Autosomal dominant mutations in the signal recognition particle (SRP) 54 gene were
recently described in patients with severe congenital neutropenia (SCN). SRP54 deficiency
cause a chronic and profound neutropenia with maturation arrest at the promyelocyte
stage, occurring in the first months of life. Nearly all reported patients with SRP54
mutations had neutropenia without a cyclic pattern and showed a poor or no response
to granulocyte colony-stimulating factor (G-CSF) therapy. We report here an 11-year-old
female patient with cyclic neutropenia and recurrent heterozygous p.T117del (c.349_351del)
in-frame deletion mutation in SRP54, who showed remarkable therapeutic response to
G-CSF treatment. The diagnosis of cyclic pattern of neutropenia was established by
acceptable standards. ELANE gene mutation was excluded by using various genetic approaches.
The patient described here also had dolichocolon which has not been described before
in association with SCN.
