IL-12Rβ1 deficiency is an autosomal recessive disorder characterized bypredisposition to poorly pathogenic mycobacteria, salmonella and candidaspecies. We aimed to analyze the clinical manifestations, immunologicaland genetic features of IL-12Rβ1 deficiency in 10 Turkish patients froma single center. We retrospectively studied the clinical manifestations andgenetic analysis of the IL-12Rβ1 deficiency patients from 2008 to 2016. Tenpatients were diagnosed and followed for eight years. The mean age at onsetand diagnosis were 24.1±42.5 (med:10.5) and 52.3±6.83 (med:20) months,respectively. Parental consanguinity rate was 81.8%. All patients were BCGvaccinated. Abscess and axillary lymphadenopathy in the vaccinated area was themost common initial presentation following the BCG vaccination, six patientshad recurring oral candidiasis. Active infections were treated appropriately, inaddition to prophylactic therapy with IFNɣ. We identified 6 different mutationsin the IL12RB1 gene in 10 patients including 5 splice-site mutations, 3missense, 1 frameshift, 1 premature stop codon. One of these mutations wasnovel. The most common mutation was IVS8+1G>A(c.783+1G>A) followedby p.R175W(c.523C>T). This study emphasizes that patients presented withabscess and axillary lymphadenopathy associated with BCG vaccination shouldbe evaluated for IL-12Rβ1 deficiency.