CSF3 and coinfection: Finally, she was diagnosed with SDS and she was treated with compound glycyrrhizin, granulocyte-colony stimulating factor, and antibiotic in the case of co-infection.<h4>Outcomes</h4>During the follow-up, her liver function showed the level of transaminases decreased and she rarely had infection after the age of 15 months although neutropenia is still present.<h4>Lessons</h4>Patients with SDS lacks typical clinical symptoms, which presents a huge challenge for clinicians.