Clinical trial NCT06908616: Prevalence of Ethnic Neutropenia and Duffy Null Phenotype in Neonates
Official title: The Prevalence of Ethnic Neutropenia in Neonates
Study type: OBSERVATIONAL
Overall status: RECRUITING
Conditions: Neutropenia (Low White Blood Cell Count)
Keywords: Neonates
Neutropenia
Duffy null associated count
Lead sponsor: Kaplan Medical Center
Sponsor class: OTHER
First posted: 2025-04-03
Enrollment: 1000
Sex: ALL
Minimum age (years): 1
Maximum age (years): 1
Standard ages: CHILD
Accepts healthy volunteers: no
Observational model: COHORT
Time perspective: PROSPECTIVE
Sampling method: NON_PROBABILITY_SAMPLE
Study population: Neonates born at Kaplan Medical Center

Brief summary: 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).

Detailed description: 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.

Eligibility criteria: Inclusion Criteria:

* Neonates born at Kaplan Medical Center between 1.9.2024 and 31.12.2025
* Parental informed consent obtained
* Umbilical cord blood available for routine testing

Exclusion Criteria:

* None

Primary outcomes:
measure: Prevalence of Duffy null phenotype in neonates
timeFrame: At birth (umbilical cord sample)
Secondary outcomes:
measure: Prevalence of neutropenia in infants with Duffy null phenotype
timeFrame: 9-12 months
measure: Association between parental ethnicity and Duffy null phenotype
timeFrame: At birth
Other outcomes:
Locations:
city: Rehovot
country: Israel
facility: Kaplan Medical Center
Study officials:
affiliation: Kaplan Medical Center
name: Tal Ben Ami, MD
role: PRINCIPAL_INVESTIGATOR
References:
citation: Gay K, Dulay K, Ravindranath Y, Savasan S. Duffy-Null Phenotype-Associated Neutropenia is the Most Common Etiology for Leukopenia/Neutropenia Referrals to a Tertiary Children's Hospital. J Pediatr. 2023 Nov;262:113608. doi: 10.1016/j.jpeds.2023.113608. Epub 2023 Jul 6.
citation: Rappoport N, Simon AJ, Lev A, Yacobi M, Kaplinsky C, Weingarten M, Somech R, Amariglio N, Rechavi G. Correlation between 'ACKR1/DARC null' polymorphism and benign neutropenia in Yemenite Jews. Br J Haematol. 2015 Sep;170(6):892-5. doi: 10.1111/bjh.13345. Epub 2015 Mar 26. No abstract available.
citation: Atallah-Yunes SA, Ready A, Newburger PE. Benign ethnic neutropenia. Blood Rev. 2019 Sep;37:100586. doi: 10.1016/j.blre.2019.06.003. Epub 2019 Jun 21.