Looking at immunological findings at diagnosis, as detailed in Table 5 and Figure 3, isolated or combined IgM deficiency, combined deficiency of IgA and IgM, combined IgG, IgA and IgM defect, low anti-PCP antibody response, and low switched memory B cells were associated with a persistent IEI condition. The gene discussed is CD40LG; the disease is hyperinsulinemic hypoglycemia, familial, 4.