Severe congenital neutropenia due to G6PC3 deficiency: early and delayed phenotype of a patient.

Background: Severe Congenital Neutropenia type 4 (SCN4), is a rare autosomal recessive condition, due to mutations in the G6PC3 gene. The phenotype comprises neutropenia of variable severity and accompanying anomalies.

Case presentation: We report a male patient with confirmed G6PC3 deficiency presented with recurrent bacterial infections and multi-systemic complications. Our case was the first with a novel homozygous frameshift mutation in G6PC3. The patient demonstrated large platelets on his peripheral blood smear which is a rare presentation of this disease.

Conclusion: As SCN4 patients could be easily missed, it is recommended to consider G6PC3 mutation for any case of congenital, unexplained neutropenia.