ABSTRACT
Mendelian susceptibility to mycobacterial diseases (MSMD)is a rare congenital disorder characterized by susceptibility to poorly virulent mycobacteria,such as Bacille Calmette-Guerin vaccine or non-tuberculous environmental mycobacteria.The interferon-γ'(IFN-γ)/interleukin-12 (IL-12) pathway is central to controlling mycobacterial infections,in which several genes had been identified.IFN-γ secretion is impaired in patients with IL-12p40 and IL-12 receptor β1 deficiency,where the response to IFN-γ is impaired in patients with IFN-γ receptor 1,IFN-γ receptor 2,and signal transducer and activator of transcription 1 deficiencies.Furthermore,germline mutations in the cytochrome b (-245) beta subunit,interferon regulatory factor 8,ubiquitin-like modifier,RORC and TYK2 have been identified as the genes which are responsible for MSMD.These patients do not generally have associated infections,apart from salmonellosis.Now,the pathogenesis,molecular,clinical,laboratory features,treatment and prognosis were described,in order to support the clues for pediatrician's clinical practice.