Congenital Neutropenia Patient With Hypomorphic Biallelic CSF3R Mutation Responding to GCSF

Area of Science:

• Hematology
• Genetics
• Immunology

Background:

• Congenital neutropenia (CN) is a rare group of disorders characterized by low neutrophil counts.
• Mutations in ELANE, HAX1, G6PC3, and JAGN1 are common causes of CN, often responsive to Granulocyte Colony Stimulating Factor (GCSF).
• Biallelic mutations in the Colony Stimulating Factor 3 Receptor (CSF3R) gene have been identified in some CN patients, typically non-responsive to GCSF.

Observation:

• This report details a case of congenital neutropenia in a patient with a hypomorphic biallelic CSF3R mutation.
• Previous literature suggests CSF3R mutations confer GCSF unresponsiveness.

Findings:

• The presented patient with a hypomorphic biallelic CSF3R mutation demonstrated a positive clinical response to GCSF treatment.
• This finding contrasts with the established understanding of GCSF unresponsiveness in patients with CSF3R mutations.

Implications:

• This case suggests that certain CSF3R mutations may not confer complete GCSF unresponsiveness.
• It highlights the importance of considering GCSF treatment even in patients with identified CSF3R mutations, depending on mutation type.
• Further research is warranted to explore the spectrum of CSF3R mutations and their variable responses to GCSF in congenital neutropenia.