A 4 y/o patient presents with recurrent sinus infections. The boy has a history of infections with pyogenic (pus-forming) bacteria. IgM levels were measured to be about 220 mg/dL (normal: 75-150 mg/dL). Patient has normal T cell and B cell levels. Below, a flow diagram is presented from the patient, showing bound soluble CD40.
Based on this flow diagram, what would you suspect the patient has?