Screening of turner syndrome with novel auxological criteria facilitates early diagnosis

Abstract

Context: Screening criteria for abnormal growth in children are traditionally based on height-for-age, height distance from target height (TH), and change in growth rate. However, there is no consensus on the optimal screening limits.

Objective: Our objective was to first develop new population-based and age-specific cutoffs for these three screening parameters and, second, to validate their performance in screening by using Turner syndrome (TS) as a model.

Design, patients, and main outcome measure: Reference values for the height distance from TH and growth rate were defined in a total of 14,189 healthy girls aged 0-18 yr with 147,469 height measurements. The best formula for TH calculation was TH sd score = 0.79 × mid-parental height sd score - 0.15. We also calculated age-specific limits for the distance from TH and limits for growth rate that were freely scalable between age range 0-12 yr. Longitudinal growth data of a cohort including 124 TS girls were evaluated with receiver operating characteristic analysis against the reference population.

Results: The screening accuracy for TS was excellent when we combined all three screening parameters. Sensitivity was 97% and specificity 96% for all TS girls and 100% and 95% for 45,XO TS girls, respectively. The detection rate was 68% for all and 76% for 45,XO TS girls with 99% specificity by the age of 2 yr.

Conclusion: These new population-based screening rules for TS are sensitive and specific, but their use is complex, and therefore their efficient use requires computerization.