Kids in America: Newborn Screening for Cystic Fibrosis

Detection of disease-causing CFTR variants in state newborn screening programs

BACKGROUND

Newborn screening (NBS) algorithms for cystic fibrosis (CF) vary in the United State of America and include different cystic fibrosis transmembrane conductance regulator (CFTR) variants. CFTR variant distribution varies among racial and ethnic groups.

OBJECTIVE

Our objectives were to identify differences in detection rate by race and ethnicity for CFTR variant panels, identify each US state detection rate for CFTR variant panels, and describe the rate of false-negative NBS and delayed diagnoses by race and ethnicity.

METHODS

This is a cross-sectional analysis of the detection rate of at least 1 CFTR variant for seven panels by race and ethnicity in genotyped people with CF (PwCF) or CFTR-related metabolic syndrome (CRMS)/CFTR-related disorders in CF Foundation Patient Registry (CFFPR) in 2020. We estimated the case detection rate of CFTR variant panels by applying the detection rate to Census data. Using data from CFFPR, we compared the rate of delayed diagnosis or false-negative NBS by race and ethnicity.

RESULTS

For all panels, detection of at least 1 CFTR variant was highest in non-Hispanic White PwCF (87.5%-97.0%), and lowest in Black, Asian, and Hispanic PwCF (41.9%-93.1%). Detection of at least 1 CFTR variant was lowest in Black and Asian people with CRMS/CFTR-related disorders (48.4%-64.8%). States with increased racial and ethnic diversity have lower detection rates for all panels. Overall, 3.8% PwCF had a false-negative NBS and 11.8% had a delayed diagnosis; Black, Hispanic, and mixed-race PwCF were overrepresented.

CONCLUSION

CFTR variant panels have lower detection rates in minoritized racial and ethnic groups leading to false-negative NBS, delayed diagnosis, and likely health disparities.

Contemporary topics in pediatric pulmonology for the primary care clinician

Disorders of the respiratory system are commonly encountered in the primary care setting. The presentations are myriad and this review will discuss some of the more intriguing or vexing disorders that the clinician must evaluate and treat. Among these are dyspnea, chronic cough, chest pain, wheezing, and asthma. Dyspnea and chest pain have a spectrum ranging from benign to serious, and the ability to effectively form a differential diagnosis is critical for reassurance and treatment, along with decisions on when to refer for specialist evaluation. Chronic cough is one of the more common reasons for primary care office visits, and once again, a proper differential diagnosis is necessary to assist the clinician in formulating an appropriate treatment plan. Infant wheezing creates much anxiety for parents and accounts for a large number of office visits and hospital admissions. Common diagnoses and evaluation strategies of early childhood wheezing are reviewed. Asthma is one of the most common chronic diseases of children and adults. The epidemiology, diagnosis, evaluation, treatment, and the patient/parent education process will be reviewed. A relatively new topic for primary care clinicians is cystic fibrosis newborn screening. The rationale, methods, outcomes, and implications will be reviewed. This screening program may present some challenges for clinicians caring for newborns, and an understanding of the screening process will help the clinician communicate effectively with parents of the patient.