TNFRSF13B and Opportunistic infection: Interestingly, the clinical phenotype of these B-negative CVID patients was closer to that of GS cases, both being associated with a higher rate of opportunistic infections in comparison with other PAD cases (17, 38, 53), although CVID B-negative patients display a greater frequency of splenomegaly than that observed in GS cases in the absence of thymoma.