An observational study in Neutropenia (Low White Blood Cell Count), sponsored by Kaplan Medical Center. Recruiting at 1 site in Israel. Open to participants aged 1 Minute to 1 Day. Per ClinicalTrials.gov, last updated 2025-04-06.
Sponsored by Kaplan Medical Center · Observational
This is a prospective observational study designed to assess the prevalence of the Duffy null phenotype (associated with ethnic neutropenia) in neonates born at Kaplan Medical Center. Blood samples will be collected from umbilical cords (non-invasively) to evaluate Duffy antigen expression. Data on ethnicity, perinatal factors, and routine blood counts at 9-12 months (when available) will also be collected to correlate phenotype with absolute neutrophil count (ANC).
This is a prospective, observational cohort study designed to evaluate the prevalence of the Duffy null phenotype (Fya-/Fyb-) and its association with ethnic neutropenia in neonates born at Kaplan Medical Center in Israel. The Duffy null phenotype has been linked to lower peripheral neutrophil counts without increased infection risk in certain ethnic groups, a condition commonly referred to as benign ethnic neutropenia.
Cord blood samples will be collected from approximately 1,000 neonates during routine G6PD testing. An additional 3 mL will be obtained non-invasively from the umbilical cord after labour to determine the expression of Duffy antigens using serologic gel testing. Parental consent will be obtained, and information regarding ethnicity and family history of neutropenia will be collected.
Participants identified with the Duffy null phenotype will be followed through electronic health records to assess their neutrophil counts during routine blood screening at 9-12 months of age. The study will analyze associations between Duffy phenotype, neutropenia prevalence, and parental ethnic origin.
Findings may support improved diagnostic clarity around neonatal neutropenia and help reduce unnecessary interventions in otherwise healthy infants with genetically determined low neutrophil counts.
316 studies on the registry are indexed under Neutropenia; 42 are open to participants now.
This study's planned enrollment of 1,000 is above the median of 203 across 59 observational studies indexed under Neutropenia.
Browse Neutropenia studies →Kaplan Medical Center is the lead sponsor of 37 studies on the registry; 3 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Neonates born at Kaplan Medical Center
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You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Neonates born at Kaplan Medical Center whose cord blood is tested for Duffy antigen status and complete blood count. Follow-up neutrophil data is collected at 9-12 months if available.
Diagnostic Test: Cord blood
Cord blood samples will be collected during routine G6PD testing. An additional 3 mL will be obtained non-invasively from the umbilical cord to determine the expression of Duffy antigens using serologic gel testing.
Prevalence of Duffy null phenotype in neonates
Percentage of neonates born with the Duffy null phenotype (Fya-/Fyb-) as determined by serologic gel-based testing.
Time frame: At birth (umbilical cord sample)
Prevalence of neutropenia in infants with Duffy null phenotype
Percentage of Duffy null infants with ANC \<1000/µL based on routine CBC performed at at 9-12 months
Time frame: 9-12 months
Association between parental ethnicity and Duffy null phenotype
Distribution of Duffy null phenotype stratified by self-reported parental origin.
Time frame: At birth
Plan to share: No — The study involves neonates and is based on anonymized samples; individual-level data will not be shared due to privacy and ethical considerations.
Started Oct 2024 (actual). Primary completion is estimated for Dec 2026, 26 months after the start.
Of 23 observational studies under Neutropenia, half reached primary completion within 43 months of starting (the median), counting those still running; a quarter within 18 and three quarters within 190. This study's planned 26 months is below that.
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