OR 1.49, CI 1.08–20.7); fewer days since previous LP (OR 5.13, CI 2.34–11.25 for ⩾16days versus 0–3days); and a preceding TLP (OR 1.43, CI 1.19–1.73). In the fixed-effects model, image-guidance reduced the odds of TLP (OR 0.55, CI 0.32–0.95). The 5-year EFS (±SE) for children with TLP+ (77±8%) was significantly lower than for children with CNS1 status (93±2%; p=0.002). The frequency of TLP remains high. Consistent with previous studies, a TLP+ at diagnosis was associated with a poorer EFS. These risk factors can allow identifying interventions to reduce TLPs and directing interventions to those at highest risk.