Background: Idiopathic granulomatous mastitis (IGM) is a challenging exclusion diagnosis for breast lesions, manifested as benign, chronic inflammation of the breast tissue. Although some evidence suggest that IGM cases are not uniformly distributed worldwide, few investigations have specifically addressed this topic. This study aims to examine the distribution of IGM cases among countries and races/ethnicities based on reported cases.Methods: A review of studies with a report of at least one IGM patient published from 2011 to 2020 inclusive was conducted. The search was performed in MEDLINE, and citations were filtered in two stages by title/abstract and full text. Those cases with a positive growth of pathogens, male granulomatous mastitis and review articles were excluded.Results: Among 365 retrieved publications, 218 were finally included based on the inclusion and exclusion criteria, comprising 7161 patients from 34 different countries. Turkey, the United States, and China were the countries where the most publications (including case reports) originated. Considering the number of patients within papers, Turkey, Iran, and China were the pioneers. Conclusion: Based on the published literature, some populations seem to be more prone to IGM. Further investigations may reveal the genetic and environmental factors associated with this disease in different geographic areas.

Immunocompromised outpatients, including people living with HIV/AIDS (PLWH), diabetes, cancer, and organ transplant recipients, are at high risk of antimicrobial resistance (AMR) due to their weakened immune systems and use of immunosuppressive therapies. The high prevalence of prophylactic and therapeutic antibiotic use in this vulnerable population, coupled with frequent contact with healthcare facilities and limited outpatient antimicrobial resistance surveillance systems, contributes to the increase in antimicrobial resistance. The majority of available data pertains to inpatients, and there is a lack of comprehensive outpatient information on pathogen distribution, resistance patterns, and diagnostic challenges. Moreover, nonspecific clinical presentations, diminished inflammatory responses, and limitations of traditional diagnostic methods complicate infection diagnosis in this population. Increasing resistance surveillance, developing rapid diagnostic tools, and implementing accurate and personalized approaches are key strategies to reduce the burden of disease, mortality, and healthcare costs in the immunocompromised outpatient population. This study was designed as a narrative review based on a comprehensive search of major databases and guidelines. It aims to examine the available evidence and address the challenges associated with AMR in immunocompromised outpatients.