Different penetrance of disseminated infections caused by nontuberculous Mycobacteria in Mendelian susceptibility to mycobacterial disease associated with a novel mutation.

Deficiency in the interleukin12/INFgamma pathway is a genetic condition that predisposes to some infections, including nontuberculous mycobacteria infection and extraintestinal salmonellosis. We report 2 cases in sisters who were diagnosed with a genetic defect caused by a new mutation in Interleukin-12 receptor β1 chain (IL12Rβ1) leading to different clinical presentations and responses to therapy.