TNFRSF13B and lymphoproliferative syndrome: Patients with a biallelic mutation were older at the time of our study and presented with higher rates of sinusitis (83.3% vs 46.2%, P = 0.002), bronchiectasis (33.3% vs 10.5%, P = 0.006), and lymphoproliferative disorders (72.2% vs 42.6%, P = 0.03) compared with patients with single TNFRSF13B mutations (Table 1).