Anticytokine autoantibodies (AAbs), particularly anti-interferon-gamma (anti-IFN-γ) AAbs, disrupt cytokine functions, leading to infections, autoimmune-like diseases, and conditions resembling interleukin-12 (IL-12)/IFN-γ pathway defects. Advances in genetic testing have clarified overlaps between autoinflammatory, autoimmune disorders, and primary immunodeficiencies but reveal complex phenotypes and pathways. While these insights deepen our understanding of immune mechanisms, they also complicate diagnosis and treatment, with limited options for IFN-γ deficiencies caused by genetic mutations. The adult-onset immunodeficiency with disseminated lymphadenitis due to nontuberculous mycobacteria (NTM) and other opportunistic infections has been linked to high levels of anti-IFN-γ AAbs. This syndrome, initially identified in HIV-negative Asian patients, frequently affects individuals of Asian descent and may be associated with specific human leukocyte antigen (HLA) alleles. The presence of neutralizing anti-IFN-γ AAbs impairs the IFN-γ-dependent immune response, likely contributing to the persistent NTM infection. This study underscores the potential for late-onset anti-IFN-γ AAb syndrome to manifest with disseminated NTM (dNTM) infections, highlights the importance of timely diagnosis and considers rituximab as a potential therapeutic option.

Since extensively-drug resistant (XDR) Salmonella Typhi first emerged in Pakistan in 2016, it has been reported in many countries and has limited treatment options. In Canada, travel-related cases have been documented in Ontario. This case describes the first XDR S. Typhi case in British Columbia, involving a 41-year-old male with recent travel to China and XDR Salmonella Typhi bacteremia. The patient completed 14 days of carbapenem therapy with clinical cure. Whole-genome sequencing data analysis, conducted at British Columbia Centre for Disease Control and National Microbiology Laboratory, confirmed presence of IncY plasmid (matching the plasmid from outbreak in Pakistan) and identification as genotype 4.3.1 (lineage associated with drug-resistant S. Typhi phenotypes). Our isolate’s genotypic resistance profile matched with an XDR case in India. This case highlights that XDR S. Typhi infection acquisition is not limited to travel to South Asia, and pre-travel health assessments and surveillance may be important prevention strategies.