Effectiveness of preoperative screening for sickle cell disease in a population with a newborn screening program: a cohort study

Abstract

Published clinical practice guidelines recommend that all patients from ethnic groups with a high prevalence of sickle cell disease (SCD) undergo preoperative screening for this hemoglobinopathy. Newborn Screening Ontario initiated a universal sickle hemoglobinopathy screening program in 2006 as part of its regional newborn screening program. The primary objective of this study was to determine the effectiveness of selective preoperative screening for SCD based on at-risk ethnicity in Ontario, a region that has a universal newborn sickle hemoglobinopathy screening program. The hematology laboratory database at our hospital was searched to identify all children who underwent preoperative sickle cell screening in the 42-month period starting in November 2006 (when the newborn sickle hemoglobinopathy screening program was introduced) and ending in April 2010. Medical records of all children testing positive on hemoglobin analysis were reviewed to determine perioperative outcomes. Our search strategy identified 710 children who were born after the introduction of newborn screening and who underwent preoperative screening. Thirty-five of these children had abnormal sickle solubility tests - one (0.14%) was a new diagnosis (not identified by newborn screening), one had been diagnosed previously, and 33 (4.65%) were identified as having sickle cell trait. Sixty children had more than one preoperative screening test performed (range, 2-4). Six of the 35 children with abnormal sickle solubility results underwent repeated testing. Preoperative screening based on at-risk ethnicity alone is an ineffective method of identifying additional children with SCD in Ontario, a population with universal newborn sickle hemoglobinopathy screening. In an effort to avoid unnecessary repeat testing, we propose an algorithm to help physicians decide whether to initiate preoperative sickle cell screening for children.