Patients with ZAP-70 deficiency often present a history of recurrent opportunistic infections, with autoimmunity, or immune dysregulation such as ulcerative colitis and cytopenia, pustular skin lesions, subcutaneous nodules, lymphoma, Omenn syndrome, and hemophagocytic lymphohistiocytosis (HLH). Here, ZAP70 is linked to hyperinsulinemic hypoglycemia, familial, 4.