Clinical features at diagnosis of sickle cell disease prior to universal newborn screening in Alberta.

Objectives: Sickle cell disease (SCD) is an inherited multisystem disorder with complications starting in the first year of life. Newborn screening (NBS) can identify infants with SCD and is associated with decreased morbidity and mortality. Variation in availability of NBS in Canada, and lack of standardized screening for immigrant children, may lead to delayed diagnosis. Methods: This was a retrospective cohort study of 126 children aged 0-18 years with SCD registered with the SCD clinic at the Alberta Children's Hospital between January 2003 and January 2018, prior to province-wide universal NBS for SCD. Patient demographic information, circumstances of diagnosis, and other contextual information were collected from patient health records. Descriptive statistics were used to summarize data, with Mood's median test used to compare medians between groups. Results: Forty-three (35%) patients were born in Alberta. Patients were mostly (95.3%) of African descent. Of patients born in Alberta, 63% (26/43) were diagnosed at >12 months of age, with a median age at diagnosis of 18 months (IQR = 4-39). This was significantly older (P < 0.001) than children born in the USA or in Canadian provinces with SCD NBS programs, where the median age at diagnosis was zero months (N = 36). Of the 42% of patients born outside North America, 64% were diagnosed following an acute complication. Conclusions: This study highlights the importance of NBS for early detection and management of SCD, and the importance of screening at-risk immigrants who may not have received NBS for SCD.