Autosomal recessive mendelian susceptibility to mycobacterial diseases (MSMD) due to partial IFNgammaR2 deficiency is a genetic variant of MSMD (see this term) characterized by a partial deficiency in IFN-gammaR2, leading to a residual response to IFN-gamma and consequently to recurrent, moderately severe infections with bacillus Calmette-Guérin (BCG) and other environmental mycobacteria (EM).